Merge branch 'master' into webp-lossless

# Conflicts:
#	tests/webp/.gitignore
#	tests/webp/CMakeLists.txt
#	tests/webp/Makemodule.am

309 files changed, 3858 insertions, 723 deletions

diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index c4fa9ca..b279f63 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -1,4 +1,3 @@
-
 if (BUILD_TEST)
 	SET(DART_TESTING_TIMEOUT 5)
 
@@ -18,6 +17,7 @@ if (BUILD_TEST)
 	include_directories (BEFORE ${GD_INCLUDE_DIR} "${GDTEST_SOURCE_DIR}" "${CMAKE_BINARY_DIR}" "${CMAKE_BINARY_DIR}/tests/gdtest")
 
 	SET(TESTS_DIRS
+		avif
 		bmp
 		fontconfig
 		freetype
@@ -28,16 +28,23 @@ if (BUILD_TEST)
 		gdimageclone
 		gdimagecolor
 		gdimagecolorclosest
+		gdimagecolorclosesthwb
 		gdimagecolordeallocate
 		gdimagecolorexact
+		gdimagecolormatch
 		gdimagecolorreplace
 		gdimagecolorresolve
 		gdimagecolortransparent
+		gdimagecompare
 		gdimagecontrast
 		gdimageconvolution
 		gdimagecopy
+		gdimagecopymerge
+		gdimagecopymergegray
 		gdimagecopyresampled
+		gdimagecopyresized
 		gdimagecopyrotated
+		gdimagecreate
 		gdimagecrop
 		gdimagefile
 		gdimagefill
@@ -48,6 +55,7 @@ if (BUILD_TEST)
 		gdimagefilltoborder
 		gdimagefilter
 		gdimageflip
+		gdimageellipse
 		gdimagegrayscale
 		gdimageline
 		gdimagenegate
@@ -58,16 +66,24 @@ if (BUILD_TEST)
 		gdimagerotate
 		gdimagescale
 		gdimagescatterex
+		gdimagesetinterpolationmethod
 		gdimagesetpixel
+		gdimagesquaretocircle
+		gdimagestring
+		gdimagestring16
 		gdimagestringft
 		gdimagestringftex
+		gdimagestringup
+		gdimagestringup16
 		gdimagetruecolortopalette
 		gdinterpolatedscale
 		gdnewfilectx
 		gdtest
 		gdtiled
 		gdtransformaffineboundingbox
+		gdtransformaffinecopy
 		gif
+		heif
 		jpeg
 		png
 		tga
diff --git a/tests/Makefile.am b/tests/Makefile.am
index fc5ed2b..3630810 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -13,6 +13,7 @@ CLEANFILES =
 EXTRA_DIST =
 TESTS =
 
+include avif/Makemodule.am
 include bmp/Makemodule.am
 include fontconfig/Makemodule.am
 include freetype/Makemodule.am
@@ -23,16 +24,23 @@ include gdimagebrightness/Makemodule.am
 include gdimageclone/Makemodule.am
 include gdimagecolor/Makemodule.am
 include gdimagecolorclosest/Makemodule.am
+include gdimagecolorclosesthwb/Makemodule.am
 include gdimagecolordeallocate/Makemodule.am
 include gdimagecolorexact/Makemodule.am
+include gdimagecolormatch/Makemodule.am
 include gdimagecolorreplace/Makemodule.am
 include gdimagecolorresolve/Makemodule.am
 include gdimagecolortransparent/Makemodule.am
+include gdimagecompare/Makemodule.am
 include gdimagecontrast/Makemodule.am
 include gdimageconvolution/Makemodule.am
 include gdimagecopy/Makemodule.am
+include gdimagecopymerge/Makemodule.am
+include gdimagecopymergegray/Makemodule.am
 include gdimagecopyresampled/Makemodule.am
+include gdimagecopyresized/Makemodule.am
 include gdimagecopyrotated/Makemodule.am
+include gdimagecreate/Makemodule.am
 include gdimagecrop/Makemodule.am
 include gdimagefile/Makemodule.am
 include gdimagefill/Makemodule.am
@@ -43,6 +51,7 @@ include gdimagefilledrectangle/Makemodule.am
 include gdimagefilltoborder/Makemodule.am
 include gdimagefilter/Makemodule.am
 include gdimageflip/Makemodule.am
+include gdimageellipse/Makemodule.am
 include gdimagegrayscale/Makemodule.am
 include gdimageline/Makemodule.am
 include gdimagenegate/Makemodule.am
@@ -53,16 +62,24 @@ include gdimagerectangle/Makemodule.am
 include gdimagerotate/Makemodule.am
 include gdimagescale/Makemodule.am
 include gdimagescatterex/Makemodule.am
+include gdimagesetinterpolationmethod/Makemodule.am
 include gdimagesetpixel/Makemodule.am
+include gdimagesquaretocircle/Makemodule.am
+include gdimagestring/Makemodule.am
+include gdimagestring16/Makemodule.am
 include gdimagestringft/Makemodule.am
 include gdimagestringftex/Makemodule.am
+include gdimagestringup/Makemodule.am
+include gdimagestringup16/Makemodule.am
 include gdimagetruecolortopalette/Makemodule.am
 include gdinterpolatedscale/Makemodule.am
 include gdnewfilectx/Makemodule.am
 include gdtest/Makemodule.am
 include gdtiled/Makemodule.am
 include gdtransformaffineboundingbox/Makemodule.am
+include gdtransformaffinecopy/Makemodule.am
 include gif/Makemodule.am
+include heif/Makemodule.am
 include jpeg/Makemodule.am
 include png/Makemodule.am
 include tga/Makemodule.am
@@ -83,10 +100,12 @@ EXTRA_DIST += \
 
 # We don't keep any media files in the top dir ... just generated outputs.
 CLEANFILES += \
+	*.avif \
 	*.bmp \
 	*.gd \
 	*.gd2 \
 	*.gif \
+	*.heif \
 	*.jpeg \
 	*.jpg \
 	*.png \
diff --git a/tests/avif/.gitignore b/tests/avif/.gitignore
new file mode 100644
index 0000000..66233b0
--- /dev/null
+++ b/tests/avif/.gitignore
@@ -0,0 +1,5 @@
+/avif_im2im
+/avif_null
+/avif_ptr_double_free
+/bad_input
+/compare_avif_to_png
diff --git a/tests/avif/CMakeLists.txt b/tests/avif/CMakeLists.txt
new file mode 100644
index 0000000..e2df47b
--- /dev/null
+++ b/tests/avif/CMakeLists.txt
@@ -0,0 +1,17 @@
+IF(AVIF_FOUND)
+LIST(APPEND TESTS_FILES
+	avif_ptr_double_free
+	avif_im2im
+	avif_null
+	bad_input
+)
+
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	compare_avif_to_png
+)
+ENDIF(PNG_FOUND)
+
+ENDIF(AVIF_FOUND)
+
+ADD_GD_TESTS()
diff --git a/tests/avif/Makemodule.am b/tests/avif/Makemodule.am
new file mode 100644
index 0000000..f7b965a
--- /dev/null
+++ b/tests/avif/Makemodule.am
@@ -0,0 +1,24 @@
+if HAVE_LIBAVIF
+libgd_test_programs += \
+	avif/avif_ptr_double_free
+	avif/avif_im2im
+	avif/avif_null
+	avif/bad_input
+
+if HAVE_LIBPNG
+libgd_test_programs += \
+	avif/compare_avif_to_png
+endif
+
+endif
+
+EXTRA_DIST += \
+	avif/CMakeLists.txt \
+	avif/baboon.avif \
+	avif/baboon.png \
+	avif/dice_with_alpha.avif \
+	avif/dice_with_alpha.png \
+	avif/plum_blossom_12bit.avif \
+	avif/plum_blossom_12bit.png \
+	avif/sunset.avif \
+	avif/sunset.png
diff --git a/tests/avif/avif_im2im.c b/tests/avif/avif_im2im.c
new file mode 100644
index 0000000..3a07ebd
--- /dev/null
+++ b/tests/avif/avif_im2im.c
@@ -0,0 +1,67 @@
+/**
+ * File: avif_im2im
+ *
+ * Sanity check for AVIF encoding and decoding.
+ * We create a simple gd image, we encode it to AVIF, and we decode it back to gd.
+ * Then we make sure the image we started with and the image we finish with are the same.
+ *
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+#include <stdio.h>
+
+int main()
+{
+	gdImagePtr srcGdIm, destGdIm;
+	void *avifImageDataPtr;
+	FILE *fp;
+	int r, g, b;
+	int size = 0;
+	CuTestImageResult result = {0, 0};
+
+	// Create new gd image and add some shapes to it.
+	srcGdIm = gdImageCreateTrueColor(100, 100);
+	gdTestAssertMsg(srcGdIm != NULL, "could not create source image\n");
+
+	r = gdImageColorAllocate(srcGdIm, 0xFF, 0, 0);
+	g = gdImageColorAllocate(srcGdIm, 0, 0xFF, 0);
+	b = gdImageColorAllocate(srcGdIm, 0, 0, 0xFF);
+	gdImageFilledRectangle(srcGdIm, 0, 0, 99, 99, r);
+	gdImageRectangle(srcGdIm, 20, 20, 79, 79, g);
+	gdImageEllipse(srcGdIm, 70, 25, 30, 20, b);
+
+	// Encode the gd image to a test AVIF file.
+	fp = gdTestTempFp();
+	gdImageAvif(srcGdIm, fp);
+	fclose(fp);
+
+	// Encode the gd image to an AVIF image in memory.
+	avifImageDataPtr = gdImageAvifPtrEx(srcGdIm, &size, 100, 10);
+	gdTestAssertMsg(avifImageDataPtr != NULL, "gdImageAvifPtr() returned null\n");
+	gdTestAssertMsg(size > 0, "gdImageAvifPtr() returned a non-positive size\n");
+
+	// Encode the AVIF image back into a gd image.
+	destGdIm = gdImageCreateFromAvifPtr(size, avifImageDataPtr);
+	gdTestAssertMsg(destGdIm != NULL, "gdImageAvifPtr() returned null\n");
+
+	// Encode that gd image to a test AVIF file.
+	fp = gdTestTempFp();
+	gdImageAvif(destGdIm, fp);
+	fclose(fp);
+
+	// Make sure the image we started with is the same as the image after two conversions.
+	 gdTestImageDiff(srcGdIm, destGdIm, NULL, &result);
+	 gdTestAssertMsg(result.pixels_changed == 0, "pixels changed: %d\n", result.pixels_changed);
+
+	if (srcGdIm)
+		gdImageDestroy(srcGdIm);
+
+	if (destGdIm)
+		gdImageDestroy(destGdIm);
+
+	if (avifImageDataPtr)
+		gdFree(avifImageDataPtr);
+
+	return gdNumFailures();
+}
diff --git a/tests/avif/avif_null.c b/tests/avif/avif_null.c
new file mode 100644
index 0000000..bbcc9c6
--- /dev/null
+++ b/tests/avif/avif_null.c
@@ -0,0 +1,23 @@
+/**
+ * File: avif_null.c
+ *
+ * Simple test case, confirming that if you try to create an AVIF image from a
+ * null file pointer, the creation will fail, and it will return NULL.
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+	gdImagePtr im;
+
+	im = gdImageCreateFromAvif(NULL);
+	if (!gdTestAssert(im == NULL))
+		gdImageDestroy(im);
+
+	gdImageAvif(im, NULL); /* noop safely */
+
+	return gdNumFailures();
+}
diff --git a/tests/avif/avif_ptr_double_free.c b/tests/avif/avif_ptr_double_free.c
new file mode 100644
index 0000000..8160950
--- /dev/null
+++ b/tests/avif/avif_ptr_double_free.c
@@ -0,0 +1,34 @@
+/**
+ * Test that failure to convert to AVIF returns NULL
+ *
+ * We are creating an image, set its width to zero, and pass this image to
+ * gdImageAvifPtr().
+ * This is supposed to fail, and as such should return NULL.
+ *
+ * See also <https://github.com/libgd/libgd/issues/381>
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr src, dst;
+	int size;
+
+	src = gdImageCreateTrueColor(1, 10);
+	gdTestAssert(src != NULL);
+
+	src->sx = 0;  // making the width 0 should cause gdImageAvifPtr() to fail
+
+	dst = gdImageAvifPtr(src, &size);
+	gdTestAssert(dst == NULL);
+
+	if (src)
+		gdImageDestroy(src);
+
+	if (dst)
+		gdImageDestroy(dst);
+
+	return gdNumFailures();
+}
diff --git a/tests/avif/baboon.avif b/tests/avif/baboon.avif
new file mode 100644
index 0000000..f5821db
--- /dev/null
+++ b/tests/avif/baboon.avif
diff --git a/tests/avif/baboon.png b/tests/avif/baboon.png
new file mode 100644
index 0000000..fdc5dcb
--- /dev/null
+++ b/tests/avif/baboon.png
diff --git a/tests/avif/bad_input.c b/tests/avif/bad_input.c
new file mode 100644
index 0000000..0f814c9
--- /dev/null
+++ b/tests/avif/bad_input.c
@@ -0,0 +1,57 @@
+/**
+ * File: bad_input.c
+ *
+ * Make sure that the AVIF encoding and decoding functions handle bad input gracefully.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include "gd.h"
+#include "gdtest.h"
+
+int main() {
+	FILE *fp;
+	int retval;
+	gdImagePtr realIm, badIm;
+	void *rv;
+	int size;
+
+	// Read in an AVIF image for testing.
+
+	fp = gdTestFileOpen2("avif", "sunset.avif");
+	realIm = gdImageCreateFromAvif(fp);
+	fclose(fp);
+	if (!gdTestAssertMsg(realIm != NULL, "gdImageCreateFromAvif() failed\n"))
+		return 1;
+
+	// Try to decode a non-AVIF file.
+	fp = gdTestFileOpen2("avif", "sunset.png");
+	badIm = gdImageCreateFromAvif(fp);
+	fclose(fp);
+	gdTestAssertMsg(badIm == NULL, "gdImageCreateFromAvif() failed to return NULL when passed a non-AVIF file\n");
+
+	if (badIm)
+		gdImageDestroy(badIm);
+
+	// Try to encode a valid image with bad quality parameters. This should still work.
+
+	rv = gdImageAvifPtrEx(realIm, &size, 400, 10);
+	gdTestAssertMsg(rv != NULL, "gdImageAvifPtrEx() rejected an overly high quality param instead of clamping it to a valid value");
+	gdFree(rv);
+
+	rv = gdImageAvifPtrEx(realIm, &size, -4, 10);
+	gdTestAssertMsg(rv != NULL, "gdImageAvifPtrEx() rejected a negative quality param instead of clamping it to a valid value");
+	gdFree(rv);
+
+	rv = gdImageAvifPtrEx(realIm, &size, 30, 30);
+	gdTestAssertMsg(rv != NULL, "gdImageAvifPtrEx() rejected an overly high speed param instead of clamping it to a valid value");
+	gdFree(rv);
+
+	rv = gdImageAvifPtrEx(realIm, &size, 30, -4);
+	gdTestAssertMsg(rv != NULL, "gdImageAvifPtrEx() rejected a negative speed param instead of clamping it to a valid value");
+	gdFree(rv);
+
+	gdImageDestroy(realIm);
+
+	return gdNumFailures();
+}
diff --git a/tests/avif/compare_avif_to_png.c b/tests/avif/compare_avif_to_png.c
new file mode 100644
index 0000000..6330ea3
--- /dev/null
+++ b/tests/avif/compare_avif_to_png.c
@@ -0,0 +1,92 @@
+/**
+ * File: compare_avif_to_png
+ *
+ * Thorough check for AVIF encoding and decoding.
+ * This test reqiures a set of PNG images that have been losslessly encoded to AVIFs.
+ * For each such image, we encode the PNG into an AVIF, with the GD format as an intermediary,
+ * then compare the resulting AVIF with the original PNG.
+ *
+ * We then do this process in reverse, encoding the AVIF into a PNG,
+ * and compare the resulting PNG with the original AVIF.
+ *
+ * We report any discrepancies in the images, or any other errors that may occur.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include "gd.h"
+#include "gdtest.h"
+
+int main() {
+	FILE *fp;
+	gdImagePtr imFromPng = NULL, imFromAvif = NULL;
+	void *avifImDataPtr = NULL, *pngImDataPtr = NULL;
+	int size;
+	char pngFilename[100], avifFilename[100], *pngFilePath;
+	char errMsg[4096];
+
+	static const char * const filenames[] = {"baboon", "dice_with_alpha", "plum_blossom_12bit", "sunset"};
+	const int filesCount = sizeof(filenames) / sizeof(filenames[0]);
+
+	for (int i = 0; i < filesCount; i++) {
+
+		// First, encode each PNG into an AVIF (with the GD format as an intermediary),
+		// then compare the result with the original PNG.
+		sprintf(pngFilename, "%s.png", filenames[i]);
+
+		fp = gdTestFileOpen2("avif", pngFilename);
+		imFromPng = gdImageCreateFromPng(fp);
+		fclose(fp);
+
+		strcat(strcpy(errMsg, filenames[i]), ".png: gdImageCreateFromPng failed\n");
+		if (!gdTestAssertMsg(imFromPng != NULL, errMsg))
+			goto avif2png;
+
+		strcat(strcpy(errMsg, filenames[i]), ": gdImageAvifPtrEx failed\n");
+		avifImDataPtr = gdImageAvifPtrEx(imFromPng, &size, 100, 0);
+		if (!gdTestAssertMsg(avifImDataPtr != NULL, errMsg))
+			goto avif2png;
+
+		strcat(strcpy(errMsg, filenames[i]), ": gdImageCreateFromAvifPtr failed\n");
+		imFromAvif = gdImageCreateFromAvifPtr(size, avifImDataPtr);
+		if (!gdTestAssertMsg(imFromAvif != NULL, errMsg))
+			goto avif2png;
+
+		strcat(strcpy(errMsg, filenames[i]), ".png: Encoded AVIF image did not match original PNG\n");
+		gdTestAssertMsg(gdAssertImageEquals(imFromPng, imFromAvif), errMsg);
+
+		// Then, decode each AVIF into a GD format, and compare that with the orginal PNG.
+avif2png:
+
+		// Skip this reverse test for now, until we can find images that encode to PNGs losslessly.
+if (0) {
+		sprintf(avifFilename, "%s.avif", filenames[i]);
+		fp = gdTestFileOpen2("avif", avifFilename);
+		imFromAvif = gdImageCreateFromAvif(fp);
+		fclose(fp);
+
+		strcat(strcpy(errMsg, filenames[i]), ".avif: gdImageCreateFromAvif failed\n");
+		if (!gdTestAssertMsg(imFromAvif != NULL, errMsg))
+			continue;
+
+		strcat(strcpy(errMsg, filenames[i]), ".avif: Encoded PNG image did not match original AVIF\n");
+		pngFilePath = gdTestFilePath2("avif", pngFilename);
+		gdTestAssertMsg(gdAssertImageEqualsToFile(pngFilePath, imFromAvif), errMsg);
+		free(pngFilePath);
+}
+	}
+
+	if (imFromPng)
+		gdImageDestroy(imFromPng);
+
+	if (imFromAvif)
+		gdImageDestroy(imFromAvif);
+
+	if (avifImDataPtr)
+		gdFree(avifImDataPtr);
+
+	if (pngImDataPtr)
+		gdFree(pngImDataPtr);
+
+	return gdNumFailures();
+}
diff --git a/tests/avif/dice_with_alpha.avif b/tests/avif/dice_with_alpha.avif
new file mode 100644
index 0000000..dce625b
--- /dev/null
+++ b/tests/avif/dice_with_alpha.avif
diff --git a/tests/avif/dice_with_alpha.png b/tests/avif/dice_with_alpha.png
new file mode 100644
index 0000000..d2809d1
--- /dev/null
+++ b/tests/avif/dice_with_alpha.png
diff --git a/tests/avif/plum_blossom_12bit.avif b/tests/avif/plum_blossom_12bit.avif
new file mode 100644
index 0000000..7959d15
--- /dev/null
+++ b/tests/avif/plum_blossom_12bit.avif
diff --git a/tests/avif/plum_blossom_12bit.png b/tests/avif/plum_blossom_12bit.png
new file mode 100644
index 0000000..e6901e2
--- /dev/null
+++ b/tests/avif/plum_blossom_12bit.png
diff --git a/tests/avif/sunset.avif b/tests/avif/sunset.avif
new file mode 100644
index 0000000..4964558
--- /dev/null
+++ b/tests/avif/sunset.avif
diff --git a/tests/avif/sunset.png b/tests/avif/sunset.png
new file mode 100644
index 0000000..21f45d5
--- /dev/null
+++ b/tests/avif/sunset.png
diff --git a/tests/bmp/.gitignore b/tests/bmp/.gitignore
index 7c4edd0..c2cd2af 100644
--- a/tests/bmp/.gitignore
+++ b/tests/bmp/.gitignore
@@ -2,3 +2,4 @@
 /bmp_null
 /bug00275
 /bug00276
+/bug00450
diff --git a/tests/bmp/CMakeLists.txt b/tests/bmp/CMakeLists.txt
index 82dfb67..0cc1d06 100644
--- a/tests/bmp/CMakeLists.txt
+++ b/tests/bmp/CMakeLists.txt
@@ -1,7 +1,8 @@
 LIST(APPEND TESTS_FILES
-	bmp_im2im
 	bmp_null
 	bug00275
+	bug00450
+	bmp_im2im
 	bug00276
 )
 
diff --git a/tests/bmp/Makemodule.am b/tests/bmp/Makemodule.am
index 27dc7ec..e7908f3 100644
--- a/tests/bmp/Makemodule.am
+++ b/tests/bmp/Makemodule.am
@@ -1,12 +1,10 @@
 libgd_test_programs += \
 	bmp/bmp_null \
 	bmp/bug00275 \
+	bmp/bug00450 \
+	bmp/bmp_im2im \
 	bmp/bug00276
 
-if HAVE_LIBPNG
-libgd_test_programs += \
-	bmp/bmp_im2im
-endif
-
 EXTRA_DIST += \
+	bmp/bug00450.bmp \
 	bmp/CMakeLists.txt
diff --git a/tests/bmp/bug00275.c b/tests/bmp/bug00275.c
index 710c084..775d849 100644
--- a/tests/bmp/bug00275.c
+++ b/tests/bmp/bug00275.c
@@ -6,7 +6,7 @@
 
 
 #ifdef __GNUC__
-#define UNUSED __attribute__((unused))
+#define UNUSED __attribute__((__unused__))
 #else
 #define UNUSED
 #endif
@@ -49,5 +49,7 @@ int main()
 	/* "save" the image as BMP */
 	gdImageBmpCtx(im, &ctx, 2);
 
+	gdImageDestroy(im);
+
 	return gdNumFailures();
 }
diff --git a/tests/bmp/bug00276.c b/tests/bmp/bug00276.c
index 58ca423..dd5d513 100644
--- a/tests/bmp/bug00276.c
+++ b/tests/bmp/bug00276.c
@@ -28,5 +28,7 @@ int main()
 	gdImageDestroy(im_orig);
 	gdImageDestroy(im_saved);
 
+	gdFree(data);
+
 	return gdNumFailures();
 }
diff --git a/tests/bmp/bug00450.bmp b/tests/bmp/bug00450.bmp
new file mode 100644
index 0000000..2db27a3
--- /dev/null
+++ b/tests/bmp/bug00450.bmp
diff --git a/tests/bmp/bug00450.c b/tests/bmp/bug00450.c
new file mode 100644
index 0000000..e048845
--- /dev/null
+++ b/tests/bmp/bug00450.c
@@ -0,0 +1,40 @@
+#include <stdio.h>
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main(void) {
+	char *path = gdTestFilePath("bmp/bug00450.bmp");
+	gdImagePtr im = gdImageCreateFromFile(path);
+	gdTestAssert(im != NULL);
+
+	if (im) {
+		char const ref[] =
+			"#         "
+			"##        "
+			"###       "
+			"####      "
+			"#####     "
+			"######    "
+			"#######   "
+			"########  "
+			"######### "
+			"##########"
+			;
+		int x, y;
+
+		for (y = 0; y < 10; ++y) {
+			for (x = 0; x < 10; ++x) {
+				int const expected_pixel = ref[x + y * 10] == '#';
+				int const actual_pixel = gdImageGetPixel(im, x, y);
+				gdTestAssert(expected_pixel == actual_pixel);
+			}
+		}
+
+		gdImageDestroy(im);
+	}
+
+	free(path);
+
+	return gdNumFailures();
+}
diff --git a/tests/fontconfig/CMakeLists.txt b/tests/fontconfig/CMakeLists.txt
index 159130d..f78c4cf 100644
--- a/tests/fontconfig/CMakeLists.txt
+++ b/tests/fontconfig/CMakeLists.txt
@@ -1,7 +1,9 @@
-IF(FREETYPE_FOUND AND FONTCONFIG_FOUND)
+if(FONTCONFIG_FOUND)
+IF(FREETYPE_FOUND)
 LIST(APPEND TESTS_FILES
     basic
 )
-ENDIF(FREETYPE_FOUND AND FONTCONFIG_FOUND)
+ENDIF(FREETYPE_FOUND)
+ENDIF(FONTCONFIG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/freetype/CMakeLists.txt b/tests/freetype/CMakeLists.txt
index a5d8086..9a1e018 100644
--- a/tests/freetype/CMakeLists.txt
+++ b/tests/freetype/CMakeLists.txt
@@ -1,7 +1,9 @@
 IF(FREETYPE_FOUND)
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	bug00132
 )
+ENDIF(PNG_FOUND)
 ENDIF(FREETYPE_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/freetype/Makemodule.am b/tests/freetype/Makemodule.am
index d252493..a0dda49 100644
--- a/tests/freetype/Makemodule.am
+++ b/tests/freetype/Makemodule.am
@@ -1,7 +1,9 @@
 if HAVE_LIBFREETYPE
+if HAVE_LIBPNG
 libgd_test_programs += \
 	freetype/bug00132
 endif
+endif
 
 EXTRA_DIST += \
 	freetype/CMakeLists.txt \
diff --git a/tests/freetype/bug00132.c b/tests/freetype/bug00132.c
index 713dd2d..42ed5b1 100644
--- a/tests/freetype/bug00132.c
+++ b/tests/freetype/bug00132.c
@@ -11,6 +11,9 @@ int main()
 	char *path;
 	char *ret = NULL;
 
+	/* disable subpixel hinting */
+	putenv("FREETYPE_PROPERTIES=truetype:interpreter-version=35");
+
 	im = gdImageCreateTrueColor(50, 30);
 
 	if (!im) {
diff --git a/tests/gd/.gitignore b/tests/gd/.gitignore
index 5edc65c..8a7d284 100644
--- a/tests/gd/.gitignore
+++ b/tests/gd/.gitignore
@@ -1,3 +1,4 @@
+/bug00383
 /gd_im2im
 /gd_null
 /gd_num_colors
diff --git a/tests/gd/CMakeLists.txt b/tests/gd/CMakeLists.txt
index 3b7ace2..e86c780 100644
--- a/tests/gd/CMakeLists.txt
+++ b/tests/gd/CMakeLists.txt
@@ -1,8 +1,14 @@
 LIST(APPEND TESTS_FILES
-	gd_im2im
+	gd_versiontest
+)
+
+IF(ENABLE_GD_FORMATS)
+LIST(APPEND TESTS_FILES
+	bug00383
 	gd_null
 	gd_num_colors
-	gd_versiontest
+	gd_im2im
 )
+ENDIF(ENABLE_GD_FORMATS)
 
 ADD_GD_TESTS()
diff --git a/tests/gd/Makemodule.am b/tests/gd/Makemodule.am
index e4a741f..4a45bc2 100644
--- a/tests/gd/Makemodule.am
+++ b/tests/gd/Makemodule.am
@@ -1,13 +1,15 @@
 libgd_test_programs += \
-	gd/gd_null \
-	gd/gd_num_colors \
 	gd/gd_versiontest
 
-if HAVE_LIBPNG
+if ENABLE_GD_FORMATS
 libgd_test_programs += \
+	gd/bug00383 \
+	gd/gd_null \
+	gd/gd_num_colors \
 	gd/gd_im2im
 endif
 
 EXTRA_DIST += \
+	gd/bug00383.gd \
 	gd/crafted_num_colors.gd \
 	gd/CMakeLists.txt
diff --git a/tests/gd/bug00383.c b/tests/gd/bug00383.c
new file mode 100644
index 0000000..edcfd05
--- /dev/null
+++ b/tests/gd/bug00383.c
@@ -0,0 +1,32 @@
+/**
+ * Test that invalid transparent colors can't be read
+ *
+ * We're reading a corrupt palette image in GD format, which has only a single
+ * palette entry, but claims that the transparent color would be 1.  We check
+ * that the transparency is simply ignored in this case.
+ *
+ * See also <https://github.com/libgd/libgd/issues/383>
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+    gdImagePtr im;
+    FILE *fp;
+
+    fp = gdTestFileOpen2("gd", "bug00383.gd");
+    gdTestAssert(fp != NULL);
+    im = gdImageCreateFromGd(fp);
+    gdTestAssert(im != NULL);
+    fclose(fp);
+
+    gdTestAssert(gdImageGetTransparent(im) == -1);
+
+    gdImageDestroy(im);
+
+    return gdNumFailures();
+}
diff --git a/tests/gd/bug00383.gd b/tests/gd/bug00383.gd
new file mode 100644
index 0000000..7f8611c
--- /dev/null
+++ b/tests/gd/bug00383.gd
diff --git a/tests/gd2/.gitignore b/tests/gd2/.gitignore
index 136a2d5..a0e2fa3 100644
--- a/tests/gd2/.gitignore
+++ b/tests/gd2/.gitignore
@@ -1,8 +1,14 @@
 /bug_289
+/bug00209
 /bug00309
+/bug00354
+/bug00383
+/createimagefromgd2part
+/createimagefromgd2partptr
 /gd2_empty_file
 /gd2_im2im
 /gd2_null
 /gd2_read
 /gd2_read_corrupt
 /php_bug_72339
+/too_few_image_data
diff --git a/tests/gd2/CMakeLists.txt b/tests/gd2/CMakeLists.txt
index 8fcc906..cc188ca 100644
--- a/tests/gd2/CMakeLists.txt
+++ b/tests/gd2/CMakeLists.txt
@@ -1,12 +1,27 @@
+IF(ENABLE_GD_FORMATS)
+IF(ZLIB_FOUND)
 LIST(APPEND TESTS_FILES
 	bug_289
+	bug00209
 	bug00309
+	bug00354
+	bug00383
+	createimagefromgd2part
+	createimagefromgd2partptr
 	gd2_empty_file
-	gd2_im2im
-	gd2_null
 	php_bug_72339
-	gd2_read
+	gd2_null
 	gd2_read_corrupt
+	too_few_image_data
+	gd2_im2im
+)
+
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	gd2_read
 )
+ENDIF(PNG_FOUND)
+ENDIF(ZLIB_FOUND)
+ENDIF(ENABLE_GD_FORMATS)
 
 ADD_GD_TESTS()
diff --git a/tests/gd2/Makemodule.am b/tests/gd2/Makemodule.am
index d69aee0..5cd29e6 100644
--- a/tests/gd2/Makemodule.am
+++ b/tests/gd2/Makemodule.am
@@ -1,26 +1,37 @@
+if ENABLE_GD_FORMATS
+if HAVE_LIBZ
 libgd_test_programs += \
 	gd2/bug_289 \
+	gd2/bug00209 \
 	gd2/bug00309 \
+	gd2/bug00354 \
+	gd2/bug00383 \
+	gd2/createimagefromgd2part \
+	gd2/createimagefromgd2partptr \
 	gd2/gd2_empty_file \
 	gd2/php_bug_72339 \
-	gd2/gd2_read_corrupt
-
-if HAVE_LIBZ
-libgd_test_programs += \
-	gd2/gd2_null
+	gd2/gd2_null \
+	gd2/gd2_read_corrupt \
+	gd2/too_few_image_data \
+	gd2/gd2_im2im
 
 if HAVE_LIBPNG
 libgd_test_programs += \
-	gd2/gd2_im2im \
 	gd2/gd2_read
 endif
 endif
+endif
 
 EXTRA_DIST += \
 	gd2/CMakeLists.txt \
+	gd2/bug00209.gd2 \
+	gd2/bug00354a.gd2 \
+	gd2/bug00354b.gd2 \
+	gd2/bug00383.gd2 \
 	gd2/conv_gd2_exp.gd2 \
 	gd2/conv_test.gd2 \
 	gd2/conv_test_exp.png \
 	gd2/empty.gd2 \
 	gd2/invalid_header.gd2 \
-	gd2/invalid_neg_size.gd2
+	gd2/invalid_neg_size.gd2 \
+	gd2/too_few_image_data.gd2
diff --git a/tests/gd2/bug00209.c b/tests/gd2/bug00209.c
new file mode 100644
index 0000000..7904d01
--- /dev/null
+++ b/tests/gd2/bug00209.c
@@ -0,0 +1,26 @@
+/**
+ * Regression test for github issue #209
+ *
+ * We're testing that bug00209.gd2, which claims to have 12336 x 48 pixels, but
+ * actually provides not enough image data, is rejected, i.e. that
+ * gdImageCreateFromGd2() returns NULL
+ *
+ * See <https://github.com/libgd/libgd/issues/209>.
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	FILE *fp;
+
+	fp = gdTestFileOpen2("gd2", "bug00209.gd2");
+	gdTestAssert(fp != NULL);
+	im = gdImageCreateFromGd2(fp);
+	gdTestAssert(im == NULL);
+	fclose(fp);
+
+	return gdNumFailures();
+}
diff --git a/tests/gd2/bug00209.gd2 b/tests/gd2/bug00209.gd2
new file mode 100644
index 0000000..1c797d1
--- /dev/null
+++ b/tests/gd2/bug00209.gd2
diff --git a/tests/gd2/bug00354.c b/tests/gd2/bug00354.c
new file mode 100644
index 0000000..1bce091
--- /dev/null
+++ b/tests/gd2/bug00354.c
@@ -0,0 +1,30 @@
+/**
+ * We're testing GD2 image files which report illegal chunk counts. These should
+ * not cause integer overflows or other issues, but instead simply fail to be
+ * loaded.
+ *
+ * See also <https://github.com/libgd/libgd/issues/354>.
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	FILE *fp;
+
+	fp = gdTestFileOpen2("gd2", "bug00354a.gd2");
+	gdTestAssert(fp != NULL);
+	im = gdImageCreateFromGd2(fp);
+	gdTestAssert(im == NULL);
+	fclose(fp);
+
+	fp = gdTestFileOpen2("gd2", "bug00354b.gd2");
+	gdTestAssert(fp != NULL);
+	im = gdImageCreateFromGd2(fp);
+	gdTestAssert(im == NULL);
+	fclose(fp);
+
+	return gdNumFailures();
+}
diff --git a/tests/gd2/bug00354a.gd2 b/tests/gd2/bug00354a.gd2
new file mode 100644
index 0000000..5060bfd
--- /dev/null
+++ b/tests/gd2/bug00354a.gd2
diff --git a/tests/gd2/bug00354b.gd2 b/tests/gd2/bug00354b.gd2
new file mode 100644
index 0000000..8600126
--- /dev/null
+++ b/tests/gd2/bug00354b.gd2
diff --git a/tests/gd2/bug00383.c b/tests/gd2/bug00383.c
new file mode 100644
index 0000000..dbbf661
--- /dev/null
+++ b/tests/gd2/bug00383.c
@@ -0,0 +1,32 @@
+/**
+ * Test that invalid transparent colors can't be read
+ *
+ * We're reading a corrupt palette image in GD2 format, which has only a single
+ * palette entry, but claims that the transparent color would be 1.  We check
+ * that the transparency is simply ignored in this case.
+ *
+ * See also <https://github.com/libgd/libgd/issues/383>
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+    gdImagePtr im;
+    FILE *fp;
+
+    fp = gdTestFileOpen2("gd2", "bug00383.gd2");
+    gdTestAssert(fp != NULL);
+    im = gdImageCreateFromGd2(fp);
+    gdTestAssert(im != NULL);
+    fclose(fp);
+
+    gdTestAssert(gdImageGetTransparent(im) == -1);
+
+    gdImageDestroy(im);
+
+    return gdNumFailures();
+}
diff --git a/tests/gd2/bug00383.gd2 b/tests/gd2/bug00383.gd2
new file mode 100644
index 0000000..dcb164d
--- /dev/null
+++ b/tests/gd2/bug00383.gd2
diff --git a/tests/gd2/bug_289.c b/tests/gd2/bug_289.c
index ad311e9..9ca03cc 100644
--- a/tests/gd2/bug_289.c
+++ b/tests/gd2/bug_289.c
@@ -29,5 +29,7 @@ int main()
     gdTestAssertMsg(buffer[12] == 0, MSG, "1st", 0, buffer[12]);
     gdTestAssertMsg(buffer[13] == GD2_FMT_TRUECOLOR_COMPRESSED, MSG, "2nd", GD2_FMT_TRUECOLOR_COMPRESSED, buffer[13]);
 
+    gdFree(buffer);
+
     return gdNumFailures();
 }
diff --git a/tests/gd2/createimagefromgd2part.c b/tests/gd2/createimagefromgd2part.c
new file mode 100644
index 0000000..0c81ba6
--- /dev/null
+++ b/tests/gd2/createimagefromgd2part.c
@@ -0,0 +1,35 @@
+/**
+ *Base test for gdImageCreateFromGd2Part()
+ */
+#include "gd.h"
+#include "gdtest.h"
+#include <stdio.h>
+#include <stdlib.h>
+
+int main()
+{
+	gdImagePtr im;
+	FILE *p;
+	int expected_color = 0xffffff;
+	int actual_color = 0;
+
+	p = gdTestFileOpen2("gd2", "conv_test.gd2");
+
+	if (!p) {
+		gdTestErrorMsg("failed, connot open gd2 file: conv_test.gd2");
+		return 1;
+	}
+
+	im = gdImageCreateFromGd2Part(p, 3, 3, 3, 3);
+	fclose(p);
+
+	if (!im) {
+		return 1;
+	}
+
+	actual_color = gdImageGetPixel(im, 2, 2);
+	gdImageDestroy(im);
+	gdTestAssert(expected_color == actual_color);
+
+	return gdNumFailures();
+}
diff --git a/tests/gd2/createimagefromgd2partptr.c b/tests/gd2/createimagefromgd2partptr.c
new file mode 100644
index 0000000..e432874
--- /dev/null
+++ b/tests/gd2/createimagefromgd2partptr.c
@@ -0,0 +1,59 @@
+/**
+ * Base test for gdImageCreateFromGd2PartPtr()
+ */
+#include "gd.h"
+#include "gdtest.h"
+#include <stdio.h>
+
+int main()
+{
+	FILE *p;
+	gdImagePtr im, partim;
+	void *pg;
+	int size = 0;
+	int status = 0;
+	int actual_color = 0;
+	int expected_color = 0xffffff;
+
+	p = gdTestFileOpen2("gd2", "conv_test.gd2");
+	if (!p) {
+		gdTestErrorMsg("failed, cannot open gd2 file:conv_test.gd2");
+		return 1;
+	}
+
+	im = gdImageCreateFromGd2(p);
+	fclose(p);
+
+	if (!im) {
+		gdTestErrorMsg("failed, cannot create gd2 file.");
+		return 1;
+	}
+
+	pg = gdImageGd2Ptr(im, (GD2_CHUNKSIZE_MIN + GD2_CHUNKSIZE_MAX) / 2, GD2_FMT_COMPRESSED, &size);
+	if (!pg) {
+		status = 1;
+		goto done1;
+	}
+
+	if (size <= 0) {
+		status = 1;
+		goto done0;
+	}
+
+	partim =  gdImageCreateFromGd2PartPtr(size, pg, 3, 3, 3, 3);
+	if (!partim) {
+		status = 1;
+		goto done0;
+	}
+
+	actual_color = gdImageGetPixel(partim, 2, 2);
+	status = (expected_color == actual_color) ? 0 : 1;
+	gdImageDestroy(partim);
+
+done0:
+	gdFree(pg);
+done1:
+	gdImageDestroy(im);
+
+	return status;
+}
diff --git a/tests/gd2/gd2_read.c b/tests/gd2/gd2_read.c
index 8ce8bd1..9f2b808 100644
--- a/tests/gd2/gd2_read.c
+++ b/tests/gd2/gd2_read.c
@@ -33,17 +33,18 @@ int main(int argc, char *argv[])
 			fp = gdTestFileOpen2("gd2", path_exp[i]);
 			if (!fp) {
 				gdTestErrorMsg("failed, cannot open file: %s\n", path_exp[i]);
+				gdImageDestroy(im);
 				return 1;
 			}
 			exp = gdImageCreateFromPng(fp);
 			if (!gdAssertImageEquals(exp, im)) {
 				gdTestErrorMsg("image %s differs from expected result\n", path[i]);
-				gdImageDestroy(im);
 				error = 1;
 			}
 			if (exp) {
 				gdImageDestroy(exp);
 			}
+			gdImageDestroy(im);
 		} else {
 			/* expected to fail */
 			if (im) {
diff --git a/tests/gd2/php_bug_72339.c b/tests/gd2/php_bug_72339.c
index 7ce6028..8217c87 100644
--- a/tests/gd2/php_bug_72339.c
+++ b/tests/gd2/php_bug_72339.c
@@ -29,7 +29,7 @@ int main()
 
 	im = gdImageCreateFromGd2(fp);
 	fclose(fp);
-	
+
 	gdTestAssertMsg(im == NULL, "Image should have failed to be loaded\n");
 
 	return gdNumFailures();
diff --git a/tests/gd2/too_few_image_data.c b/tests/gd2/too_few_image_data.c
new file mode 100644
index 0000000..3153a08
--- /dev/null
+++ b/tests/gd2/too_few_image_data.c
@@ -0,0 +1,22 @@
+/*
+too_few_image_data.gd2 claims to have a size of 12336x48 pixels, but doesn't
+provide as much image data. We test that gdImageCreateFromGd2Ctx() returns NULL
+in this case.
+*/
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+    gdImagePtr im;
+    FILE *fp;
+
+    fp = gdTestFileOpen2("gd2", "too_few_image_data.gd2");
+    gdTestAssert(fp != NULL);
+    im = gdImageCreateFromGd2(fp);
+    gdTestAssert(im == NULL);
+    fclose(fp);
+
+    return gdNumFailures();
+}
diff --git a/tests/gd2/too_few_image_data.gd2 b/tests/gd2/too_few_image_data.gd2
new file mode 100644
index 0000000..1c797d1
--- /dev/null
+++ b/tests/gd2/too_few_image_data.gd2
diff --git a/tests/gdimagearc/CMakeLists.txt b/tests/gdimagearc/CMakeLists.txt
index 77117fb..fc8ca57 100644
--- a/tests/gdimagearc/CMakeLists.txt
+++ b/tests/gdimagearc/CMakeLists.txt
@@ -1,5 +1,7 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	bug00079
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagebrightness/CMakeLists.txt b/tests/gdimagebrightness/CMakeLists.txt
index 381c74d..802c382 100644
--- a/tests/gdimagebrightness/CMakeLists.txt
+++ b/tests/gdimagebrightness/CMakeLists.txt
@@ -1,5 +1,7 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	basic
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagebrightness/basic.c b/tests/gdimagebrightness/basic.c
index 8c3a73c..dfed242 100644
--- a/tests/gdimagebrightness/basic.c
+++ b/tests/gdimagebrightness/basic.c
@@ -1,41 +1,37 @@
-/**

- * Basic test for gdImageBrightness()

- */

-

-

-#include "gd.h"

-#include "gdtest.h"

-

-

-static void test_brightness(int brightness);

-

-

-int main()

-{

-    test_brightness(+100);

-    test_brightness(-100);

-

-    return gdNumFailures();

-}

-

-

-static void test_brightness(int brightness)

-{

-    gdImagePtr im;

-    FILE *fp;

-    char basename[256];

-    char *path;

-

-    fp = gdTestFileOpen2("gdimagebrightness", "basic.png");

-    im = gdImageCreateFromPng(fp);

-    fclose(fp);

-

-    gdImageBrightness(im, brightness);

-

-    sprintf(basename, "basic%+03d.png", brightness);

-    path = gdTestFilePath2("gdimagebrightness", basename);

-    gdAssertImageEqualsToFile(path, im);

-    gdFree(path);

-

-    gdImageDestroy(im);

-}

+/**
+ * Basic test for gdImageBrightness()
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+static void test_brightness(int brightness);
+
+int main()
+{
+	test_brightness(+100);
+	test_brightness(-100);
+
+	return gdNumFailures();
+}
+
+static void test_brightness(int brightness)
+{
+	gdImagePtr im;
+	FILE *fp;
+	char basename[256];
+	char *path;
+
+	fp = gdTestFileOpen2("gdimagebrightness", "basic.png");
+	im = gdImageCreateFromPng(fp);
+	fclose(fp);
+
+	gdImageBrightness(im, brightness);
+
+	sprintf(basename, "basic%+03d.png", brightness);
+	path = gdTestFilePath2("gdimagebrightness", basename);
+	gdAssertImageEqualsToFile(path, im);
+	gdFree(path);
+
+	gdImageDestroy(im);
+}
diff --git a/tests/gdimageclone/.gitignore b/tests/gdimageclone/.gitignore
index a70782d..f4129cc 100644
--- a/tests/gdimageclone/.gitignore
+++ b/tests/gdimageclone/.gitignore
@@ -1 +1,2 @@
 /bug00300
+/style
diff --git a/tests/gdimageclone/CMakeLists.txt b/tests/gdimageclone/CMakeLists.txt
index e6ccc31..662f4e9 100644
--- a/tests/gdimageclone/CMakeLists.txt
+++ b/tests/gdimageclone/CMakeLists.txt
@@ -1,5 +1,6 @@
 LIST(APPEND TESTS_FILES
 	bug00300
+	style
 )
 
 ADD_GD_TESTS()
diff --git a/tests/gdimageclone/Makemodule.am b/tests/gdimageclone/Makemodule.am
index 4b1b54c..51abf5c 100644
--- a/tests/gdimageclone/Makemodule.am
+++ b/tests/gdimageclone/Makemodule.am
@@ -1,5 +1,6 @@
 libgd_test_programs += \
-	gdimageclone/bug00300
+	gdimageclone/bug00300 \
+	gdimageclone/style
 
 EXTRA_DIST += \
 	gdimageclone/CMakeLists.txt
diff --git a/tests/gdimageclone/style.c b/tests/gdimageclone/style.c
new file mode 100644
index 0000000..c2b246e
--- /dev/null
+++ b/tests/gdimageclone/style.c
@@ -0,0 +1,30 @@
+/**
+ * Cloning an image should exactly reproduce all style related data
+ */
+
+
+#include <string.h>
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+    gdImagePtr im, clone;
+    int style[] = {0, 0, 0};
+
+    im = gdImageCreate(8, 8);
+    gdImageSetStyle(im, style, sizeof(style)/sizeof(style[0]));
+
+    clone = gdImageClone(im);
+    gdTestAssert(clone != NULL);
+
+    gdTestAssert(clone->styleLength == im->styleLength);
+    gdTestAssert(clone->stylePos == im->stylePos);
+    gdTestAssert(!memcmp(clone->style, im->style, sizeof(style)/sizeof(style[0])));
+
+    gdImageDestroy(clone);
+    gdImageDestroy(im);
+
+    return gdNumFailures();
+}
diff --git a/tests/gdimagecolor/CMakeLists.txt b/tests/gdimagecolor/CMakeLists.txt
index 381c74d..802c382 100644
--- a/tests/gdimagecolor/CMakeLists.txt
+++ b/tests/gdimagecolor/CMakeLists.txt
@@ -1,5 +1,7 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	basic
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagecolor/basic.c b/tests/gdimagecolor/basic.c
index 2ad0f3c..86c0aff 100644
--- a/tests/gdimagecolor/basic.c
+++ b/tests/gdimagecolor/basic.c
@@ -1,29 +1,27 @@
-/**

- * Basic test for gdImageColor()

- */

-

-

-#include "gd.h"

-#include "gdtest.h"

-

-

-int main()

-{

-    gdImagePtr im;

-    FILE *fp;

-    char *path;

-

-    fp = gdTestFileOpen2("gdimagecolor", "basic.png");

-    im = gdImageCreateFromPng(fp);

-    fclose(fp);

-

-    gdImageColor(im, 127, -127, -127, 0);

-

-    path = gdTestFilePath2("gdimagecolor", "basic_exp.png");

-    gdAssertImageEqualsToFile(path, im);

-    gdFree(path);

-

-    gdImageDestroy(im);

-

-    return gdNumFailures();

-}

+/**
+ * Basic test for gdImageColor()
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	FILE *fp;
+	char *path;
+
+	fp = gdTestFileOpen2("gdimagecolor", "basic.png");
+	im = gdImageCreateFromPng(fp);
+	fclose(fp);
+
+	gdImageColor(im, 127, -127, -127, 0);
+
+	path = gdTestFilePath2("gdimagecolor", "basic_exp.png");
+	gdAssertImageEqualsToFile(path, im);
+	gdFree(path);
+
+	gdImageDestroy(im);
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimagecolorclosest/Makemodule.am b/tests/gdimagecolorclosest/Makemodule.am
index f4da8be..be42204 100644
--- a/tests/gdimagecolorclosest/Makemodule.am
+++ b/tests/gdimagecolorclosest/Makemodule.am
@@ -1,7 +1,5 @@
-if HAVE_LIBPNG
 libgd_test_programs += \
 	gdimagecolorclosest/gdimagecolorclosest
-endif
 
 EXTRA_DIST += \
 	gdimagecolorclosest/CMakeLists.txt
diff --git a/tests/gdimagecolorclosesthwb/.gitignore b/tests/gdimagecolorclosesthwb/.gitignore
new file mode 100644
index 0000000..f46016c
--- /dev/null
+++ b/tests/gdimagecolorclosesthwb/.gitignore
@@ -0,0 +1 @@
+/gdImageColorClosestHWB
diff --git a/tests/gdimagecolorclosesthwb/CMakeLists.txt b/tests/gdimagecolorclosesthwb/CMakeLists.txt
new file mode 100644
index 0000000..7a8afdc
--- /dev/null
+++ b/tests/gdimagecolorclosesthwb/CMakeLists.txt
@@ -0,0 +1,7 @@
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	gdImageColorClosestHWB
+)
+ENDIF(PNG_FOUND)
+
+ADD_GD_TESTS()
diff --git a/tests/gdimagecolorclosesthwb/Makemodule.am b/tests/gdimagecolorclosesthwb/Makemodule.am
new file mode 100644
index 0000000..14eddbd
--- /dev/null
+++ b/tests/gdimagecolorclosesthwb/Makemodule.am
@@ -0,0 +1,7 @@
+if HAVE_LIBPNG
+libgd_test_programs += \
+	gdimagecolorclosesthwb/gdImageColorClosestHWB
+endif
+
+EXTRA_DIST += \
+	gdimagecolorclosesthwb/CMakeLists.txt
diff --git a/tests/gdimagecolorclosesthwb/gdImageColorClosestHWB.c b/tests/gdimagecolorclosesthwb/gdImageColorClosestHWB.c
new file mode 100644
index 0000000..ab20187
--- /dev/null
+++ b/tests/gdimagecolorclosesthwb/gdImageColorClosestHWB.c
@@ -0,0 +1,26 @@
+/**
+  * Basic test for gdImageColorClosestHWB()
+  **/
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	FILE *fp;
+
+	fp = gdTestFileOpen2("gdimageflip", "remi.png");
+	im = gdImageCreateFromPng(fp);
+	fclose(fp);
+
+	int result = gdImageColorClosestHWB(im, 255, 0, 255);
+
+	if (gdTestAssert(result <= 0))
+	{
+		gdImageDestroy(im);
+		return 1;
+	}
+
+	gdImageDestroy(im);
+	return 0;
+}
diff --git a/tests/gdimagecolorexact/Makemodule.am b/tests/gdimagecolorexact/Makemodule.am
index 835b25e..7427999 100644
--- a/tests/gdimagecolorexact/Makemodule.am
+++ b/tests/gdimagecolorexact/Makemodule.am
@@ -1,7 +1,5 @@
-if HAVE_LIBPNG
 libgd_test_programs += \
 	gdimagecolorexact/gdimagecolorexact
-endif
 
 EXTRA_DIST += \
 	gdimagecolorexact/CMakeLists.txt
diff --git a/tests/gdimagecolormatch/.gitignore b/tests/gdimagecolormatch/.gitignore
new file mode 100644
index 0000000..f68c491
--- /dev/null
+++ b/tests/gdimagecolormatch/.gitignore
@@ -0,0 +1,2 @@
+/cve_2019_6977
+/gdimagecolormatch
diff --git a/tests/gdimagecolormatch/CMakeLists.txt b/tests/gdimagecolormatch/CMakeLists.txt
new file mode 100644
index 0000000..857b99a
--- /dev/null
+++ b/tests/gdimagecolormatch/CMakeLists.txt
@@ -0,0 +1,6 @@
+LIST(APPEND TESTS_FILES
+	cve_2019_6977
+	gdimagecolormatch
+)
+
+ADD_GD_TESTS()
diff --git a/tests/gdimagecolormatch/Makemodule.am b/tests/gdimagecolormatch/Makemodule.am
new file mode 100644
index 0000000..4ed48ce
--- /dev/null
+++ b/tests/gdimagecolormatch/Makemodule.am
@@ -0,0 +1,6 @@
+libgd_test_programs += \
+	gdimagecolormatch/cve_2019_6977 \
+	gdimagecolormatch/gdimagecolormatch
+
+EXTRA_DIST += \
+	gdimagecolormatch/CMakeLists.txt
diff --git a/tests/gdimagecolormatch/cve_2019_6977.c b/tests/gdimagecolormatch/cve_2019_6977.c
new file mode 100644
index 0000000..fdd7af5
--- /dev/null
+++ b/tests/gdimagecolormatch/cve_2019_6977.c
@@ -0,0 +1,25 @@
+/**
+ * Test for CVE-2019-6977
+ */
+
+#include "gd.h"
+
+int main()
+{
+	gdImagePtr im1;
+	gdImagePtr im2;
+
+	im1 = gdImageCreateTrueColor(0xfff, 0xfff);
+	im2 = gdImageCreate(0xfff, 0xfff);
+	if (gdImageColorAllocate(im2, 0, 0, 0) < 0)
+	{
+		gdImageDestroy(im1);
+		gdImageDestroy(im2);
+		return 1;
+	}
+	gdImageSetPixel(im2, 0, 0, 255);
+	gdImageColorMatch(im1, im2);
+	gdImageDestroy(im1);
+	gdImageDestroy(im2);
+	return 0;
+}
diff --git a/tests/gdimagecolormatch/gdimagecolormatch.c b/tests/gdimagecolormatch/gdimagecolormatch.c
new file mode 100644
index 0000000..f59c769
--- /dev/null
+++ b/tests/gdimagecolormatch/gdimagecolormatch.c
@@ -0,0 +1,32 @@
+/**
+ * Basic test for gdImageColorMatch()
+ **/
+#include "gd.h"
+#include "gdtest.h"
+
+int main(){
+	gdImagePtr im1, im2;
+
+	im1 = gdImageCreateTrueColor(80, 80);
+	im2 = gdImageCreate(80, 80);
+
+	gdImageColorAllocate(im1, 255, 36, 74);
+
+	gdImageColorAllocate(im2, 255, 36, 74);
+	gdImageColorAllocate(im2, 40, 0, 240);
+	gdImageColorAllocate(im2, 255, 100, 255);
+	gdImageColorAllocate(im2, 80, 60, 44);
+
+	int ifMatch = gdImageColorMatch(im1, im2);
+
+	gdImageDestroy(im1);
+	gdImageDestroy(im2);
+
+	if (gdTestAssert(ifMatch != 0))
+	{
+		gdTestErrorMsg("gdImageColorMatch failed.\n");
+		return 1;
+	}
+
+	return 0;
+}
diff --git a/tests/gdimagecolorreplace/Makemodule.am b/tests/gdimagecolorreplace/Makemodule.am
index a8badb0..3ea38e5 100644
--- a/tests/gdimagecolorreplace/Makemodule.am
+++ b/tests/gdimagecolorreplace/Makemodule.am
@@ -1,7 +1,5 @@
-if HAVE_LIBPNG
 libgd_test_programs += \
 	gdimagecolorreplace/gdimagecolorreplace
-endif
 
 EXTRA_DIST += \
 	gdimagecolorreplace/CMakeLists.txt
diff --git a/tests/gdimagecolorresolve/Makemodule.am b/tests/gdimagecolorresolve/Makemodule.am
index 316484c..a3e9442 100644
--- a/tests/gdimagecolorresolve/Makemodule.am
+++ b/tests/gdimagecolorresolve/Makemodule.am
@@ -1,7 +1,5 @@
-if HAVE_LIBPNG
 libgd_test_programs += \
 	gdimagecolorresolve/gdimagecolorresolve
-endif
 
 EXTRA_DIST += \
 	gdimagecolorresolve/CMakeLists.txt
diff --git a/tests/gdimagecompare/.gitignore b/tests/gdimagecompare/.gitignore
new file mode 100755
index 0000000..312a8c8
--- /dev/null
+++ b/tests/gdimagecompare/.gitignore
@@ -0,0 +1 @@
+/gdimagecompare
diff --git a/tests/gdimagecompare/CMakeLists.txt b/tests/gdimagecompare/CMakeLists.txt
new file mode 100644
index 0000000..2974a07
--- /dev/null
+++ b/tests/gdimagecompare/CMakeLists.txt
@@ -0,0 +1,4 @@
+LIST(APPEND TESTS_FILES
+	gdimagecompare
+)
+ADD_GD_TESTS()
diff --git a/tests/gdimagecompare/Makemodule.am b/tests/gdimagecompare/Makemodule.am
new file mode 100644
index 0000000..b4b0ebb
--- /dev/null
+++ b/tests/gdimagecompare/Makemodule.am
@@ -0,0 +1,5 @@
+libgd_test_programs += \
+	gdimagecompare/gdimagecompare
+
+EXTRA_DIST += \
+	gdimagecompare/CMakeLists.txt
diff --git a/tests/gdimagecompare/gdimagecompare.c b/tests/gdimagecompare/gdimagecompare.c
new file mode 100644
index 0000000..0e8367a
--- /dev/null
+++ b/tests/gdimagecompare/gdimagecompare.c
@@ -0,0 +1,56 @@
+/**
+ * Base test for gdImageCompare()
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im1;
+	gdImagePtr im2;
+	int black;
+	int red1, red2;
+	int yellow1, yellow2;
+	int white;
+	int blue;
+	int ret;
+
+	im1 = gdImageCreate(128, 128);
+	im2 = gdImageCreateTrueColor(256, 256);
+
+	/* Set different interlace */
+	gdImageInterlace(im1, 1);
+	gdImageInterlace(im2, 2);
+
+	/* Set different transparent */
+	gdImageColorTransparent(im1, 10);
+	gdImageColorTransparent(im2, 20);
+
+	/* Allocate different color number */
+	black = gdImageColorAllocate(im1, 0, 0, 0);
+	red1 = gdImageColorAllocate(im1, 255, 0, 0);
+	yellow1 = gdImageColorAllocate(im1, 255, 255, 0);
+	red2 = gdImageColorAllocate(im2, 255, 0, 0);
+	yellow2 = gdImageColorAllocate(im2, 255, 255, 0);
+	white = gdImageColorAllocate(im2, 255, 255, 255);
+	blue = gdImageColorAllocate(im2, 0, 0, 255);
+
+	/* Filled different color */
+	gdImageFilledRectangle(im1, 0, 0, 127, 8, black);
+	gdImageFilledRectangle(im1, 9, 0, 127, 16, red1);
+	gdImageFilledRectangle(im1, 17, 0, 127, 24, yellow1);
+	gdImageFilledRectangle(im2, 0, 0, 127, 8, red2);
+	gdImageFilledRectangle(im2, 9, 0, 127, 16, yellow2);
+	gdImageFilledRectangle(im2, 17, 0, 127, 24, white);
+	gdImageFilledRectangle(im2, 25, 0, 127, 32, blue);
+
+	ret = gdImageCompare(im1, im2);
+
+	gdTestAssert(ret == (GD_CMP_INTERLACE | GD_CMP_TRANSPARENT | GD_CMP_TRUECOLOR | GD_CMP_SIZE_X | GD_CMP_SIZE_Y | GD_CMP_COLOR | GD_CMP_IMAGE | GD_CMP_NUM_COLORS));
+
+	gdImageDestroy(im1);
+	gdImageDestroy(im2);
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimagecontrast/CMakeLists.txt b/tests/gdimagecontrast/CMakeLists.txt
index 381c74d..802c382 100644
--- a/tests/gdimagecontrast/CMakeLists.txt
+++ b/tests/gdimagecontrast/CMakeLists.txt
@@ -1,5 +1,7 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	basic
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagecontrast/basic.c b/tests/gdimagecontrast/basic.c
index d001bf9..ef1f44a 100644
--- a/tests/gdimagecontrast/basic.c
+++ b/tests/gdimagecontrast/basic.c
@@ -1,41 +1,37 @@
-/**

- * Basic test for gdImageContrast()

- */

-

-

-#include "gd.h"

-#include "gdtest.h"

-

-

-static void test_contrast(double contrast);

-

-

-int main()

-{

-    test_contrast(+50.0);

-    test_contrast(-50.0);

-

-    return gdNumFailures();

-}

-

-

-static void test_contrast(double contrast)

-{

-    gdImagePtr im;

-    FILE *fp;

-    char basename[256];

-    char *path;

-

-    fp = gdTestFileOpen2("gdimagecontrast", "basic.png");

-    im = gdImageCreateFromPng(fp);

-    fclose(fp);

-

-    gdImageContrast(im, contrast);

-

-    sprintf(basename, "basic%+03.0f.png", contrast);

-    path = gdTestFilePath2("gdimagecontrast", basename);

-    gdAssertImageEqualsToFile(path, im);

-    gdFree(path);

-

-    gdImageDestroy(im);

-}

+/**
+ * Basic test for gdImageContrast()
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+static void test_contrast(double contrast);
+
+int main()
+{
+	test_contrast(+50.0);
+	test_contrast(-50.0);
+
+	return gdNumFailures();
+}
+
+static void test_contrast(double contrast)
+{
+	gdImagePtr im;
+	FILE *fp;
+	char basename[256];
+	char *path;
+
+	fp = gdTestFileOpen2("gdimagecontrast", "basic.png");
+	im = gdImageCreateFromPng(fp);
+	fclose(fp);
+
+	gdImageContrast(im, contrast);
+
+	sprintf(basename, "basic%+03.0f.png", contrast);
+	path = gdTestFilePath2("gdimagecontrast", basename);
+	gdAssertImageEqualsToFile(path, im);
+	gdFree(path);
+
+	gdImageDestroy(im);
+}
diff --git a/tests/gdimageconvolution/.gitignore b/tests/gdimageconvolution/.gitignore
index 1ffd796..6665df0 100644
--- a/tests/gdimageconvolution/.gitignore
+++ b/tests/gdimageconvolution/.gitignore
@@ -1 +1,2 @@
 /basic
+/bug00369
diff --git a/tests/gdimageconvolution/CMakeLists.txt b/tests/gdimageconvolution/CMakeLists.txt
index 381c74d..dc1fc51 100644
--- a/tests/gdimageconvolution/CMakeLists.txt
+++ b/tests/gdimageconvolution/CMakeLists.txt
@@ -1,5 +1,9 @@
+LIST(APPEND TESTS_FILES bug00369)
+
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	basic
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimageconvolution/Makemodule.am b/tests/gdimageconvolution/Makemodule.am
index 8f65b0f..df5249d 100644
--- a/tests/gdimageconvolution/Makemodule.am
+++ b/tests/gdimageconvolution/Makemodule.am
@@ -1,3 +1,6 @@
+libgd_test_programs += \
+	gdimageconvolution/bug00369
+
 if HAVE_LIBPNG
 libgd_test_programs += \
 	gdimageconvolution/basic
diff --git a/tests/gdimageconvolution/basic.c b/tests/gdimageconvolution/basic.c
index 7ca98be..5fe308c 100644
--- a/tests/gdimageconvolution/basic.c
+++ b/tests/gdimageconvolution/basic.c
@@ -1,62 +1,55 @@
-/**

- * Basic test for gdImageConvolution() and related functions

- */

-

-

-#include "gd.h"

-#include "gdtest.h"

-

-

-static void test_convolution(void (*convolution_func)(gdImagePtr im), const char *expected)

-{

-    gdImagePtr im;

-    FILE *fp;

-    char *path;

-

-    fp = gdTestFileOpen2("gdimageconvolution", "basic.png");

-    im = gdImageCreateFromPng(fp);

-    fclose(fp);

-

-    convolution_func(im);

-

-    path = gdTestFilePath2("gdimageconvolution", expected);

-    gdAssertImageEqualsToFile(path, im);

-    gdFree(path);

-

-    gdImageDestroy(im);

-}

-

-

-static void test_edge_detect_quick(gdImagePtr im)

-{

-    gdImageEdgeDetectQuick(im);

-}

-

-

-static void test_smooth(gdImagePtr im)

-{

-    gdImageSmooth(im, 5);

-}

-

-

-static void test_emboss(gdImagePtr im)

-{

-    gdImageEmboss(im);

-}

-

-

-static void test_mean_removal(gdImagePtr im)

-{

-    gdImageMeanRemoval(im);

-}

-

-

-int main()

-{

-    test_convolution(&test_edge_detect_quick, "basic_edge_detect_quick.png");

-    test_convolution(&test_smooth, "basic_smooth.png");

-    test_convolution(&test_emboss, "basic_emboss.png");

-    test_convolution(&test_mean_removal, "basic_mean_removal.png");

-

-    return gdNumFailures();

-}

+/**
+ * Basic test for gdImageConvolution() and related functions
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+static void test_convolution(void (*convolution_func)(gdImagePtr im), const char *expected)
+{
+	gdImagePtr im;
+	FILE *fp;
+	char *path;
+
+	fp = gdTestFileOpen2("gdimageconvolution", "basic.png");
+	im = gdImageCreateFromPng(fp);
+	fclose(fp);
+
+	convolution_func(im);
+
+	path = gdTestFilePath2("gdimageconvolution", expected);
+	gdAssertImageEqualsToFile(path, im);
+	gdFree(path);
+
+	gdImageDestroy(im);
+}
+
+static void test_edge_detect_quick(gdImagePtr im)
+{
+	gdImageEdgeDetectQuick(im);
+}
+
+static void test_smooth(gdImagePtr im)
+{
+	gdImageSmooth(im, 5);
+}
+
+static void test_emboss(gdImagePtr im)
+{
+	gdImageEmboss(im);
+}
+
+static void test_mean_removal(gdImagePtr im)
+{
+	gdImageMeanRemoval(im);
+}
+
+int main()
+{
+	test_convolution(&test_edge_detect_quick, "basic_edge_detect_quick.png");
+	test_convolution(&test_smooth, "basic_smooth.png");
+	test_convolution(&test_emboss, "basic_emboss.png");
+	test_convolution(&test_mean_removal, "basic_mean_removal.png");
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimageconvolution/bug00369.c b/tests/gdimageconvolution/bug00369.c
new file mode 100644
index 0000000..631cb7a
--- /dev/null
+++ b/tests/gdimageconvolution/bug00369.c
@@ -0,0 +1,28 @@
+/**
+ * Test Issue #369 for gdImageConvolution()
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	float matrix[3][3] = {
+		{1, 0, 1},
+		{0, 5, 0},
+		{1, 0, 0}
+	};
+
+	im = gdImageCreateTrueColor(40, 40);
+	gdImageAlphaBlending(im, gdEffectReplace);
+	gdImageFilledRectangle(im, 0, 0, 39, 39, 0x7FFFFFFF);
+	gdImageFilledEllipse(im, 19, 19, 20, 20, 0x00FF00);
+
+	gdImageConvolution(im, matrix, 9, 1);
+	gdTestAssert(0x7F010101 == gdImageGetPixel(im, 0, 0));
+
+	gdImageDestroy(im);
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimagecopy/CMakeLists.txt b/tests/gdimagecopy/CMakeLists.txt
index d9d0eda..f586300 100644
--- a/tests/gdimagecopy/CMakeLists.txt
+++ b/tests/gdimagecopy/CMakeLists.txt
@@ -1,6 +1,11 @@
 LIST(APPEND TESTS_FILES
 	bug00007
+)
+
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
 	bug00081
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagecopymerge/.gitignore b/tests/gdimagecopymerge/.gitignore
new file mode 100644
index 0000000..c56b41b
--- /dev/null
+++ b/tests/gdimagecopymerge/.gitignore
@@ -0,0 +1 @@
+/gdimagecopymerge
diff --git a/tests/gdimagecopymerge/CMakeLists.txt b/tests/gdimagecopymerge/CMakeLists.txt
new file mode 100644
index 0000000..df9bdc6
--- /dev/null
+++ b/tests/gdimagecopymerge/CMakeLists.txt
@@ -0,0 +1,7 @@
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	gdimagecopymerge
+)
+ENDIF(PNG_FOUND)
+
+ADD_GD_TESTS()
diff --git a/tests/gdimagecopymerge/Makemodule.am b/tests/gdimagecopymerge/Makemodule.am
new file mode 100644
index 0000000..6751168
--- /dev/null
+++ b/tests/gdimagecopymerge/Makemodule.am
@@ -0,0 +1,8 @@
+if HAVE_LIBPNG
+libgd_test_programs += \
+	gdimagecopymerge/gdimagecopymerge
+endif
+
+EXTRA_DIST += \
+	gdimagecopymerge/CMakeLists.txt \
+	gdimagecopymerge/gdimagecopymerge_exp.png
diff --git a/tests/gdimagecopymerge/gdimagecopymerge.c b/tests/gdimagecopymerge/gdimagecopymerge.c
new file mode 100644
index 0000000..9f08020
--- /dev/null
+++ b/tests/gdimagecopymerge/gdimagecopymerge.c
@@ -0,0 +1,38 @@
+/**
+ * Basic test for gdImageCopyMerge()
+ */
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr dst = NULL;
+	gdImagePtr src = NULL;
+	int error = 0;
+
+	dst = gdImageCreate(100, 100);
+	src = gdImageCreate(50, 50);
+
+	if (gdTestAssert(!dst)) {
+		error = 1;
+		goto done;
+	}
+	if (gdTestAssert(!src)) {
+		error = 1;
+		goto done;
+	}
+
+	gdImageColorAllocate(src, 255, 255, 255);
+	gdImageColorAllocate(dst, 0, 0, 0);
+	gdImageCopyMerge(dst, src, 25, 25, 0, 0, 50, 50, 50);
+
+	if (!gdAssertImageEqualsToFile("gdimagecopymerge/gdimagecopymerge_exp.png", dst)) {
+		error = 1;
+	}
+
+done:
+	gdImageDestroy(dst);
+	gdImageDestroy(src);
+
+	return error;
+}
diff --git a/tests/gdimagecopymerge/gdimagecopymerge_exp.png b/tests/gdimagecopymerge/gdimagecopymerge_exp.png
new file mode 100644
index 0000000..1830281
--- /dev/null
+++ b/tests/gdimagecopymerge/gdimagecopymerge_exp.png
diff --git a/tests/gdimagecopymergegray/.gitignore b/tests/gdimagecopymergegray/.gitignore
new file mode 100644
index 0000000..a85d2ac
--- /dev/null
+++ b/tests/gdimagecopymergegray/.gitignore
@@ -0,0 +1 @@
+/gdimagecopymergegray
diff --git a/tests/gdimagecopymergegray/CMakeLists.txt b/tests/gdimagecopymergegray/CMakeLists.txt
new file mode 100644
index 0000000..e0656ef
--- /dev/null
+++ b/tests/gdimagecopymergegray/CMakeLists.txt
@@ -0,0 +1,7 @@
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	gdimagecopymergegray
+)
+ENDIF(PNG_FOUND)
+
+ADD_GD_TESTS()
diff --git a/tests/gdimagecopymergegray/Makemodule.am b/tests/gdimagecopymergegray/Makemodule.am
new file mode 100644
index 0000000..6856d75
--- /dev/null
+++ b/tests/gdimagecopymergegray/Makemodule.am
@@ -0,0 +1,8 @@
+if HAVE_LIBPNG
+libgd_test_programs += \
+	gdimagecopymergegray/gdimagecopymergegray
+endif
+
+EXTRA_DIST += \
+	gdimagecopymergegray/CMakeLists.txt \
+	gdimagecopymergegray/gdimagecopymergegray_exp.png
diff --git a/tests/gdimagecopymergegray/gdimagecopymergegray.c b/tests/gdimagecopymergegray/gdimagecopymergegray.c
new file mode 100644
index 0000000..34a8923
--- /dev/null
+++ b/tests/gdimagecopymergegray/gdimagecopymergegray.c
@@ -0,0 +1,38 @@
+/**
+ * Basic test for gdImageCopyMergeGray()
+ */
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr dst = NULL;
+	gdImagePtr src = NULL;
+	int error = 0;
+
+	dst = gdImageCreate(100, 100);
+	src = gdImageCreate(50, 50);
+
+	if (gdTestAssert(!dst)) {
+		error = 1;
+		goto done;
+	}
+	if (gdTestAssert(!src)) {
+		error = 1;
+		goto done;
+	}
+
+	gdImageColorAllocate(src, 255, 255, 255);
+	gdImageColorAllocate(dst, 0, 0, 0);
+	gdImageCopyMergeGray(dst, src, 25, 25, 0, 0, 50, 50, 50);
+
+	if (!gdAssertImageEqualsToFile("gdimagecopymergegray/gdimagecopymergegray_exp.png", dst)) {
+		error = 1;
+	}
+
+done:
+	gdImageDestroy(dst);
+	gdImageDestroy(src);
+
+	return error;
+}
diff --git a/tests/gdimagecopymergegray/gdimagecopymergegray_exp.png b/tests/gdimagecopymergegray/gdimagecopymergegray_exp.png
new file mode 100644
index 0000000..1830281
--- /dev/null
+++ b/tests/gdimagecopymergegray/gdimagecopymergegray_exp.png
diff --git a/tests/gdimagecopyresampled/CMakeLists.txt b/tests/gdimagecopyresampled/CMakeLists.txt
index 636c811..00351ca 100644
--- a/tests/gdimagecopyresampled/CMakeLists.txt
+++ b/tests/gdimagecopyresampled/CMakeLists.txt
@@ -1,8 +1,12 @@
 LIST(APPEND TESTS_FILES
+	exact_alpha
+)
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
 	basic
 	basic_alpha
-	exact_alpha
 	bug00201
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagecopyresampled/Makemodule.am b/tests/gdimagecopyresampled/Makemodule.am
index 5d0d714..d42eab5 100644
--- a/tests/gdimagecopyresampled/Makemodule.am
+++ b/tests/gdimagecopyresampled/Makemodule.am
@@ -1,8 +1,10 @@
+libgd_test_programs += \
+	gdimagecopyresampled/exact_alpha
+
 if HAVE_LIBPNG
 libgd_test_programs += \
 	gdimagecopyresampled/basic \
 	gdimagecopyresampled/basic_alpha \
-	gdimagecopyresampled/exact_alpha \
 	gdimagecopyresampled/bug00201
 endif
 
diff --git a/tests/gdimagecopyresampled/bug00201.c b/tests/gdimagecopyresampled/bug00201.c
index 053b6db..0287267 100644
--- a/tests/gdimagecopyresampled/bug00201.c
+++ b/tests/gdimagecopyresampled/bug00201.c
@@ -48,23 +48,23 @@ int main()
     fp = gdTestFileOpen2("gdimagecopyresampled", "bug00201_src.png");
     logo_source = gdImageCreateFromPng(fp);
     fclose(fp);
-    
+
     logo = blank_image(SRC_WIDTH,SRC_HEIGHT);
     gdImageAlphaBlending(logo, 0);
     gdImageCopy(logo, logo_source, 0,0, 0,0, SRC_WIDTH,SRC_HEIGHT);
     gdImageDestroy(logo_source);
-    
+
     scaled_logo = blank_image(DEST_WIDTH,DEST_HEIGHT);
     gdImageAlphaBlending(scaled_logo, 0);
     gdImageCopyResampled(scaled_logo, logo, 0,0, 0,0, 200,105, SRC_WIDTH,SRC_HEIGHT);
     gdImageDestroy(logo);
-    
+
     layers[0] = background;
     layers[1] = scaled_logo;
     img = flatten(layers, 2, DEST_WIDTH, DEST_HEIGHT);
     gdImageDestroy(background);
     gdImageDestroy(scaled_logo);
-    
+
     gdAssertImageEqualsToFile("gdimagecopyresampled/bug00201_exp.png", img);
     gdImageDestroy(img);
     return gdNumFailures();
diff --git a/tests/gdimagecopyresized/.gitignore b/tests/gdimagecopyresized/.gitignore
new file mode 100644
index 0000000..185cf1f
--- /dev/null
+++ b/tests/gdimagecopyresized/.gitignore
@@ -0,0 +1 @@
+/gdimagecopyresized
diff --git a/tests/gdimagecopyresized/CMakeLists.txt b/tests/gdimagecopyresized/CMakeLists.txt
new file mode 100644
index 0000000..78b4fa9
--- /dev/null
+++ b/tests/gdimagecopyresized/CMakeLists.txt
@@ -0,0 +1,7 @@
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	gdimagecopyresized
+)
+ENDIF(PNG_FOUND)
+
+ADD_GD_TESTS()
diff --git a/tests/gdimagecopyresized/Makemodule.am b/tests/gdimagecopyresized/Makemodule.am
new file mode 100644
index 0000000..9d83e40
--- /dev/null
+++ b/tests/gdimagecopyresized/Makemodule.am
@@ -0,0 +1,8 @@
+if HAVE_LIBPNG
+libgd_test_programs += \
+	gdimagecopyresized/gdimagecopyresized
+endif
+
+EXTRA_DIST += \
+	gdimagecopyresized/CMakeLists.txt \
+	gdimagecopyresized/gdimagecopyresized_exp.png
diff --git a/tests/gdimagecopyresized/gdimagecopyresized.c b/tests/gdimagecopyresized/gdimagecopyresized.c
new file mode 100644
index 0000000..137f84b
--- /dev/null
+++ b/tests/gdimagecopyresized/gdimagecopyresized.c
@@ -0,0 +1,35 @@
+/**
+ * add test case for gdImageCopyResized
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr src;
+	gdImagePtr dst;
+	gdImagePtr dst_tc;
+
+	/* We prepare two image type: Palette and True Color */
+	/* src image is white, while dst and dst_tc is black */
+	src = gdImageCreate(64, 64);
+	gdImageColorAllocate(src, 255, 255, 255);
+	dst = gdImageCreate(128, 128);
+	gdImageColorAllocate(dst, 0, 0, 0);
+	dst_tc = gdImageCreateTrueColor(128, 128);
+
+	/* Copy src to two image type separately */
+	/* We copy src to the center of dst and dst_tc */
+	gdImageCopyResized(dst, src, 32, 32, 0, 0, 64, 64, 64, 64);
+	gdImageCopyResized(dst_tc, src, 32, 32, 0, 0, 64, 64, 64, 64);
+
+	gdAssertImageEqualsToFile("gdimagecopyresized/gdimagecopyresized_exp.png", dst);
+	gdAssertImageEqualsToFile("gdimagecopyresized/gdimagecopyresized_exp.png", dst_tc);
+
+	gdImageDestroy(src);
+	gdImageDestroy(dst);
+	gdImageDestroy(dst_tc);
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimagecopyresized/gdimagecopyresized_exp.png b/tests/gdimagecopyresized/gdimagecopyresized_exp.png
new file mode 100644
index 0000000..32fa084
--- /dev/null
+++ b/tests/gdimagecopyresized/gdimagecopyresized_exp.png
diff --git a/tests/gdimagecopyrotated/CMakeLists.txt b/tests/gdimagecopyrotated/CMakeLists.txt
index fc17e9d..7f1a678 100644
--- a/tests/gdimagecopyrotated/CMakeLists.txt
+++ b/tests/gdimagecopyrotated/CMakeLists.txt
@@ -1,5 +1,7 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	bug00020
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagecreate/.gitignore b/tests/gdimagecreate/.gitignore
new file mode 100644
index 0000000..6300aed
--- /dev/null
+++ b/tests/gdimagecreate/.gitignore
@@ -0,0 +1 @@
+/bug00340
diff --git a/tests/gdimagecreate/CMakeLists.txt b/tests/gdimagecreate/CMakeLists.txt
new file mode 100644
index 0000000..1cd0c1a
--- /dev/null
+++ b/tests/gdimagecreate/CMakeLists.txt
@@ -0,0 +1,5 @@
+LIST(APPEND TESTS_FILES
+	bug00340
+)
+
+ADD_GD_TESTS()
diff --git a/tests/gdimagecreate/Makemodule.am b/tests/gdimagecreate/Makemodule.am
new file mode 100644
index 0000000..8866086
--- /dev/null
+++ b/tests/gdimagecreate/Makemodule.am
@@ -0,0 +1,5 @@
+libgd_test_programs += \
+	gdimagecreate/bug00340
+
+EXTRA_DIST += \
+	gdimagecreate/CMakeLists.txt
diff --git a/tests/gdimagecreate/bug00340.c b/tests/gdimagecreate/bug00340.c
new file mode 100644
index 0000000..9c6eff3
--- /dev/null
+++ b/tests/gdimagecreate/bug00340.c
@@ -0,0 +1,29 @@
+/**
+ * Regression test for <https://github.com/libgd/libgd/issues/340>
+ *
+ * We're testing that trying to create an oversized image fails early,
+ * triggering an appropriate warning.
+ */
+
+#include <string.h>
+#include "gd.h"
+#include "gd_errors.h"
+#include "gdtest.h"
+
+#define MSG "product of memory allocation multiplication would exceed INT_MAX, failing operation gracefully\n"
+
+void error_handler(int priority, const char *format, ...)
+{
+	gdTestAssert(priority == GD_WARNING);
+	gdTestAssert(!strcmp(format, MSG));
+}
+
+int main()
+{
+	gdImagePtr im;
+
+	im = gdImageCreate(64970, 65111);
+	gdTestAssert(im == NULL);
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimagecrop/.gitignore b/tests/gdimagecrop/.gitignore
index a90ef00..ada3cad 100644
--- a/tests/gdimagecrop/.gitignore
+++ b/tests/gdimagecrop/.gitignore
@@ -1,2 +1,6 @@
 /bug00297
+/bug00432
+/bug00485_auto
+/bug00485_threshold
+/bug00486
 /php_bug_72494
diff --git a/tests/gdimagecrop/CMakeLists.txt b/tests/gdimagecrop/CMakeLists.txt
index 4b1e97e..43f6f6c 100644
--- a/tests/gdimagecrop/CMakeLists.txt
+++ b/tests/gdimagecrop/CMakeLists.txt
@@ -1,6 +1,10 @@
-SET(TESTS_FILES
+LIST(APPEND TESTS_FILES
 	bug00297
+	bug00432
+	bug00485_auto
+	bug00485_threshold
 	php_bug_72494
+	bug00486
 )
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagecrop/Makemodule.am b/tests/gdimagecrop/Makemodule.am
index fe73c1d..1725f6c 100644
--- a/tests/gdimagecrop/Makemodule.am
+++ b/tests/gdimagecrop/Makemodule.am
@@ -1,5 +1,9 @@
 libgd_test_programs += \
 	gdimagecrop/bug00297 \
+	gdimagecrop/bug00432 \
+	gdimagecrop/bug00485_auto \
+	gdimagecrop/bug00485_threshold \
+	gdimagecrop/bug00486 \
 	gdimagecrop/php_bug_72494
 
 EXTRA_DIST += \
diff --git a/tests/gdimagecrop/bug00432.c b/tests/gdimagecrop/bug00432.c
new file mode 100644
index 0000000..d3f681f
--- /dev/null
+++ b/tests/gdimagecrop/bug00432.c
@@ -0,0 +1,45 @@
+/**
+ * Test that gdImageCrop() retains transparency
+ *
+ * We create an image with transparent pixels, crop the image, and check whether
+ * all pixels are identical to the respective source image.
+ *
+ * See <https://github.com/libgd/libgd/issues/432>
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+#define WIDTH 10
+#define HEIGHT 10
+#define XOFF 1
+#define YOFF 1
+
+
+int main()
+{
+    gdImagePtr src, dst;
+    gdRect crop = {XOFF, YOFF, WIDTH-XOFF-1, HEIGHT-YOFF-1};
+    int i, j;
+
+    src = gdImageCreateTrueColor(WIDTH, HEIGHT);
+    gdImageAlphaBlending(src, gdEffectReplace);
+    gdImageFilledRectangle(src, 0, 0, WIDTH-1, HEIGHT-1,
+            gdTrueColorAlpha(gdRedMax, gdGreenMax, gdBlueMax, gdAlphaMax));
+
+    dst = gdImageCrop(src, &crop);
+    gdTestAssert(dst != NULL);
+
+    for (i = 0; i < gdImageSX(dst); i++) {
+        for (j = 0; j < gdImageSY(dst); j++) {
+            gdTestAssert(gdImageGetPixel(dst, i, j) == gdImageGetPixel(src, i+XOFF, j+YOFF));
+        }
+    }
+
+    gdImageDestroy(src);
+    gdImageDestroy(dst);
+
+    return gdNumFailures();
+}
diff --git a/tests/gdimagecrop/bug00485_auto.c b/tests/gdimagecrop/bug00485_auto.c
new file mode 100644
index 0000000..3c0627e
--- /dev/null
+++ b/tests/gdimagecrop/bug00485_auto.c
@@ -0,0 +1,52 @@
+/**
+ * Test that gdImageCropAuto() works pixel precise
+ *
+ * We test that a single black pixel anywhere (but the corners) on an 8x8 pixel
+ * image with a white background is auto-cropped to a 1x1 pixel image with a
+ * black pixel.
+ *
+ * See <https://github.com/libgd/libgd/issues/485>
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+gdImagePtr createWhiteImageWithBlackPixelAt(int x, int y)
+{
+    gdImagePtr im = gdImageCreateTrueColor(8, 8);
+    gdImageFilledRectangle(im, 0, 0, 7, 7, 0xffffff);
+    gdImageSetPixel(im, x, y, 0x000000);
+    return im;
+}
+
+
+int main()
+{
+    int x, y, height, width, color;
+    gdImagePtr orig, cropped;
+
+    for (y = 0; y < 8; y++) {
+        for (x = 0; x < 8; x++) {
+            if ((x == 0 && (y == 0 || y == 7)) || (x == 7 && (y == 0 || y == 7))) {
+                continue; // skip the corners
+            }
+            orig = createWhiteImageWithBlackPixelAt(x, y);
+            cropped = gdImageCropAuto(orig, GD_CROP_SIDES);
+            gdTestAssertMsg(cropped != NULL, "Pixel at %d, %d: unexpected NULL crop\n", x, y);
+            if (cropped) {
+                width = gdImageSX(cropped);
+                gdTestAssertMsg(width == 1, "Pixel at %d, %d: unexpected width (%d)\n", x, y, width);
+                height = gdImageSY(cropped);
+                gdTestAssertMsg(height == 1, "Pixel at %d, %d: unexpected height (%d)\n", x, y, height);
+                color = gdImageGetPixel(cropped, 0, 0);
+                gdTestAssertMsg(color == 0x000000, "Pixel at %d, %d: unexpected color (%d)\n", x, y, color);
+                gdImageDestroy(cropped);
+            }
+            gdImageDestroy(orig);
+        }
+    }
+
+    return gdNumFailures();
+}
diff --git a/tests/gdimagecrop/bug00485_threshold.c b/tests/gdimagecrop/bug00485_threshold.c
new file mode 100644
index 0000000..31ac38f
--- /dev/null
+++ b/tests/gdimagecrop/bug00485_threshold.c
@@ -0,0 +1,48 @@
+/**
+ * Test that gdImageCropThreshold() works pixel precise
+ *
+ * We test that a single black pixel anywhere on an 8x8 pixel image with a white
+ * background is threshold-cropped to a 1x1 pixel image with a black pixel.
+ *
+ * See <https://github.com/libgd/libgd/issues/485>
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+gdImagePtr createWhiteImageWithBlackPixelAt(int x, int y)
+{
+    gdImagePtr im = gdImageCreateTrueColor(8, 8);
+    gdImageFilledRectangle(im, 0, 0, 7, 7, 0xffffff);
+    gdImageSetPixel(im, x, y, 0x000000);
+    return im;
+}
+
+
+int main()
+{
+    int x, y, height, width, color;
+    gdImagePtr orig, cropped;
+
+    for (y = 0; y < 8; y++) {
+        for (x = 0; x < 8; x++) {
+            orig = createWhiteImageWithBlackPixelAt(x, y);
+            cropped = gdImageCropThreshold(orig, 0xffffff, 1.0);
+            gdTestAssertMsg(cropped != NULL, "Pixel at %d, %d: unexpected NULL crop\n", x, y);
+            if (cropped) {
+                width = gdImageSX(cropped);
+                gdTestAssertMsg(width == 1, "Pixel at %d, %d: unexpected width (%d)\n", x, y, width);
+                height = gdImageSY(cropped);
+                gdTestAssertMsg(height == 1, "Pixel at %d, %d: unexpected height (%d)\n", x, y, height);
+                color = gdImageGetPixel(cropped, 0, 0);
+                gdTestAssertMsg(color == 0x000000, "Pixel at %d, %d: unexpected color (%d)\n", x, y, color);
+                gdImageDestroy(cropped);
+            }
+            gdImageDestroy(orig);
+        }
+    }
+
+    return gdNumFailures();
+}
diff --git a/tests/gdimagecrop/bug00486.c b/tests/gdimagecrop/bug00486.c
new file mode 100644
index 0000000..289d88f
--- /dev/null
+++ b/tests/gdimagecrop/bug00486.c
@@ -0,0 +1,48 @@
+/**
+ * Test that gdImageCropAuto() crops left and right as well
+ *
+ * We test that an image with four unicolored quadrants, where either both left
+ * quadrants or both right quadrants have the same color, but the remaining
+ * quadrants have different colors, are treated identically by
+ * gdImageCropAuto(…, GD_CROP_SIDES).
+ *
+ * See <https://github.com/libgd/libgd/issues/486>
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+    gdImagePtr orig, croppedLeft, croppedRight;
+    int red, green, blue;
+
+    orig = gdImageCreateTrueColor(8, 8);
+    red = gdImageColorAllocate(orig, 255, 0, 0);
+    green = gdImageColorAllocate(orig, 0, 255, 0);
+    blue = gdImageColorAllocate(orig, 0, 0, 255);
+
+    gdImageFilledRectangle(orig, 0, 0, 3, 3, green); // tl
+    gdImageFilledRectangle(orig, 4, 0, 7, 3, red);   // tr
+    gdImageFilledRectangle(orig, 0, 4, 3, 7, green); // bl
+    gdImageFilledRectangle(orig, 4, 4, 7, 7, blue);  // br
+    croppedLeft = gdImageCropAuto(orig, GD_CROP_SIDES);
+    gdTestAssert(croppedLeft != NULL);
+
+    gdImageFilledRectangle(orig, 0, 0, 3, 3, red);   // tl
+    gdImageFilledRectangle(orig, 4, 0, 7, 3, green); // tr
+    gdImageFilledRectangle(orig, 0, 4, 3, 7, blue);  // bl
+    gdImageFilledRectangle(orig, 4, 4, 7, 7, green); // br
+    croppedRight = gdImageCropAuto(orig, GD_CROP_SIDES);
+    gdTestAssert(croppedRight != NULL);
+
+    gdAssertImageEquals(croppedRight, croppedLeft);
+
+	gdImageDestroy(orig);
+	gdImageDestroy(croppedLeft);
+	gdImageDestroy(croppedRight);
+
+    return gdNumFailures();
+}
diff --git a/tests/gdimageellipse/.gitignore b/tests/gdimageellipse/.gitignore
new file mode 100644
index 0000000..58e31a6
--- /dev/null
+++ b/tests/gdimageellipse/.gitignore
@@ -0,0 +1 @@
+/bug00169
diff --git a/tests/gdimageellipse/CMakeLists.txt b/tests/gdimageellipse/CMakeLists.txt
new file mode 100644
index 0000000..b7d79f2
--- /dev/null
+++ b/tests/gdimageellipse/CMakeLists.txt
@@ -0,0 +1,7 @@
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	bug00169
+)
+ENDIF(PNG_FOUND)
+
+ADD_GD_TESTS()
diff --git a/tests/gdimageellipse/Makemodule.am b/tests/gdimageellipse/Makemodule.am
new file mode 100644
index 0000000..11d2079
--- /dev/null
+++ b/tests/gdimageellipse/Makemodule.am
@@ -0,0 +1,8 @@
+if HAVE_LIBPNG
+libgd_test_programs += \
+	gdimageellipse/bug00169
+endif
+
+EXTRA_DIST += \
+	gdimageellipse/CMakeLists.txt \
+	gdimageellipse/bug00169_exp.png
diff --git a/tests/gdimageellipse/bug00169.c b/tests/gdimageellipse/bug00169.c
new file mode 100644
index 0000000..8246c8c
--- /dev/null
+++ b/tests/gdimageellipse/bug00169.c
@@ -0,0 +1,22 @@
+/**
+ * add test case for gdImageEllipse
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	int white = 0;
+
+	im = gdImageCreateTrueColor(2200, 2200);
+	white = gdImageColorAllocate(im, 255, 255, 255);
+
+	gdImageEllipse(im, 1100, 1100, 2200, 2200, white);
+	gdAssertImageEqualsToFile("gdimageellipse/bug00169_exp.png", im);
+
+	gdImageDestroy(im);
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimageellipse/bug00169_exp.png b/tests/gdimageellipse/bug00169_exp.png
new file mode 100644
index 0000000..f844608
--- /dev/null
+++ b/tests/gdimageellipse/bug00169_exp.png
diff --git a/tests/gdimagefile/CMakeLists.txt b/tests/gdimagefile/CMakeLists.txt
index 55ae374..8676264 100644
--- a/tests/gdimagefile/CMakeLists.txt
+++ b/tests/gdimagefile/CMakeLists.txt
@@ -1,5 +1,11 @@
+IF(TIFF_FOUND)
+IF(WEBP_FOUND)
+IF(ENABLE_GD_FORMATS)
 LIST(APPEND TESTS_FILES
 	gdnametest
 )
+ENDIF(ENABLE_GD_FORMATS)
+ENDIF(WEBP_FOUND)
+ENDIF(TIFF_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagefile/Makemodule.am b/tests/gdimagefile/Makemodule.am
index b537cbc..8c9e4d5 100644
--- a/tests/gdimagefile/Makemodule.am
+++ b/tests/gdimagefile/Makemodule.am
@@ -1,5 +1,11 @@
+if HAVE_LIBTIFF
+if HAVE_LIBWEBP
+if ENABLE_GD_FORMATS
 libgd_test_programs += \
 	gdimagefile/gdnametest
+endif
+endif
+endif
 
 EXTRA_DIST += \
 	gdimagefile/CMakeLists.txt \
diff --git a/tests/gdimagefile/gdnametest.c b/tests/gdimagefile/gdnametest.c
index 66da484..fcd040a 100644
--- a/tests/gdimagefile/gdnametest.c
+++ b/tests/gdimagefile/gdnametest.c
@@ -11,150 +11,145 @@
 #define LY (HEIGHT/2)   // Line Y
 #define HT 2            // Half of line-thickness
 
-
-gdImagePtr mkwhite(int x, int y)
+static gdImagePtr
+mkwhite(int x, int y)
 {
-    gdImagePtr im;
+	gdImagePtr im;
 
 	im = gdImageCreateTrueColor(x, y);
 	gdImageFilledRectangle(im, 0, 0, x-1, y-1,
-                           gdImageColorExactAlpha(im, 255, 255, 255, 0));
+	                       gdImageColorExactAlpha(im, 255, 255, 255, 0));
 
-    gdTestAssert(im != NULL);
+	gdTestAssert(im != NULL);
 
-    gdImageSetInterpolationMethod(im, GD_BICUBIC);    // FP interp'n
+	gdImageSetInterpolationMethod(im, GD_BICUBIC);    // FP interp'n
 
-    return im;
+	return im;
 }/* mkwhite*/
 
+static gdImagePtr
+mkcross(void)
+{
+	gdImagePtr im;
+	int fg, n;
 
-gdImagePtr mkcross() {
-    gdImagePtr im;
-    int fg, n;
-
-    im = mkwhite(WIDTH, HEIGHT);
-    fg = gdImageColorAllocate(im, 0, 0, 0);
+	im = mkwhite(WIDTH, HEIGHT);
+	fg = gdImageColorAllocate(im, 0, 0, 0);
 
-    for (n = -HT; n < HT; n++) {
-        gdImageLine(im, LX-n, 0, LX-n, HEIGHT-1, fg);
-        gdImageLine(im, 0, LY-n, WIDTH-1, LY-n, fg);
-    }/* for */
+	for (n = -HT; n < HT; n++) {
+		gdImageLine(im, LX-n, 0, LX-n, HEIGHT-1, fg);
+		gdImageLine(im, 0, LY-n, WIDTH-1, LY-n, fg);
+	}/* for */
 
-    return im;
+	return im;
 }/* mkcross*/
 
-
-
-
-void
-do_test() {
-
-    gdTestAssertMsg(strchr("123",'2') != 0, "strchr() is not functional.\n");
-    gdTestAssertMsg(strcasecmp("123abC","123Abc") == 0, "strcasecmp() is not functional.\n");
-    
-    int n;
-    struct {
-        const char *nm;     // Filename
-        unsigned maxdiff;   // Maximum total pixel diff
-        int required;       // 1 -> image type always supported, -1 -> skip it
-        int readonly;       // 1 -> gd can only read this type
-    } names[] = {
-        {"img.png",     0,  0,  0},
-        {"img.gif",     5,  1,  0},     // This seems to come from tc<->palette
-        {"img.GIF",     5,  1,  0},     // Test for case insensitivity
-        {"img.gd",      0,  1,  0}, 
-        {"img.gd2",     0,  0,  0}, 
-        {"img.jpg",    25,  0,  0},
-        {"img.jpeg",   25,  0,  0},
-        {"img.wbmp",    0,  1,  0},
-        {"img.bmp",     0,  1,  0},
-        {"img-ref.xpm", 0,  0,  1},
-        
-        // These break the test so I'm skipping them since the point
-        // of this test is not those loaders.
-        {"img-ref.xbm", 0, -1,  1},
-        {"img-ref.tga", 0, -1,  1},
-        {"img.webp",    0, -1,  0},
-        {"img.tiff",    0, -1,  0},
-
-        {NULL, 0}
-    };
-
-    for (n = 0; names[n].nm; n++) {
-        gdImagePtr orig, copy;
-        int status;
-        char *full_filename = NULL;
-
-        /* Some image readers are buggy and crash the program so we
-         * skip them.  Bug fixers should remove these from the list of
-         * skipped items as bugs are fixed. */
-        if (names[n].required < 0) {
-            printf("Skipping test for '%s'.  FIX THIS!\n", names[n].nm);
-            continue;
-        }/* if */
-
-        /* Skip this file if the current library build doesn't support
-         * it.  (If it's one of the built-in types, *that* a different
-         * problem; we assert that here.) */
-        if (!gdSupportsFileType(names[n].nm, 0)) {
-            gdTestAssertMsg(!names[n].required, "GD doesn't support required file type: %s\n", full_filename);
-            continue;
-        }/* if */
-
-        orig = mkcross();
-
-        /* Write the image unless writing is not supported. */
-        if (!names[n].readonly) {
-            /* Prepend the test directory; this is expected to be run in
-             * the parent dir. */
-            full_filename = gdTestTempFile(names[n].nm);
-            status = gdImageFile(orig, full_filename);
-            gdTestAssertMsg(status == GD_TRUE, "Failed to create %s\n", full_filename);
-        } else {
-            /* Prepend the test directory; this is expected to be run in
-             * the parent dir. */
-            full_filename = gdTestFilePath2("gdimagefile", names[n].nm);
-        }/* if */
-
-        copy = gdImageCreateFromFile(full_filename);
-        gdTestAssertMsg(!!copy, "Failed to load %s\n", full_filename);
-        if (!copy) continue;
-
-        gdTestAssertMsg(gdMaxPixelDiff(orig, copy) <= names[n].maxdiff,"Pixels different on %s\n", full_filename, full_filename);
-
-        if (!names[n].readonly) {
-            status = remove(full_filename);
-            gdTestAssertMsg(status == 0, "Failed to delete %s\n", full_filename);
-        }/* if */
-
-        free(full_filename);
-        gdImageDestroy(orig);
-        gdImageDestroy(copy);
-    }/* for */
+static void
+do_test(void)
+{
+	gdTestAssertMsg(strchr("123",'2') != 0, "strchr() is not functional.\n");
+	gdTestAssertMsg(strcasecmp("123abC","123Abc") == 0, "strcasecmp() is not functional.\n");
+
+	int n;
+	struct {
+		const char *nm;     // Filename
+		unsigned maxdiff;   // Maximum total pixel diff
+		int required;       // 1 -> image type always supported, -1 -> skip it
+		int readonly;       // 1 -> gd can only read this type
+	} names[] = {
+		{"img.png",     0,  0,  0},
+		{"img.gif",     5,  1,  0},     // This seems to come from tc<->palette
+		{"img.GIF",     5,  1,  0},     // Test for case insensitivity
+		{"img.gd",      0,  1,  0},
+		{"img.gd2",     0,  0,  0},
+		{"img.jpg",    25,  0,  0},
+		{"img.jpeg",   25,  0,  0},
+		{"img.wbmp",    0,  1,  0},
+		{"img.bmp",     0,  1,  0},
+		{"img-ref.xpm", 0,  0,  1},
+		{"img-ref.xbm", 0,  1,  1},
+		{"img-ref.tga", 0,  1,  1},
+		{"img.webp",   10,  1,  0},
+		{"img.tiff",    0,  1,  0},
+
+		{NULL, 0}
+	};
+
+	for (n = 0; names[n].nm; n++) {
+		gdImagePtr orig, copy;
+		int status;
+		char *full_filename = NULL;
+		unsigned int pixels;
+
+		/* Some image readers are buggy and crash the program so we
+		 * skip them.  Bug fixers should remove these from the list of
+		 * skipped items as bugs are fixed. */
+		if (names[n].required < 0) {
+			printf("Skipping test for '%s'.  FIX THIS!\n", names[n].nm);
+			continue;
+		}/* if */
+
+		/* Skip this file if the current library build doesn't support
+		 * it.  (If it's one of the built-in types, *that* a different
+		 * problem; we assert that here.) */
+		if (!gdSupportsFileType(names[n].nm, 0)) {
+			gdTestAssertMsg(!names[n].required, "GD doesn't support required file type: %s\n", names[n].nm);
+			continue;
+		}/* if */
+
+		orig = mkcross();
+
+		/* Write the image unless writing is not supported. */
+		if (!names[n].readonly) {
+			/* Prepend the test directory; this is expected to be run in
+			 * the parent dir. */
+			full_filename = gdTestTempFile(names[n].nm);
+			status = gdImageFile(orig, full_filename);
+			gdTestAssertMsg(status == GD_TRUE, "Failed to create %s\n", full_filename);
+		} else {
+			/* Prepend the test directory; this is expected to be run in
+			 * the parent dir. */
+			full_filename = gdTestFilePath2("gdimagefile", names[n].nm);
+		}/* if */
+
+		copy = gdImageCreateFromFile(full_filename);
+		gdTestAssertMsg(!!copy, "Failed to load %s\n", full_filename);
+		if (!copy) continue;
+
+		pixels = gdMaxPixelDiff(orig, copy);
+		gdTestAssertMsg(pixels <= names[n].maxdiff, "%u pixels different on %s\n", pixels, full_filename);
+
+		if (!names[n].readonly) {
+			status = remove(full_filename);
+			gdTestAssertMsg(status == 0, "Failed to delete %s\n", full_filename);
+		}/* if */
+
+		free(full_filename);
+		gdImageDestroy(orig);
+		gdImageDestroy(copy);
+	}/* for */
 
 }/* do_test*/
 
+static void
+do_errortest(void)
+{
+	gdImagePtr im;
 
-void
-do_errortest() {
-    gdImagePtr im;
-
-    im = mkcross();
+	im = mkcross();
 
-    gdTestAssert(!gdImageFile(im, "img.xpng"));
-    gdTestAssert(!gdImageFile(im, "bobo"));
-    gdTestAssert(!gdImageFile(im, "png"));
-    gdTestAssert(!gdImageFile(im, ""));
+	gdTestAssert(!gdImageFile(im, "img.xpng"));
+	gdTestAssert(!gdImageFile(im, "bobo"));
+	gdTestAssert(!gdImageFile(im, "png"));
+	gdTestAssert(!gdImageFile(im, ""));
 
-    gdImageDestroy(im);
+	gdImageDestroy(im);
 }/* do_errortest*/
 
-
 int main()
 {
+	do_test();
+	do_errortest();
 
-    do_test();
-    do_errortest();
-
-    return gdNumFailures();
+	return gdNumFailures();
 }
diff --git a/tests/gdimagefill/CMakeLists.txt b/tests/gdimagefill/CMakeLists.txt
index c54281e..457fd8d 100644
--- a/tests/gdimagefill/CMakeLists.txt
+++ b/tests/gdimagefill/CMakeLists.txt
@@ -1,3 +1,4 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	bug00002_1
 	bug00002_2
@@ -5,5 +6,6 @@ LIST(APPEND TESTS_FILES
 	bug00002_4
 	bug00104_1
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagefill/bug00002_1.c b/tests/gdimagefill/bug00002_1.c
index 752178a..3feaf42 100644
--- a/tests/gdimagefill/bug00002_1.c
+++ b/tests/gdimagefill/bug00002_1.c
@@ -37,4 +37,3 @@ int main()
 
 	return error;
 }
-
diff --git a/tests/gdimagefill/bug00002_2.c b/tests/gdimagefill/bug00002_2.c
index 982ae8f..4edcd6a 100644
--- a/tests/gdimagefill/bug00002_2.c
+++ b/tests/gdimagefill/bug00002_2.c
@@ -46,4 +46,3 @@ int main()
 	gdImageDestroy(tile);
 	return error;
 }
-
diff --git a/tests/gdimagefill/bug00002_3.c b/tests/gdimagefill/bug00002_3.c
index b11fbc9..1a1929e 100644
--- a/tests/gdimagefill/bug00002_3.c
+++ b/tests/gdimagefill/bug00002_3.c
@@ -51,4 +51,3 @@ int main()
 	gdImageDestroy(tile);
 	return error;
 }
-
diff --git a/tests/gdimagefill/bug00104_1.c b/tests/gdimagefill/bug00104_1.c
index 13247ca..694788a 100644
--- a/tests/gdimagefill/bug00104_1.c
+++ b/tests/gdimagefill/bug00104_1.c
@@ -8,26 +8,26 @@ int main()
 	gdImagePtr im, tile;
 	int tile_red, tile_blue;
 	int error = 0;
-	
+
 	im = gdImageCreate(200, 150);
 
 	tile = gdImageCreateTrueColor(2, 2);
-	
+
 	tile_red = gdImageColorAllocate(tile, 255, 0, 0);
 	tile_blue = gdImageColorAllocate(tile, 0, 0, 255);
-	
+
 	gdImageSetPixel(tile, 0, 0, tile_red);
 	gdImageSetPixel(tile, 1, 1, tile_red);
 	gdImageSetPixel(tile, 1, 0, tile_blue);
 	gdImageSetPixel(tile, 0, 1, tile_blue);
-	
+
 	gdImageSetTile(im, tile);
 	gdImageFill(im, 11, 12, gdTiled);
 
 	if (!gdAssertImageEqualsToFile("gdimagefill/bug00104_1_exp.png", im)) {
 		error = 1;
 	}
-	
+
 	gdImageDestroy(im);
 	gdImageDestroy(tile);
 	return error;
diff --git a/tests/gdimagefilledarc/.gitignore b/tests/gdimagefilledarc/.gitignore
index e6d2cbe..da4b002 100644
--- a/tests/gdimagefilledarc/.gitignore
+++ b/tests/gdimagefilledarc/.gitignore
@@ -1 +1,2 @@
+/bug00351
 /php_bug43828
diff --git a/tests/gdimagefilledarc/CMakeLists.txt b/tests/gdimagefilledarc/CMakeLists.txt
index 1a0a204..4042df9 100644
--- a/tests/gdimagefilledarc/CMakeLists.txt
+++ b/tests/gdimagefilledarc/CMakeLists.txt
@@ -1,5 +1,8 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
+	bug00351
 	php_bug43828
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagefilledarc/Makemodule.am b/tests/gdimagefilledarc/Makemodule.am
index 4af6963..710c0a0 100644
--- a/tests/gdimagefilledarc/Makemodule.am
+++ b/tests/gdimagefilledarc/Makemodule.am
@@ -1,8 +1,10 @@
 if HAVE_LIBPNG
 libgd_test_programs += \
+	gdimagefilledarc/bug00351 \
 	gdimagefilledarc/php_bug43828
 endif
 
 EXTRA_DIST += \
 	gdimagefilledarc/CMakeLists.txt \
+	gdimagefilledarc/bug00351_exp.png \
 	gdimagefilledarc/php_bug43828_exp.png
diff --git a/tests/gdimagefilledarc/bug00351.c b/tests/gdimagefilledarc/bug00351.c
new file mode 100644
index 0000000..20b0fde
--- /dev/null
+++ b/tests/gdimagefilledarc/bug00351.c
@@ -0,0 +1,30 @@
+/**
+ * Test drawing of pies starting and/or ending near 90°
+ *
+ * See <https://github.com/libgd/libgd/issues/351>.
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+    gdImagePtr im;
+    int white, navy, red;
+
+    im = gdImageCreateTrueColor(500, 500);
+    white = gdTrueColorAlpha(0xFF, 0xFF, 0xFF, gdAlphaOpaque);
+    navy = gdTrueColorAlpha(0x00, 0x00, 0x80, gdAlphaOpaque);
+    red = gdTrueColorAlpha(0xFF, 0x00, 0x00, gdAlphaOpaque);
+
+    gdImageFilledArc(im, 250, 250, 500, 250, 0, 88, white, gdPie);
+    gdImageFilledArc(im, 250, 250, 500, 250, 88, 91 , navy, gdPie);
+    gdImageFilledArc(im, 250, 250, 500, 250, 91, 360 , red, gdPie);
+
+    gdAssertImageEqualsToFile("gdimagefilledarc/bug00351_exp.png", im);
+
+    gdImageDestroy(im);
+	return gdNumFailures();
+}
diff --git a/tests/gdimagefilledarc/bug00351_exp.png b/tests/gdimagefilledarc/bug00351_exp.png
new file mode 100644
index 0000000..16b2db2
--- /dev/null
+++ b/tests/gdimagefilledarc/bug00351_exp.png
diff --git a/tests/gdimagefilledellipse/.gitignore b/tests/gdimagefilledellipse/.gitignore
index e039565..9adfb75 100644
--- a/tests/gdimagefilledellipse/.gitignore
+++ b/tests/gdimagefilledellipse/.gitignore
@@ -1,3 +1,4 @@
 /bug00010
+/bug00169
 /bug00191
 /github_bug_00238
diff --git a/tests/gdimagefilledellipse/CMakeLists.txt b/tests/gdimagefilledellipse/CMakeLists.txt
index 63f34f2..48286e4 100644
--- a/tests/gdimagefilledellipse/CMakeLists.txt
+++ b/tests/gdimagefilledellipse/CMakeLists.txt
@@ -1,7 +1,10 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	bug00010
+	bug00169
 	bug00191
 	github_bug_00238
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagefilledellipse/Makemodule.am b/tests/gdimagefilledellipse/Makemodule.am
index 6a5185a..0a88686 100644
--- a/tests/gdimagefilledellipse/Makemodule.am
+++ b/tests/gdimagefilledellipse/Makemodule.am
@@ -1,6 +1,7 @@
 if HAVE_LIBPNG
 libgd_test_programs += \
 	gdimagefilledellipse/bug00010 \
+	gdimagefilledellipse/bug00169 \
 	gdimagefilledellipse/bug00191 \
 	gdimagefilledellipse/github_bug_00238
 endif
@@ -8,5 +9,6 @@ endif
 EXTRA_DIST += \
 	gdimagefilledellipse/CMakeLists.txt \
 	gdimagefilledellipse/bug00010_exp.png \
+	gdimagefilledellipse/bug00169_exp.png \
 	gdimagefilledellipse/bug00191.png \
 	gdimagefilledellipse/github_bug_00238_exp.png
diff --git a/tests/gdimagefilledellipse/bug00169.c b/tests/gdimagefilledellipse/bug00169.c
new file mode 100644
index 0000000..639e52f
--- /dev/null
+++ b/tests/gdimagefilledellipse/bug00169.c
@@ -0,0 +1,22 @@
+/**
+ * add test case for gdImageFilledEllipse
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	int white = 0;
+
+	im = gdImageCreateTrueColor(2200, 2200);
+	white = gdImageColorAllocate(im, 255, 255, 255);
+
+	gdImageFilledEllipse(im, 1100, 1100, 2200, 2200, white);
+	gdAssertImageEqualsToFile("gdimagefilledellipse/bug00169_exp.png", im);
+
+	gdImageDestroy(im);
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimagefilledellipse/bug00169_exp.png b/tests/gdimagefilledellipse/bug00169_exp.png
new file mode 100644
index 0000000..db88390
--- /dev/null
+++ b/tests/gdimagefilledellipse/bug00169_exp.png
diff --git a/tests/gdimagefilledellipse/github_bug_00238.c b/tests/gdimagefilledellipse/github_bug_00238.c
index 499923f..67c93fd 100644
--- a/tests/gdimagefilledellipse/github_bug_00238.c
+++ b/tests/gdimagefilledellipse/github_bug_00238.c
@@ -12,7 +12,7 @@ int main()
 		goto exit;
 	}
 
-	gdImageAlphaBlending(im, gdEffectNormal);	
+	gdImageAlphaBlending(im, gdEffectNormal);
 	gdImageFilledRectangle(im, 0, 0, 140, 199, gdTrueColorAlpha(0,0,0,127));
 
 	gdImageAlphaBlending(im, gdEffectAlphaBlend);
diff --git a/tests/gdimagefilledpolygon/CMakeLists.txt b/tests/gdimagefilledpolygon/CMakeLists.txt
index 97801e2..030a224 100644
--- a/tests/gdimagefilledpolygon/CMakeLists.txt
+++ b/tests/gdimagefilledpolygon/CMakeLists.txt
@@ -1,3 +1,4 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	gdimagefilledpolygon0
 	gdimagefilledpolygon1
@@ -7,5 +8,6 @@ LIST(APPEND TESTS_FILES
 	php_bug_64641
 	self_intersecting
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagefilledpolygon/self_intersecting.c b/tests/gdimagefilledpolygon/self_intersecting.c
index 6123cc1..f9b96da 100644
--- a/tests/gdimagefilledpolygon/self_intersecting.c
+++ b/tests/gdimagefilledpolygon/self_intersecting.c
@@ -1,31 +1,29 @@
-/**

- * We're testing the filling behavior of self-intersecting polygons, which is

- * *currently* using the even-odd fillrule.

- */

-

-

-#include "gd.h"

-#include "gdtest.h"

-

-

-int main()

-{

-    gdImagePtr im;

-    int black;

-    gdPoint points[] = {{50, 5}, {24, 86}, {93, 36}, {7, 36}, {76, 86}};

-    char *path;

-

-    im = gdImageCreate(100, 100);

-    gdImageColorAllocate(im, 255, 255, 255);

-    black = gdImageColorAllocate(im, 0, 0, 0);

-

-    gdImageFilledPolygon(im, points, 5, black);

-

-    path = gdTestFilePath2("gdimagefilledpolygon", "self_intersecting_exp.png");

-    gdAssertImageEqualsToFile(path, im);

-    gdFree(path);

-

-    gdImageDestroy(im);

-

-    return gdNumFailures();

-}

+/**
+ * We're testing the filling behavior of self-intersecting polygons, which is
+ * *currently* using the even-odd fillrule.
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	int black;
+	gdPoint points[] = {{50, 5}, {24, 86}, {93, 36}, {7, 36}, {76, 86}};
+	char *path;
+
+	im = gdImageCreate(100, 100);
+	gdImageColorAllocate(im, 255, 255, 255);
+	black = gdImageColorAllocate(im, 0, 0, 0);
+
+	gdImageFilledPolygon(im, points, 5, black);
+
+	path = gdTestFilePath2("gdimagefilledpolygon", "self_intersecting_exp.png");
+	gdAssertImageEqualsToFile(path, im);
+	gdFree(path);
+
+	gdImageDestroy(im);
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimagefilledrectangle/bug00004.c b/tests/gdimagefilledrectangle/bug00004.c
index 594e296..87e33dc 100644
--- a/tests/gdimagefilledrectangle/bug00004.c
+++ b/tests/gdimagefilledrectangle/bug00004.c
@@ -24,4 +24,3 @@ int main()
 		return 1;
 	}
 }
-
diff --git a/tests/gdimagefilledrectangle/bug00078.c b/tests/gdimagefilledrectangle/bug00078.c
index adf244e..4cde698 100644
--- a/tests/gdimagefilledrectangle/bug00078.c
+++ b/tests/gdimagefilledrectangle/bug00078.c
@@ -36,4 +36,3 @@ int main()
 	gdImageDestroy(im);
 	return 0;
 }
-
diff --git a/tests/gdimagefilledrectangle/bug00106_gdimagefilledrectangle.c b/tests/gdimagefilledrectangle/bug00106_gdimagefilledrectangle.c
index 24f5ceb..a6f5c06 100644
--- a/tests/gdimagefilledrectangle/bug00106_gdimagefilledrectangle.c
+++ b/tests/gdimagefilledrectangle/bug00106_gdimagefilledrectangle.c
@@ -24,4 +24,3 @@ int main()
 		return 1;
 	}
 }
-
diff --git a/tests/gdimagefilltoborder/Makemodule.am b/tests/gdimagefilltoborder/Makemodule.am
index fc7ed3d..779bda0 100644
--- a/tests/gdimagefilltoborder/Makemodule.am
+++ b/tests/gdimagefilltoborder/Makemodule.am
@@ -1,8 +1,6 @@
-if HAVE_LIBPNG
 libgd_test_programs += \
 	gdimagefilltoborder/bug00037 \
 	gdimagefilltoborder/github_bug_215
-endif
 
 EXTRA_DIST += \
 	gdimagefilltoborder/CMakeLists.txt
diff --git a/tests/gdimagefilltoborder/bug00037.c b/tests/gdimagefilltoborder/bug00037.c
index ab7e1b8..72e58b7 100644
--- a/tests/gdimagefilltoborder/bug00037.c
+++ b/tests/gdimagefilltoborder/bug00037.c
@@ -27,4 +27,3 @@ int main()
 	}
 
 }
-
diff --git a/tests/gdimagefilter/gdCopyBlurred.c b/tests/gdimagefilter/gdCopyBlurred.c
index dee2f1f..aec49f5 100644
--- a/tests/gdimagefilter/gdCopyBlurred.c
+++ b/tests/gdimagefilter/gdCopyBlurred.c
@@ -143,7 +143,7 @@ void do_crosstest()
 {
     gdImagePtr im = mkcross();
     gdImagePtr blurred;
-    const int RADIUS = 16; 
+    const int RADIUS = 16;
 
     gdTestAssert(!!im);
 
diff --git a/tests/gdimageflip/CMakeLists.txt b/tests/gdimageflip/CMakeLists.txt
index 39caf08..c532f01 100644
--- a/tests/gdimageflip/CMakeLists.txt
+++ b/tests/gdimageflip/CMakeLists.txt
@@ -1,5 +1,7 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	gdimageflip
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimageflip/gdimageflip.c b/tests/gdimageflip/gdimageflip.c
index a9dd187..da834ee 100644
--- a/tests/gdimageflip/gdimageflip.c
+++ b/tests/gdimageflip/gdimageflip.c
@@ -1,37 +1,34 @@
-/**

- * Testing the basic operation of the gdImageFlip*() functions

- */

-

-

-#include "gd.h"

-#include "gdtest.h"

-

-

-static void test_flip(void (*func)(gdImagePtr), const char *filename)

-{

-    gdImagePtr im;

-    FILE *fp;

-    char *path;

-

-    fp = gdTestFileOpen2("gdimageflip", "remi.png");

-    im = gdImageCreateFromPng(fp);

-    fclose(fp);

-

-    func(im);

-

-    path = gdTestFilePath2("gdimageflip", filename);

-    gdAssertImageEqualsToFile(path, im);

-    gdFree(path);

-

-    gdImageDestroy(im);

-}

-

-

-int main()

-{

-    test_flip(gdImageFlipVertical, "gdimageflipvertical_exp.png");

-    test_flip(gdImageFlipHorizontal, "gdimagefliphorizontal_exp.png");

-    test_flip(gdImageFlipBoth, "gdimageflipboth_exp.png");

-

-    return gdNumFailures();

-}

+/**
+ * Testing the basic operation of the gdImageFlip*() functions
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+static void test_flip(void (BGD_STDCALL *func)(gdImagePtr), const char *filename)
+{
+	gdImagePtr im;
+	FILE *fp;
+	char *path;
+
+	fp = gdTestFileOpen2("gdimageflip", "remi.png");
+	im = gdImageCreateFromPng(fp);
+	fclose(fp);
+
+	func(im);
+
+	path = gdTestFilePath2("gdimageflip", filename);
+	gdAssertImageEqualsToFile(path, im);
+	gdFree(path);
+
+	gdImageDestroy(im);
+}
+
+int main()
+{
+	test_flip(gdImageFlipVertical, "gdimageflipvertical_exp.png");
+	test_flip(gdImageFlipHorizontal, "gdimagefliphorizontal_exp.png");
+	test_flip(gdImageFlipBoth, "gdimageflipboth_exp.png");
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimagegrayscale/.gitignore b/tests/gdimagegrayscale/.gitignore
index 1ffd796..3e79ed7 100644
--- a/tests/gdimagegrayscale/.gitignore
+++ b/tests/gdimagegrayscale/.gitignore
@@ -1 +1,2 @@
 /basic
+/bug00386
diff --git a/tests/gdimagegrayscale/CMakeLists.txt b/tests/gdimagegrayscale/CMakeLists.txt
index 381c74d..b83521d 100644
--- a/tests/gdimagegrayscale/CMakeLists.txt
+++ b/tests/gdimagegrayscale/CMakeLists.txt
@@ -1,5 +1,8 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	basic
+	bug00386
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagegrayscale/Makemodule.am b/tests/gdimagegrayscale/Makemodule.am
index e715c5b..c6fec00 100644
--- a/tests/gdimagegrayscale/Makemodule.am
+++ b/tests/gdimagegrayscale/Makemodule.am
@@ -1,9 +1,11 @@
 if HAVE_LIBPNG
 libgd_test_programs += \
-	gdimagegrayscale/basic
+	gdimagegrayscale/basic \
+	gdimagegrayscale/bug00386
 endif
 
 EXTRA_DIST += \
 	gdimagegrayscale/CMakeLists.txt \
 	gdimagegrayscale/basic.png \
-	gdimagegrayscale/basic_exp.png
+	gdimagegrayscale/basic_exp.png \
+	gdimagegrayscale/bug00386.png
diff --git a/tests/gdimagegrayscale/basic.c b/tests/gdimagegrayscale/basic.c
index e3c21d8..3ecc482 100644
--- a/tests/gdimagegrayscale/basic.c
+++ b/tests/gdimagegrayscale/basic.c
@@ -1,29 +1,27 @@
-/**

- * Basic test for gdImageGrayScale()

- */

-

-

-#include "gd.h"

-#include "gdtest.h"

-

-

-int main()

-{

-    gdImagePtr im;

-    FILE *fp;

-    char *path;

-

-    fp = gdTestFileOpen2("gdimagegrayscale", "basic.png");

-    im = gdImageCreateFromPng(fp);

-    fclose(fp);

-

-    gdImageGrayScale(im);

-

-    path = gdTestFilePath2("gdimagegrayscale", "basic_exp.png");

-    gdAssertImageEqualsToFile(path, im);

-    gdFree(path);

-

-    gdImageDestroy(im);

-

-    return gdNumFailures();

-}

+/**
+ * Basic test for gdImageGrayScale()
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	FILE *fp;
+	char *path;
+
+	fp = gdTestFileOpen2("gdimagegrayscale", "basic.png");
+	im = gdImageCreateFromPng(fp);
+	fclose(fp);
+
+	gdImageGrayScale(im);
+
+	path = gdTestFilePath2("gdimagegrayscale", "basic_exp.png");
+	gdAssertImageEqualsToFile(path, im);
+	gdFree(path);
+
+	gdImageDestroy(im);
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimagegrayscale/bug00386.c b/tests/gdimagegrayscale/bug00386.c
new file mode 100644
index 0000000..2e68ed4
--- /dev/null
+++ b/tests/gdimagegrayscale/bug00386.c
@@ -0,0 +1,53 @@
+/**
+ * Test that gdImageGrayScale() produces pure gray-scale images
+ *
+ * We are reading a PNG image with transparency, apply gdImageGrayScale() and
+ * test that each pixel has equal red, blue and green components. To avoid
+ * flooding the test log, we bail out after the first non gray-scale pixel.
+ *
+ * We also make sure that the image is a truecolor image, since otherwise it is
+ * not guaranteed that all pixels are actually gray-scale.
+ *
+ * See also <https://github.com/libgd/libgd/issues/386>.
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+    gdImagePtr im;
+    FILE *fp;
+    int res;
+    int i, j;
+
+    fp = gdTestFileOpen2("gdimagegrayscale", "bug00386.png");
+    gdTestAssert(fp != NULL);
+    im = gdImageCreateFromPng(fp);
+    gdTestAssert(im != NULL);
+    fclose(fp);
+
+    res = gdImageTrueColor(im);
+    gdTestAssert(res != 0);
+
+    res = gdImageGrayScale(im);
+    gdTestAssert(res != 0);
+
+    for (i = 0; i < gdImageSX(im); i++) {
+        for (j = 0; j < gdImageSY(im); j++) {
+            int color = gdImageGetTrueColorPixel(im, i, j);
+            int red = gdImageRed(im, color);
+            int green = gdImageGreen(im, color);
+            int blue = gdImageBlue(im, color);
+            if (!gdTestAssert(red == green && green == blue)) {
+                return gdNumFailures();
+            }
+        }
+    }
+
+    gdImageDestroy(im);
+
+    return gdNumFailures();
+}
diff --git a/tests/gdimagegrayscale/bug00386.png b/tests/gdimagegrayscale/bug00386.png
new file mode 100644
index 0000000..b5d5d1f
--- /dev/null
+++ b/tests/gdimagegrayscale/bug00386.png
diff --git a/tests/gdimageline/CMakeLists.txt b/tests/gdimageline/CMakeLists.txt
index 8e1b524..c345ed1 100644
--- a/tests/gdimageline/CMakeLists.txt
+++ b/tests/gdimageline/CMakeLists.txt
@@ -1,12 +1,18 @@
 LIST(APPEND TESTS_FILES
-	gdimageline_aa
 	gdimageline_aa_outofrange
-	gdImageAALine_thickness
-	github_bug_167
+)
+
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
 	bug00077
 	bug00072
 	bug00111
 	bug00315
+	gdimageline_aa
+	gdimageline_bug5
+	gdImageAALine_thickness
+	github_bug_167
 )
+ENDIF(PNG_FOUND)
 
-ADD_GD_TESTS(m)
+ADD_GD_TESTS()
diff --git a/tests/gdimageline/bug00315.c b/tests/gdimageline/bug00315.c
index 7c94e41..719d155 100644
--- a/tests/gdimageline/bug00315.c
+++ b/tests/gdimageline/bug00315.c
@@ -1,39 +1,37 @@
-/**

- * Regression test for <https://github.com/libgd/libgd/issues/315>

- *

- * We're testing that a single-pointed gdImageAALine() is drawn as a single

- * non-antialized pixel, according to (two-pointed) vertical and horizontal

- * lines.

- */

-

-

-#include "gd.h"

-#include "gdtest.h"

-

-

-int main()

-{

-    gdImagePtr im;

-    int white, black;

-    char *path;

-

-    im = gdImageCreateTrueColor(6, 6);

-    white = gdImageColorAllocate(im, 255, 255, 255);

-    black = gdImageColorAllocate(im, 0, 0, 0);

-    gdImageFilledRectangle(im, 0,0, 5,5, white);

-

-    gdImageLine(im, 4,4, 4,4, black);

-    gdImageLine(im, 1,4, 2,4, black);

-    gdImageLine(im, 4,1, 4,2, black);

-

-	gdImageSetAntiAliased(im, black);

-    gdImageLine(im, 1,1, 1,1, gdAntiAliased);

-

-    path = gdTestFilePath2("gdimageline", "bug00315_exp.png");

-    gdAssertImageEqualsToFile(path, im);

-    gdFree(path);

-

-    gdImageDestroy(im);

-

-    return gdNumFailures();

-}

+/**
+ * Regression test for <https://github.com/libgd/libgd/issues/315>
+ *
+ * We're testing that a single-pointed gdImageAALine() is drawn as a single
+ * non-antialized pixel, according to (two-pointed) vertical and horizontal
+ * lines.
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	int white, black;
+	char *path;
+
+	im = gdImageCreateTrueColor(6, 6);
+	white = gdImageColorAllocate(im, 255, 255, 255);
+	black = gdImageColorAllocate(im, 0, 0, 0);
+	gdImageFilledRectangle(im, 0,0, 5,5, white);
+
+	gdImageLine(im, 4,4, 4,4, black);
+	gdImageLine(im, 1,4, 2,4, black);
+	gdImageLine(im, 4,1, 4,2, black);
+
+	gdImageSetAntiAliased(im, black);
+	gdImageLine(im, 1,1, 1,1, gdAntiAliased);
+
+	path = gdTestFilePath2("gdimageline", "bug00315_exp.png");
+	gdAssertImageEqualsToFile(path, im);
+	gdFree(path);
+
+	gdImageDestroy(im);
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimageline/gdimageline_bug5.c b/tests/gdimageline/gdimageline_bug5.c
index 44adc8e..d055b0c 100644
--- a/tests/gdimageline/gdimageline_bug5.c
+++ b/tests/gdimageline/gdimageline_bug5.c
@@ -10,7 +10,13 @@ int main() {
 	/* FILE *pngout; */
 	int black, white;
 
+	/* If the data seg size is less than 195000,
+	 * gdImageCrateTrueColor will return NULL.
+	 * See https://github.com/libgd/libgd/issues/621 */
 	im = gdImageCreateTrueColor(63318, 771);
+	if (gdTestAssertMsg(im != NULL, "gdImageCreateTrueColor() returns NULL\n") == 0) {
+		return gdNumFailures();
+	}
 
 	/* Allocate the color white (red, green and blue all maximum). */
 	white = gdImageColorAllocate(im, 255, 255, 255);
diff --git a/tests/gdimagenegate/CMakeLists.txt b/tests/gdimagenegate/CMakeLists.txt
index 381c74d..802c382 100644
--- a/tests/gdimagenegate/CMakeLists.txt
+++ b/tests/gdimagenegate/CMakeLists.txt
@@ -1,5 +1,7 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	basic
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagenegate/basic.c b/tests/gdimagenegate/basic.c
index b904eb8..563eec6 100644
--- a/tests/gdimagenegate/basic.c
+++ b/tests/gdimagenegate/basic.c
@@ -1,29 +1,27 @@
-/**

- * Basic test for gdImageNegate()

- */

-

-

-#include "gd.h"

-#include "gdtest.h"

-

-

-int main()

-{

-    gdImagePtr im;

-    FILE *fp;

-    char *path;

-

-    fp = gdTestFileOpen2("gdimagenegate", "basic.png");

-    im = gdImageCreateFromPng(fp);

-    fclose(fp);

-

-    gdImageNegate(im);

-

-    path = gdTestFilePath2("gdimagenegate", "basic_exp.png");

-    gdAssertImageEqualsToFile(path, im);

-    gdFree(path);

-

-    gdImageDestroy(im);

-

-    return gdNumFailures();

-}

+/**
+ * Basic test for gdImageNegate()
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	FILE *fp;
+	char *path;
+
+	fp = gdTestFileOpen2("gdimagenegate", "basic.png");
+	im = gdImageCreateFromPng(fp);
+	fclose(fp);
+
+	gdImageNegate(im);
+
+	path = gdTestFilePath2("gdimagenegate", "basic_exp.png");
+	gdAssertImageEqualsToFile(path, im);
+	gdFree(path);
+
+	gdImageDestroy(im);
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimageopenpolygon/CMakeLists.txt b/tests/gdimageopenpolygon/CMakeLists.txt
index 03c288d..5b3e069 100644
--- a/tests/gdimageopenpolygon/CMakeLists.txt
+++ b/tests/gdimageopenpolygon/CMakeLists.txt
@@ -1,8 +1,10 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	gdimageopenpolygon0
 	gdimageopenpolygon1
 	gdimageopenpolygon2
 	gdimageopenpolygon3
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagepolygon/CMakeLists.txt b/tests/gdimagepolygon/CMakeLists.txt
index 1b4ee83..647636a 100644
--- a/tests/gdimagepolygon/CMakeLists.txt
+++ b/tests/gdimagepolygon/CMakeLists.txt
@@ -1,8 +1,10 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	gdimagepolygon0
 	gdimagepolygon1
 	gdimagepolygon2
 	gdimagepolygon3
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagerectangle/CMakeLists.txt b/tests/gdimagerectangle/CMakeLists.txt
index 2567ae3..e2a2b81 100644
--- a/tests/gdimagerectangle/CMakeLists.txt
+++ b/tests/gdimagerectangle/CMakeLists.txt
@@ -1,9 +1,14 @@
 LIST(APPEND TESTS_FILES
 	bug00003
 	bug00106_gdimagerectangle
-	bug00299
 	github_bug_00172
 	point_ordering
 )
 
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	bug00299
+)
+ENDIF(PNG_FOUND)
+
 ADD_GD_TESTS()
diff --git a/tests/gdimagerectangle/Makemodule.am b/tests/gdimagerectangle/Makemodule.am
index ea9d52b..cd49b73 100644
--- a/tests/gdimagerectangle/Makemodule.am
+++ b/tests/gdimagerectangle/Makemodule.am
@@ -1,10 +1,14 @@
 libgd_test_programs += \
 	gdimagerectangle/bug00003 \
 	gdimagerectangle/bug00106_gdimagerectangle \
-	gdimagerectangle/bug00299 \
 	gdimagerectangle/github_bug_00172 \
 	gdimagerectangle/point_ordering
 
+if HAVE_LIBPNG
+libgd_test_programs += \
+	gdimagerectangle/bug00299
+endif
+
 EXTRA_DIST += \
 	gdimagerectangle/CMakeLists.txt \
 	gdimagerectangle/bug00299_exp.png
diff --git a/tests/gdimagerotate/CMakeLists.txt b/tests/gdimagerotate/CMakeLists.txt
index e5ea84a..7b8ab14 100644
--- a/tests/gdimagerotate/CMakeLists.txt
+++ b/tests/gdimagerotate/CMakeLists.txt
@@ -1,7 +1,9 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	bug00067
 	php_bug_64898
 	php_bug_65070
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagerotate/Makemodule.am b/tests/gdimagerotate/Makemodule.am
index 99b2398..116c851 100644
--- a/tests/gdimagerotate/Makemodule.am
+++ b/tests/gdimagerotate/Makemodule.am
@@ -1,10 +1,6 @@
-if HAVE_LIBJPEG
-libgd_test_programs += \
-	gdimagerotate/bug00067
-endif
-
 if HAVE_LIBPNG
 libgd_test_programs += \
+	gdimagerotate/bug00067 \
 	gdimagerotate/php_bug_64898 \
 	gdimagerotate/php_bug_65070
 endif
diff --git a/tests/gdimagerotate/php_bug_65070.c b/tests/gdimagerotate/php_bug_65070.c
index f1b5504..87a43ea 100644
--- a/tests/gdimagerotate/php_bug_65070.c
+++ b/tests/gdimagerotate/php_bug_65070.c
@@ -1,35 +1,33 @@
-/**

- * Regression test for <https://github.com/libgd/libgd/issues/319>

- *

- * We're testing that the rotated image actually has the requested background

- * color.

- */

-

-

-#include "gd.h"

-#include "gdtest.h"

-

-

-int main()

-{

-	gdImagePtr src, dst;

-	FILE *fp;

-	int black;

-	char *path;

-

-	fp = gdTestFileOpen2("gdimagerotate", "php_bug_65070.gif");

-	src = gdImageCreateFromGif(fp);

-	fclose(fp);

-

-	black = gdImageColorAllocateAlpha(src, 0, 0, 0, 0);

-	dst = gdImageRotateInterpolated(src, 30.0, black);

-

-	path = gdTestFilePath2("gdimagerotate", "php_bug_65070_exp.png");

-	gdAssertImageEqualsToFile(path, dst);

-	gdFree(path);

-

-	gdImageDestroy(src);

-	gdImageDestroy(dst);

-

-	return gdNumFailures();

-}

+/**
+ * Regression test for <https://github.com/libgd/libgd/issues/319>
+ *
+ * We're testing that the rotated image actually has the requested background
+ * color.
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr src, dst;
+	FILE *fp;
+	int black;
+	char *path;
+
+	fp = gdTestFileOpen2("gdimagerotate", "php_bug_65070.gif");
+	src = gdImageCreateFromGif(fp);
+	fclose(fp);
+
+	black = gdImageColorAllocateAlpha(src, 0, 0, 0, 0);
+	dst = gdImageRotateInterpolated(src, 30.0, black);
+
+	path = gdTestFilePath2("gdimagerotate", "php_bug_65070_exp.png");
+	gdAssertImageEqualsToFile(path, dst);
+	gdFree(path);
+
+	gdImageDestroy(src);
+	gdImageDestroy(dst);
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimagerotate/php_bug_65070_exp.png b/tests/gdimagerotate/php_bug_65070_exp.png
index fba85f6..64b8b10 100644
--- a/tests/gdimagerotate/php_bug_65070_exp.png
+++ b/tests/gdimagerotate/php_bug_65070_exp.png
diff --git a/tests/gdimagescale/.gitignore b/tests/gdimagescale/.gitignore
index cfa5549..e75e0bc 100644
--- a/tests/gdimagescale/.gitignore
+++ b/tests/gdimagescale/.gitignore
@@ -1,2 +1,4 @@
+/bug00329
+/bug00330
 /github_bug_00218
 /bug_overflow_large_new_size
diff --git a/tests/gdimagescale/CMakeLists.txt b/tests/gdimagescale/CMakeLists.txt
index f5ebf2e..1174e65 100644
--- a/tests/gdimagescale/CMakeLists.txt
+++ b/tests/gdimagescale/CMakeLists.txt
@@ -1,4 +1,6 @@
 LIST(APPEND TESTS_FILES
+	bug00329
+	bug00330
 	github_bug_00218
 	bug_overflow_large_new_size
 )
diff --git a/tests/gdimagescale/Makemodule.am b/tests/gdimagescale/Makemodule.am
index 23b8924..432ddbe 100644
--- a/tests/gdimagescale/Makemodule.am
+++ b/tests/gdimagescale/Makemodule.am
@@ -1,5 +1,6 @@
-
 libgd_test_programs += \
+	gdimagescale/bug00329 \
+	gdimagescale/bug00330 \
 	gdimagescale/github_bug_00218 \
 	gdimagescale/bug_overflow_large_new_size
 
diff --git a/tests/gdimagescale/bug00329.c b/tests/gdimagescale/bug00329.c
new file mode 100644
index 0000000..67a1561
--- /dev/null
+++ b/tests/gdimagescale/bug00329.c
@@ -0,0 +1,50 @@
+/**
+ * Regression test for <https://github.com/libgd/libgd/issues/329>
+ *
+ * We're testing that for truecolor as well as palette images after
+ * GD_BILINEAR_FIXED scaling the corner pixels of the scaled image have the
+ * expected color.
+ */
+
+#include <string.h>
+#include "gd.h"
+#include "gdtest.h"
+
+static void test(const char *mode)
+{
+	gdImagePtr src, dst;
+	int expected, actual;
+
+	if (strcmp(mode, "palette")) {
+		src = gdImageCreateTrueColor(100, 100);
+		expected = gdTrueColorAlpha(255, 255, 255, gdAlphaOpaque);
+		gdImageFilledRectangle(src, 0,0, 99,99, expected);
+	} else {
+		src = gdImageCreate(100, 100);
+		gdImageColorAllocate(src, 255, 255, 255);
+		expected = gdImageGetTrueColorPixel(src, 49, 49);
+	}
+
+	gdImageSetInterpolationMethod(src, GD_BILINEAR_FIXED);
+	dst = gdImageScale(src, 200, 200);
+
+	actual = gdImageGetPixel(dst, 0, 0);
+	gdTestAssertMsg(actual == expected, "%s: wrong color; expected %x, but got %x", mode, expected, actual);
+	actual = gdImageGetPixel(dst, 0, 199);
+	gdTestAssertMsg(actual == expected, "%s: wrong color; expected %x, but got %x", mode, expected, actual);
+	actual = gdImageGetPixel(dst, 199, 199);
+	gdTestAssertMsg(actual == expected, "%s: wrong color; expected %x, but got %x", mode, expected, actual);
+	actual = gdImageGetPixel(dst, 199, 0);
+	gdTestAssertMsg(actual == expected, "%s: wrong color; expected %x, but got %x", mode, expected, actual);
+
+	gdImageDestroy(src);
+	gdImageDestroy(dst);
+}
+
+int main()
+{
+	test("palette");
+	test("truecolor");
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimagescale/bug00330.c b/tests/gdimagescale/bug00330.c
new file mode 100644
index 0000000..44ba2f4
--- /dev/null
+++ b/tests/gdimagescale/bug00330.c
@@ -0,0 +1,30 @@
+/**
+ * Regression test for <https://github.com/libgd/libgd/issues/330>.
+ *
+ * We're testing that after scaling a palette image, the center pixel actually
+ * has the expected color value.
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr src, dst;
+	int color;
+
+	src = gdImageCreate(100, 100);
+	gdImageColorAllocate(src, 255, 255, 255);
+
+	gdImageSetInterpolationMethod(src, GD_BILINEAR_FIXED);
+	dst = gdImageScale(src, 200, 200);
+
+	color = gdImageGetPixel(dst, 99, 99);
+	gdTestAssertMsg(color == 0xffffff,
+	                "expected color ffffff, but got %x\n", color);
+
+	gdImageDestroy(src);
+	gdImageDestroy(dst);
+
+	return 0;
+}
diff --git a/tests/gdimagescale/bug_overflow_large_new_size.c b/tests/gdimagescale/bug_overflow_large_new_size.c
index 0a8503b..20cda1d 100644
--- a/tests/gdimagescale/bug_overflow_large_new_size.c
+++ b/tests/gdimagescale/bug_overflow_large_new_size.c
@@ -15,13 +15,14 @@ int main()
 		return 1;
 	}
 	gdImageSetInterpolationMethod(im, GD_BELL);
-	
+
 	/* here the call may pass if the system has enough memory (physical or swap)
 	   or fails (overflow check or alloc fails.
 	   in both cases the tests pass */
 	im2 = gdImageScale(im,0x15555556, 1);
 	if (im2 == NULL) {
 		printf("gdImageScale failed, expected (out of memory or overflow validation\n");
+		gdImageDestroy(im);
 		return 0;
 	}
 	gdImageDestroy(im);
diff --git a/tests/gdimagescatterex/CMakeLists.txt b/tests/gdimagescatterex/CMakeLists.txt
index 22c46a7..479afe5 100644
--- a/tests/gdimagescatterex/CMakeLists.txt
+++ b/tests/gdimagescatterex/CMakeLists.txt
@@ -1,6 +1,8 @@
+IF(PNG_FOUND)
 LIST(APPEND TESTS_FILES
 	bug00208_1
 	bug00208_2
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdimagesetinterpolationmethod/.gitignore b/tests/gdimagesetinterpolationmethod/.gitignore
new file mode 100644
index 0000000..db7b3af
--- /dev/null
+++ b/tests/gdimagesetinterpolationmethod/.gitignore
@@ -0,0 +1 @@
+/github_bug_00584
diff --git a/tests/gdimagesetinterpolationmethod/CMakeLists.txt b/tests/gdimagesetinterpolationmethod/CMakeLists.txt
new file mode 100644
index 0000000..6551062
--- /dev/null
+++ b/tests/gdimagesetinterpolationmethod/CMakeLists.txt
@@ -0,0 +1,5 @@
+LIST(APPEND TESTS_FILES
+	github_bug_00584
+)
+
+ADD_GD_TESTS()
diff --git a/tests/gdimagesetinterpolationmethod/Makemodule.am b/tests/gdimagesetinterpolationmethod/Makemodule.am
new file mode 100644
index 0000000..1b83336
--- /dev/null
+++ b/tests/gdimagesetinterpolationmethod/Makemodule.am
@@ -0,0 +1,5 @@
+libgd_test_programs += \
+	gdimagesetinterpolationmethod/github_bug_00584
+
+EXTRA_DIST += \
+	gdimagesetinterpolationmethod/CMakeLists.txt
diff --git a/tests/gdimagesetinterpolationmethod/github_bug_00584.c b/tests/gdimagesetinterpolationmethod/github_bug_00584.c
new file mode 100644
index 0000000..e11f9f0
--- /dev/null
+++ b/tests/gdimagesetinterpolationmethod/github_bug_00584.c
@@ -0,0 +1,31 @@
+/**
+ * Test that gdImageSetInterpolationMethod(im, GD_DEFAULT) is consistent
+ *
+ * See <https://github.com/libgd/libgd/issues/584>
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+    gdImagePtr im;
+    gdInterpolationMethod old_m, new_m;
+    interpolation_method old_f, new_f;
+
+    im = gdImageCreateTrueColor(8, 8);
+    gdTestAssert(im != NULL);
+    gdTestAssert(gdImageSetInterpolationMethod(im, GD_SINC));
+    old_m = gdImageGetInterpolationMethod(im);
+    gdTestAssert(old_m == GD_SINC);
+    old_f = im->interpolation;
+    gdTestAssert(gdImageSetInterpolationMethod(im, GD_DEFAULT));
+    new_m = gdImageGetInterpolationMethod(im);
+    gdTestAssert(new_m == GD_LINEAR);
+    new_f = im->interpolation;
+    gdTestAssert(new_m != old_m);
+    gdTestAssert(new_f != old_f);
+    gdImageDestroy(im);
+    return gdNumFailures();
+}
diff --git a/tests/gdimagesetpixel/CMakeLists.txt b/tests/gdimagesetpixel/CMakeLists.txt
index f363899..675bbfd 100644
--- a/tests/gdimagesetpixel/CMakeLists.txt
+++ b/tests/gdimagesetpixel/CMakeLists.txt
@@ -1,8 +1,13 @@
 LIST(APPEND TESTS_FILES
-	alpha_blending
 	bug00186
 	gdeffectoverlay
 	gdeffectmultiply
 )
 
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	alpha_blending
+)
+ENDIF(PNG_FOUND)
+
 ADD_GD_TESTS()
diff --git a/tests/gdimagesetpixel/Makemodule.am b/tests/gdimagesetpixel/Makemodule.am
index 0a574ad..1eb0224 100644
--- a/tests/gdimagesetpixel/Makemodule.am
+++ b/tests/gdimagesetpixel/Makemodule.am
@@ -1,9 +1,13 @@
 libgd_test_programs += \
-	gdimagesetpixel/alpha_blending \
 	gdimagesetpixel/bug00186 \
 	gdimagesetpixel/gdeffectmultiply \
 	gdimagesetpixel/gdeffectoverlay
 
+if HAVE_LIBPNG
+libgd_test_programs += \
+	gdimagesetpixel/alpha_blending
+endif
+
 EXTRA_DIST += \
 	gdimagesetpixel/CMakeLists.txt \
 	gdimagesetpixel/alphablending_exp.png
diff --git a/tests/gdimagesetpixel/alpha_blending.c b/tests/gdimagesetpixel/alpha_blending.c
index 394ced5..f182d59 100644
--- a/tests/gdimagesetpixel/alpha_blending.c
+++ b/tests/gdimagesetpixel/alpha_blending.c
@@ -1,54 +1,52 @@
-/**

- * Testing all effects

- */

-

-

-#include "gd.h"

-#include "gdtest.h"

-

-

-int main()

-{

-    gdImagePtr im;

-    int effects[] = {

-        gdEffectReplace, gdEffectAlphaBlend, gdEffectNormal,

-        gdEffectOverlay, gdEffectMultiply

-    };

-    int red[3], blue[3];

-    int x, y, i, j;

-    char *path;

-

-    red[0] = gdTrueColorAlpha(0, 0, 255, 127);

-    red[1] = gdTrueColorAlpha(0, 0, 255, 63);

-    red[2] = gdTrueColorAlpha(0, 0, 255, 0);

-    blue[0] = gdTrueColorAlpha(255, 0, 0, 127);

-    blue[1] = gdTrueColorAlpha(255, 0, 0, 63);

-    blue[2] = gdTrueColorAlpha(255, 0, 0, 0);

-

-    im = gdImageCreateTrueColor(120, 180);

-

-    gdImageAlphaBlending(im, gdEffectReplace);

-    for (j = 0; j < 3; j++) {

-        y = 60 * j;

-        gdImageFilledRectangle(im, 0,y, 119,y+59, red[j]);

-    }

-

-    for (i = 0; i < 5; i++) {

-        x = 20 * i;

-        gdImageAlphaBlending(im, effects[i]);

-        for (j = 0; j < 9; j++) {

-            y = 20 * j;

-            gdImageFilledRectangle(im, x+20,y, x+39,y+19, blue[j % 3]);

-        }

-    }

-

-    gdImageSaveAlpha(im, 1);

-

-    path = gdTestFilePath2("gdimagesetpixel", "alphablending_exp.png");

-    gdAssertImageEqualsToFile(path, im);

-    gdFree(path);

-

-    gdImageDestroy(im);

-

-    return gdNumFailures();

-}

+/**
+ * Testing all effects
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	int effects[] = {
+		gdEffectReplace, gdEffectAlphaBlend, gdEffectNormal,
+		gdEffectOverlay, gdEffectMultiply
+	};
+	int red[3], blue[3];
+	int x, y, i, j;
+	char *path;
+
+	red[0] = gdTrueColorAlpha(0, 0, 255, 127);
+	red[1] = gdTrueColorAlpha(0, 0, 255, 63);
+	red[2] = gdTrueColorAlpha(0, 0, 255, 0);
+	blue[0] = gdTrueColorAlpha(255, 0, 0, 127);
+	blue[1] = gdTrueColorAlpha(255, 0, 0, 63);
+	blue[2] = gdTrueColorAlpha(255, 0, 0, 0);
+
+	im = gdImageCreateTrueColor(120, 180);
+
+	gdImageAlphaBlending(im, gdEffectReplace);
+	for (j = 0; j < 3; j++) {
+		y = 60 * j;
+		gdImageFilledRectangle(im, 0,y, 119,y+59, red[j]);
+	}
+
+	for (i = 0; i < 5; i++) {
+		x = 20 * i;
+		gdImageAlphaBlending(im, effects[i]);
+		for (j = 0; j < 9; j++) {
+			y = 20 * j;
+			gdImageFilledRectangle(im, x+20,y, x+39,y+19, blue[j % 3]);
+		}
+	}
+
+	gdImageSaveAlpha(im, 1);
+
+	path = gdTestFilePath2("gdimagesetpixel", "alphablending_exp.png");
+	gdAssertImageEqualsToFile(path, im);
+	gdFree(path);
+
+	gdImageDestroy(im);
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimagesquaretocircle/.gitignore b/tests/gdimagesquaretocircle/.gitignore
new file mode 100644
index 0000000..bf6e191
--- /dev/null
+++ b/tests/gdimagesquaretocircle/.gitignore
@@ -0,0 +1 @@
+/gdimagesquaretocircle
diff --git a/tests/gdimagesquaretocircle/CMakeLists.txt b/tests/gdimagesquaretocircle/CMakeLists.txt
new file mode 100644
index 0000000..a8c9430
--- /dev/null
+++ b/tests/gdimagesquaretocircle/CMakeLists.txt
@@ -0,0 +1,7 @@
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	gdimagesquaretocircle
+)
+ENDIF(PNG_FOUND)
+
+ADD_GD_TESTS()
diff --git a/tests/gdimagesquaretocircle/Makemodule.am b/tests/gdimagesquaretocircle/Makemodule.am
new file mode 100644
index 0000000..77b7a30
--- /dev/null
+++ b/tests/gdimagesquaretocircle/Makemodule.am
@@ -0,0 +1,8 @@
+if HAVE_LIBPNG
+libgd_test_programs += \
+	gdimagesquaretocircle/gdimagesquaretocircle
+endif
+
+EXTRA_DIST += \
+	gdimagesquaretocircle/CMakeLists.txt \
+	gdimagesquaretocircle/gdimagesquaretocircle_exp.png
diff --git a/tests/gdimagesquaretocircle/gdimagesquaretocircle.c b/tests/gdimagesquaretocircle/gdimagesquaretocircle.c
new file mode 100644
index 0000000..f8fba91
--- /dev/null
+++ b/tests/gdimagesquaretocircle/gdimagesquaretocircle.c
@@ -0,0 +1,32 @@
+/**
+ * Basic test for gdImageSquareToCircle()
+ */
+#include "gd.h"
+#include "gdfx.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im1, im2;
+	int white;
+	int black;
+
+	im1 = gdImageCreateTrueColor(128, 128);
+	white = gdImageColorAllocate(im1, 255, 255, 255);
+	black = gdImageColorAllocate(im1, 0, 0, 0);
+	gdImageFilledRectangle(im1, 0, 0, 127, 127, white);
+
+	/* Draw a cross line in the middle of im1 */
+	/* The horizonal line will become a circle in im2 */
+	/* The vertical line will become a horizonal with half len in im2 */
+	gdImageLine(im1, 0, 63, 127, 63, black);
+	gdImageLine(im1, 63, 0, 63, 127, black);
+	im2 = gdImageSquareToCircle(im1, 64);
+
+	gdAssertImageEqualsToFile("gdimagesquaretocircle/gdimagesquaretocircle_exp.png", im2);
+
+	gdImageDestroy(im1);
+	gdImageDestroy(im2);
+
+	return gdNumFailures();
+}
diff --git a/tests/gdimagesquaretocircle/gdimagesquaretocircle_exp.png b/tests/gdimagesquaretocircle/gdimagesquaretocircle_exp.png
new file mode 100644
index 0000000..222bb13
--- /dev/null
+++ b/tests/gdimagesquaretocircle/gdimagesquaretocircle_exp.png
diff --git a/tests/gdimagestring/.gitignore b/tests/gdimagestring/.gitignore
new file mode 100644
index 0000000..ecd076c
--- /dev/null
+++ b/tests/gdimagestring/.gitignore
@@ -0,0 +1 @@
+/gdimagestring
diff --git a/tests/gdimagestring/CMakeLists.txt b/tests/gdimagestring/CMakeLists.txt
new file mode 100644
index 0000000..3cabaec
--- /dev/null
+++ b/tests/gdimagestring/CMakeLists.txt
@@ -0,0 +1,7 @@
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	gdimagestring
+)
+ENDIF(PNG_FOUND)
+
+ADD_GD_TESTS()
diff --git a/tests/gdimagestring/Makemodule.am b/tests/gdimagestring/Makemodule.am
new file mode 100644
index 0000000..84ca656
--- /dev/null
+++ b/tests/gdimagestring/Makemodule.am
@@ -0,0 +1,8 @@
+if HAVE_LIBPNG
+libgd_test_programs += \
+	gdimagestring/gdimagestring
+endif
+
+EXTRA_DIST += \
+	gdimagestring/CMakeLists.txt \
+	gdimagestring/gdimagestring_exp.png
diff --git a/tests/gdimagestring/gdimagestring.c b/tests/gdimagestring/gdimagestring.c
new file mode 100644
index 0000000..c4b4aa1
--- /dev/null
+++ b/tests/gdimagestring/gdimagestring.c
@@ -0,0 +1,34 @@
+/**
+ * Base test for gdImageString()
+ */
+#include <gd.h>
+#include <gdfontl.h>
+#include "gdtest.h"
+#include <string.h>
+
+int main()
+{
+	/* Declare the image */
+	gdImagePtr im = NULL;
+	char *s = "Hello gd";
+	int foreground = 0;
+	int error = 0;
+	gdFontPtr fontptr = gdFontGetLarge();
+
+	im = gdImageCreate(100, 50);
+	gdImageColorAllocate(im, 202, 202, 0);
+	foreground = gdImageColorAllocate(im, 22, 4, 238);
+
+	gdImageString(im, fontptr,
+			im->sx / 2 - (strlen(s) * fontptr->w / 2),
+			im->sy / 2 - fontptr->h / 2,
+			(unsigned char*)s, foreground);
+
+	if (!gdAssertImageEqualsToFile("gdimagestring/gdimagestring_exp.png", im))
+		error= 1;
+
+	/* Destroy the image in memory. */
+	gdImageDestroy(im);
+
+	return error;
+}
diff --git a/tests/gdimagestring/gdimagestring_exp.png b/tests/gdimagestring/gdimagestring_exp.png
new file mode 100644
index 0000000..2435626
--- /dev/null
+++ b/tests/gdimagestring/gdimagestring_exp.png
diff --git a/tests/gdimagestring16/.gitignore b/tests/gdimagestring16/.gitignore
new file mode 100644
index 0000000..5ebaa0b
--- /dev/null
+++ b/tests/gdimagestring16/.gitignore
@@ -0,0 +1 @@
+/gdimagestring16
diff --git a/tests/gdimagestring16/CMakeLists.txt b/tests/gdimagestring16/CMakeLists.txt
new file mode 100644
index 0000000..e85db9b
--- /dev/null
+++ b/tests/gdimagestring16/CMakeLists.txt
@@ -0,0 +1,7 @@
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	gdimagestring16
+)
+ENDIF(PNG_FOUND)
+
+ADD_GD_TESTS()
diff --git a/tests/gdimagestring16/Makemodule.am b/tests/gdimagestring16/Makemodule.am
new file mode 100644
index 0000000..84b6b5f
--- /dev/null
+++ b/tests/gdimagestring16/Makemodule.am
@@ -0,0 +1,8 @@
+if HAVE_LIBPNG
+libgd_test_programs += \
+	gdimagestring16/gdimagestring16
+endif
+
+EXTRA_DIST += \
+	gdimagestring16/CMakeLists.txt \
+	gdimagestring16/gdimagestring16_exp.png
diff --git a/tests/gdimagestring16/gdimagestring16.c b/tests/gdimagestring16/gdimagestring16.c
new file mode 100644
index 0000000..0ca0668
--- /dev/null
+++ b/tests/gdimagestring16/gdimagestring16.c
@@ -0,0 +1,30 @@
+/**
+ * Base test for gdImageString16()
+ */
+#include <gd.h>
+#include <gdfontl.h>
+#include "gdtest.h"
+
+int main()
+{
+	/* Declare the image */
+	gdImagePtr im = NULL;
+	unsigned short s[2] = {'H', 0};
+	int foreground;
+	int errorcode = 0;
+	gdFontPtr fontptr = gdFontGetLarge();
+
+	im = gdImageCreate(20, 20);
+	gdImageColorAllocate(im, 255, 255, 255);
+	foreground = gdImageColorAllocate(im, 22, 4, 238);
+
+	gdImageString16(im, fontptr, 2, 2, s, foreground);
+
+	if (!gdAssertImageEqualsToFile("gdimagestring16/gdimagestring16_exp.png", im))
+		errorcode = 1;
+
+	/* Destroy the image in memory */
+	gdImageDestroy(im);
+
+	return errorcode;
+}
diff --git a/tests/gdimagestring16/gdimagestring16_exp.png b/tests/gdimagestring16/gdimagestring16_exp.png
new file mode 100644
index 0000000..5700578
--- /dev/null
+++ b/tests/gdimagestring16/gdimagestring16_exp.png
diff --git a/tests/gdimagestringft/.gitignore b/tests/gdimagestringft/.gitignore
index f9f01f0..efe5e61 100644
--- a/tests/gdimagestringft/.gitignore
+++ b/tests/gdimagestringft/.gitignore
@@ -1 +1,2 @@
+/bug00615
 /gdimagestringft_bbox
diff --git a/tests/gdimagestringft/CMakeLists.txt b/tests/gdimagestringft/CMakeLists.txt
index f46b900..42868a2 100644
--- a/tests/gdimagestringft/CMakeLists.txt
+++ b/tests/gdimagestringft/CMakeLists.txt
@@ -1,5 +1,6 @@
 IF(FREETYPE_FOUND)
 LIST(APPEND TESTS_FILES
+	bug00615
 	gdimagestringft_bbox
 )
 ENDIF(FREETYPE_FOUND)
diff --git a/tests/gdimagestringft/Makemodule.am b/tests/gdimagestringft/Makemodule.am
index 0dfe26f..a62081f 100644
--- a/tests/gdimagestringft/Makemodule.am
+++ b/tests/gdimagestringft/Makemodule.am
@@ -1,5 +1,6 @@
 if HAVE_LIBFREETYPE
 libgd_test_programs += \
+	gdimagestringft/bug00615 \
 	gdimagestringft/gdimagestringft_bbox
 endif
 
diff --git a/tests/gdimagestringft/bug00615.c b/tests/gdimagestringft/bug00615.c
new file mode 100644
index 0000000..0da51da
--- /dev/null
+++ b/tests/gdimagestringft/bug00615.c
@@ -0,0 +1,25 @@
+/**
+ * Test that rendering an empty string does not fail
+ *
+ * Rendering an empty string with gdImageStringFT() is not supposed to fail;
+ * it is just a no-op.
+ *
+ * See <https://github.com/libgd/libgd/issues/615>
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+    gdImagePtr im = gdImageCreate(100, 100);
+
+    int rect[8];
+    int fg = gdImageColorAllocate(im, 255, 255, 255);
+    char *path = gdTestFilePath("freetype/DejaVuSans.ttf");
+    char *res = gdImageStringFT(im, rect, fg, path, 12, 0, 10, 10, "");
+
+    gdTestAssert(res == NULL);
+
+    return gdNumFailures();
+}
diff --git a/tests/gdimagestringft/gdimagestringft_bbox.c b/tests/gdimagestringft/gdimagestringft_bbox.c
index 0161ec8..e75248a 100644
--- a/tests/gdimagestringft/gdimagestringft_bbox.c
+++ b/tests/gdimagestringft/gdimagestringft_bbox.c
@@ -8,22 +8,22 @@
 #define DELTA (PI/8)
 
 static int EXPECT[16][8] = {
-	{498, 401, 630, 401, 630, 374, 498, 374},
-	{491, 364, 613, 313, 602, 288, 481, 338},
-	{470, 332, 563, 239, 544, 219, 451, 312},
-	{438, 310, 488, 189, 463, 178, 412, 300},
-	{401, 303, 401, 171, 374, 171, 374, 303},
-	{365, 310, 314, 188, 289, 199, 339, 320},
-	{334, 331, 241, 238, 221, 257, 314, 350},
-	{313, 362, 192, 312, 181, 337, 303, 388},
-	{306, 398, 174, 398, 174, 425, 306, 425},
-	{313, 433, 191, 484, 202, 509, 323, 459},
-	{333, 463, 240, 556, 259, 576, 352, 483},
-	{363, 484, 313, 605, 338, 616, 389, 494},
-	{398, 490, 398, 622, 425, 622, 425, 490},
-	{432, 483, 483, 605, 508, 594, 458, 473},
-	{461, 464, 554, 557, 574, 538, 481, 445},
-	{481, 435, 602, 485, 613, 460, 491, 409},
+	{500, 400, 628, 400, 628, 376, 500, 376},
+	{492, 362, 611, 312, 601, 290, 483, 339},
+	{470, 330, 561, 239, 544, 221, 453, 312},
+	{437, 308, 486, 189, 464, 180, 414, 299},
+	{400, 301, 400, 173, 376, 173, 376, 301},
+	{363, 309, 313, 190, 291, 200, 340, 318},
+	{332, 331, 241, 240, 223, 257, 314, 348},
+	{311, 363, 192, 314, 183, 336, 302, 386},
+	{304, 399, 176, 399, 176, 423, 304, 423},
+	{312, 435, 193, 485, 203, 507, 321, 458},
+	{333, 465, 242, 556, 259, 574, 350, 483},
+	{364, 486, 315, 605, 337, 614, 387, 495},
+	{399, 492, 399, 620, 423, 620, 423, 492},
+	{434, 484, 484, 603, 506, 593, 457, 475},
+	{463, 464, 554, 555, 572, 538, 481, 447},
+	{483, 434, 602, 483, 611, 461, 492, 411},
 };
 
 int main()
@@ -38,6 +38,9 @@ int main()
 	int error = 0;
 	FILE *fp;
 
+	/* disable subpixel hinting */
+	putenv("FREETYPE_PROPERTIES=truetype:interpreter-version=35");
+
 	path = gdTestFilePath("freetype/DejaVuSans.ttf");
 	im = gdImageCreate(800, 800);
 	gdImageColorAllocate(im, 0xFF, 0xFF, 0xFF); /* allocate white for background color */
@@ -52,7 +55,7 @@ int main()
 			goto done;
 		}
 		for (j = 0; j < 8; j++) {
-			if (brect[j] != EXPECT[i][j]) {
+			if (brect[j] < EXPECT[i][j] - 1 || brect[j] > EXPECT[i][j] + 1) {
 				gdTestErrorMsg("(%d, %d) (%d, %d) (%d, %d) (%d, %d) expected, but (%d, %d) (%d, %d) (%d, %d) (%d, %d)\n",
 				       EXPECT[i][0], EXPECT[i][1], EXPECT[i][2], EXPECT[i][3],
 				       EXPECT[i][4], EXPECT[i][5], EXPECT[i][6], EXPECT[i][7],
diff --git a/tests/gdimagestringup/.gitignore b/tests/gdimagestringup/.gitignore
new file mode 100644
index 0000000..4b4bb43
--- /dev/null
+++ b/tests/gdimagestringup/.gitignore
@@ -0,0 +1 @@
+/gdimagestringup
diff --git a/tests/gdimagestringup/CMakeLists.txt b/tests/gdimagestringup/CMakeLists.txt
new file mode 100644
index 0000000..424cb83
--- /dev/null
+++ b/tests/gdimagestringup/CMakeLists.txt
@@ -0,0 +1,7 @@
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	gdimagestringup
+)
+ENDIF(PNG_FOUND)
+
+ADD_GD_TESTS()
diff --git a/tests/gdimagestringup/Makemodule.am b/tests/gdimagestringup/Makemodule.am
new file mode 100644
index 0000000..b136c80
--- /dev/null
+++ b/tests/gdimagestringup/Makemodule.am
@@ -0,0 +1,8 @@
+if HAVE_LIBPNG
+libgd_test_programs += \
+	gdimagestringup/gdimagestringup
+endif
+
+EXTRA_DIST += \
+	gdimagestringup/CMakeLists.txt \
+	gdimagestringup/gdimagestringup_exp.png
diff --git a/tests/gdimagestringup/gdimagestringup.c b/tests/gdimagestringup/gdimagestringup.c
new file mode 100644
index 0000000..0832bd7
--- /dev/null
+++ b/tests/gdimagestringup/gdimagestringup.c
@@ -0,0 +1,34 @@
+/**
+ * Base test for gdImageStringUp()
+ */
+#include <gd.h>
+#include <gdfontl.h>
+#include "gdtest.h"
+#include <string.h>
+
+int main()
+{
+	/* Declare the image */
+	gdImagePtr im = NULL;
+	char *s = "Hello gd";
+	int errorcode = 0;
+	int foreground;
+	gdFontPtr fontptr = gdFontGetLarge();
+
+	im = gdImageCreate(50, 100);
+	gdImageColorAllocate(im, 202, 202, 0);
+	foreground = gdImageColorAllocate(im, 22, 4, 238);
+
+	gdImageStringUp(im, fontptr,
+			im->sx / 2 - fontptr->h / 2,
+			im->sy / 2 + (strlen(s) * fontptr->w / 2),
+			(unsigned char*)s, foreground);
+
+	if (!gdAssertImageEqualsToFile("gdimagestringup/gdimagestringup_exp.png", im))
+		errorcode = 1;
+
+	/* Destroy the image im memory */
+	gdImageDestroy(im);
+
+	return errorcode;
+}
diff --git a/tests/gdimagestringup/gdimagestringup_exp.png b/tests/gdimagestringup/gdimagestringup_exp.png
new file mode 100644
index 0000000..d1f6d66
--- /dev/null
+++ b/tests/gdimagestringup/gdimagestringup_exp.png
diff --git a/tests/gdimagestringup16/.gitignore b/tests/gdimagestringup16/.gitignore
new file mode 100644
index 0000000..1c009a5
--- /dev/null
+++ b/tests/gdimagestringup16/.gitignore
@@ -0,0 +1 @@
+/gdimagestringup16
diff --git a/tests/gdimagestringup16/CMakeLists.txt b/tests/gdimagestringup16/CMakeLists.txt
new file mode 100644
index 0000000..08f4ff8
--- /dev/null
+++ b/tests/gdimagestringup16/CMakeLists.txt
@@ -0,0 +1,7 @@
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	gdimagestringup16
+)
+ENDIF(PNG_FOUND)
+
+ADD_GD_TESTS()
diff --git a/tests/gdimagestringup16/Makemodule.am b/tests/gdimagestringup16/Makemodule.am
new file mode 100644
index 0000000..7735432
--- /dev/null
+++ b/tests/gdimagestringup16/Makemodule.am
@@ -0,0 +1,8 @@
+if HAVE_LIBPNG
+libgd_test_programs += \
+	gdimagestringup16/gdimagestringup16
+endif
+
+EXTRA_DIST += \
+	gdimagestringup16/CMakeLists.txt \
+	gdimagestringup16/gdimagestringup16_exp.png
diff --git a/tests/gdimagestringup16/gdimagestringup16.c b/tests/gdimagestringup16/gdimagestringup16.c
new file mode 100644
index 0000000..c24639f
--- /dev/null
+++ b/tests/gdimagestringup16/gdimagestringup16.c
@@ -0,0 +1,29 @@
+/**
+ * Base test for gdImageStringUp16()
+ */
+#include <gd.h>
+#include <gdfontl.h>
+#include "gdtest.h"
+
+int main()
+{
+	/* Declare the image */
+	gdImagePtr im = NULL;
+	unsigned short s[2] = {'H', 0};
+	int foreground;
+	int errorcode = 0;
+	gdFontPtr fontptr = gdFontGetLarge();
+
+	im = gdImageCreate(20, 20);
+	gdImageColorAllocate(im, 255, 255, 255);
+	foreground = gdImageColorAllocate(im, 22, 4, 238);
+
+	gdImageStringUp16(im, fontptr, 2, 18, s, foreground);
+
+	if (!gdAssertImageEqualsToFile("gdimagestringup16/gdimagestringup16_exp.png", im))
+		errorcode = 1;
+
+	gdImageDestroy(im);
+
+	return errorcode;
+}
diff --git a/tests/gdimagestringup16/gdimagestringup16_exp.png b/tests/gdimagestringup16/gdimagestringup16_exp.png
new file mode 100644
index 0000000..a1a4570
--- /dev/null
+++ b/tests/gdimagestringup16/gdimagestringup16_exp.png
diff --git a/tests/gdimagetruecolortopalette/CMakeLists.txt b/tests/gdimagetruecolortopalette/CMakeLists.txt
index b23d2a1..fc7f6f7 100644
--- a/tests/gdimagetruecolortopalette/CMakeLists.txt
+++ b/tests/gdimagetruecolortopalette/CMakeLists.txt
@@ -1,4 +1,4 @@
-SET(TESTS_FILES
+LIST(APPEND TESTS_FILES
 	bug00307
 	php_bug_72512
 )
diff --git a/tests/gdimagetruecolortopalette/Makemodule.am b/tests/gdimagetruecolortopalette/Makemodule.am
index 31f0362..ac9eedc 100644
--- a/tests/gdimagetruecolortopalette/Makemodule.am
+++ b/tests/gdimagetruecolortopalette/Makemodule.am
@@ -1,4 +1,3 @@
-
 libgd_test_programs += \
 	gdimagetruecolortopalette/bug00307 \
 	gdimagetruecolortopalette/php_bug_72512
diff --git a/tests/gdimagetruecolortopalette/bug00307.c b/tests/gdimagetruecolortopalette/bug00307.c
index a5c6a04..a01eb5a 100644
--- a/tests/gdimagetruecolortopalette/bug00307.c
+++ b/tests/gdimagetruecolortopalette/bug00307.c
@@ -5,7 +5,7 @@
  * GD_QUANT_NEUQUANT has its trueColor flag unset.
  */
 
- 
+
 #include "gd.h"
 #include "gdtest.h"
 
diff --git a/tests/gdtest/CMakeLists.txt b/tests/gdtest/CMakeLists.txt
index 4b05262..ff9fd7d 100644
--- a/tests/gdtest/CMakeLists.txt
+++ b/tests/gdtest/CMakeLists.txt
@@ -1,3 +1,7 @@
 add_definitions(-DGDTEST_TOP_DIR="${CMAKE_CURRENT_SOURCE_DIR}/..")
-add_library (gdTest STATIC gdtest.c)
+SET(GDTEST_FILES gdtest.c)
+if(WIN32)
+	LIST(APPEND GDTEST_FILES readdir.c)
+endif()
+add_library(gdTest STATIC ${GDTEST_FILES})
 target_link_libraries(gdTest ${GD_LIB})
diff --git a/tests/gdtest/gdtest.c b/tests/gdtest/gdtest.c
index d173975..832f27a 100644
--- a/tests/gdtest/gdtest.c
+++ b/tests/gdtest/gdtest.c
@@ -1,4 +1,6 @@
+#ifdef HAVE_CONFIG_H
 #include <config.h>
+#endif
 #include <assert.h>
 #include <setjmp.h>
 #include <stdlib.h>
@@ -21,7 +23,14 @@
 #endif
 
 #ifdef _WIN32
-# include "readdir.h"
+#include "readdir.h"
+#include <errno.h>
+#endif
+
+/* GDTEST_TOP_DIR is defined in other compile ways except msys
+ * test_config.h is created by windows/msys/run_test.sh*/
+#ifndef GDTEST_TOP_DIR
+#include <test_config.h>
 #endif
 
 #include "gd.h"
@@ -59,7 +68,7 @@ gdImagePtr gdTestImageFromPng(const char *filename)
 	if (fp == NULL) {
 		return NULL;
 	}
-	
+
 	image = gdImageCreateFromPng(fp);
 	fclose(fp);
 	return image;
@@ -186,11 +195,11 @@ static int getfilesystemtime(struct timeval *tv)
 	fft.LowPart = ft.dwLowDateTime;
 	ff = fft.QuadPart;
 
-	ff /= 10Ui64; /* convert to microseconds */
-	ff -= 11644473600000000Ui64; /* convert to unix epoch */
+	ff /= 10ULL; /* convert to microseconds */
+	ff -= 11644473600000000ULL; /* convert to unix epoch */
 
-	tv->tv_sec = (long)(ff / 1000000Ui64);
-	tv->tv_usec = (long)(ff % 1000000Ui64);
+	tv->tv_sec = (long)(ff / 1000000ULL);
+	tv->tv_usec = (long)(ff % 1000000ULL);
 
 	return 0;
 }
@@ -203,7 +212,7 @@ mkdtemp (char *tmpl)
 	static int counter = 0;
 	char *XXXXXX;
 	struct timeval tv;
-	_int64 value;
+	__int64 value;
 	int count;
 
 	/* find the last occurrence of "XXXXXX" */
@@ -219,7 +228,7 @@ mkdtemp (char *tmpl)
 	value = (tv.tv_usec ^ tv.tv_sec) + counter++;
 
 	for (count = 0; count < 100; value += 7777, ++count) {
-		_int64 v = value;
+		__int64 v = value;
 
 		/* Fill in the random bits.  */
 		XXXXXX[0] = letters[v % NLETTERS];
@@ -304,7 +313,7 @@ char *gdTestTempFile(const char *template)
 										  ret);
 				gdTestAssert(error != 0);
 		} else {
-			sprintf(ret, "%s\\%s", tempdir, template);		
+			sprintf(ret, "%s\\%s", tempdir, template);
 		}
 	}
 #else
@@ -501,7 +510,6 @@ unsigned int gdMaxPixelDiff(gdImagePtr a, gdImagePtr b)
     return diff;
 }
 
-
 int gdTestImageCompareToImage(const char* file, unsigned int line, const char* message,
                               gdImagePtr expected, gdImagePtr actual)
 {
@@ -561,6 +569,7 @@ int gdTestImageCompareToImage(const char* file, unsigned int line, const char* m
 		if (!fp) goto fail;
 		gdImagePng(surface_diff,fp);
 		fclose(fp);
+		gdImageDestroy(surface_diff);
 
 		fp = fopen(file_out, "wb");
 		if (!fp) goto fail;
@@ -578,13 +587,13 @@ fail:
 	if (surface_diff) {
 		gdImageDestroy(surface_diff);
 	}
-	return 0;
+	return 1;
 }
 
 int gdTestImageCompareToFile(const char* file, unsigned int line, const char* message,
                              const char *expected_file, gdImagePtr actual)
 {
-	gdImagePtr expected;
+	gdImagePtr expected = 0;
 	int res = 1;
 
 	expected = gdTestImageFromPng(expected_file);
@@ -599,7 +608,6 @@ int gdTestImageCompareToFile(const char* file, unsigned int line, const char* me
 	return res;
 }
 
-
 static int failureCount = 0;
 
 int gdNumFailures() {
diff --git a/tests/gdtest/gdtest.h b/tests/gdtest/gdtest.h
index eecf5f6..16d89aa 100644
--- a/tests/gdtest/gdtest.h
+++ b/tests/gdtest/gdtest.h
@@ -63,10 +63,8 @@ int _gdTestErrorMsg(const char* file, unsigned int line, const char* string, ...
 
 /* public assert functions */
 #define gdAssertImageEqualsToFile(ex,ac) gdTestImageCompareToFile(__FILE__,__LINE__,NULL,(ex),(ac))
-#define gdAssertImageFileEqualsMsg(ex,ac,ms) gdTestImageCompareFiles(__FILE__,__LINE__,(ms),(ex),(ac))
 
 #define gdAssertImageEquals(ex,ac) gdTestImageCompareToImage(__FILE__,__LINE__,NULL,(ex),(ac))
-#define gdAssertImageEqualsMsg(ex,ac,ms) gdTestImageCompareToImage(__FILE__,__LINE__,(ms),(ex),(ac))
 
 #define gdTestAssert(cond) _gdTestAssert(__FILE__, __LINE__, (cond))
 
diff --git a/tests/gdtiled/CMakeLists.txt b/tests/gdtiled/CMakeLists.txt
index 921d00e..25f6045 100644
--- a/tests/gdtiled/CMakeLists.txt
+++ b/tests/gdtiled/CMakeLists.txt
@@ -1,5 +1,9 @@
+IF(PNG_FOUND)
+IF(ZLIB_FOUND)
 LIST(APPEND TESTS_FILES
 	bug00032
 )
+ENDIF(ZLIB_FOUND)
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gdtiled/bug00032.c b/tests/gdtiled/bug00032.c
index 4c788e2..7a2b5cc 100644
--- a/tests/gdtiled/bug00032.c
+++ b/tests/gdtiled/bug00032.c
@@ -29,4 +29,3 @@ int main()
 	gdImageDestroy(tile);
 	return 0;
 }
-
diff --git a/tests/gdtransformaffineboundingbox/Makemodule.am b/tests/gdtransformaffineboundingbox/Makemodule.am
index e70b073..2566ed5 100644
--- a/tests/gdtransformaffineboundingbox/Makemodule.am
+++ b/tests/gdtransformaffineboundingbox/Makemodule.am
@@ -1,4 +1,3 @@
-
 libgd_test_programs += \
 	gdtransformaffineboundingbox/github_bug_00221
 
diff --git a/tests/gdtransformaffineboundingbox/github_bug_00221.c b/tests/gdtransformaffineboundingbox/github_bug_00221.c
index c327789..9e75d0e 100644
--- a/tests/gdtransformaffineboundingbox/github_bug_00221.c
+++ b/tests/gdtransformaffineboundingbox/github_bug_00221.c
@@ -10,7 +10,7 @@ int main()
 		gdRect bbox;
 		gdRect area;
 		double affine[6];
-		
+
 		affine[0] = -0.965926;
 		affine[1] = -0.258819;
 		affine[2] =  0.258819;
@@ -24,7 +24,7 @@ int main()
 		if (gdTransformAffineBoundingBox(&area, affine, &bbox) != GD_TRUE) {
 			return 1;
 		}
-		if (!(bbox.x ==-253 &&  bbox.y ==-228 && bbox.width == 298 && bbox.height == 230)) {
+		if (!(bbox.x ==-253 &&  bbox.y ==-228 && bbox.width == 297 && bbox.height == 229)) {
 			return 1;
 		}
 
diff --git a/tests/gdtransformaffinecopy/.gitignore b/tests/gdtransformaffinecopy/.gitignore
new file mode 100644
index 0000000..2af21d5
--- /dev/null
+++ b/tests/gdtransformaffinecopy/.gitignore
@@ -0,0 +1,4 @@
+/github_bug_00583
+/github_bug_00585
+/github_bug_00586
+/github_bug_00596
diff --git a/tests/gdtransformaffinecopy/CMakeLists.txt b/tests/gdtransformaffinecopy/CMakeLists.txt
new file mode 100644
index 0000000..4af9fcc
--- /dev/null
+++ b/tests/gdtransformaffinecopy/CMakeLists.txt
@@ -0,0 +1,8 @@
+LIST(APPEND TESTS_FILES
+	github_bug_00583
+	github_bug_00585
+	github_bug_00586
+	github_bug_00596
+)
+
+ADD_GD_TESTS()
diff --git a/tests/gdtransformaffinecopy/Makemodule.am b/tests/gdtransformaffinecopy/Makemodule.am
new file mode 100644
index 0000000..494ec80
--- /dev/null
+++ b/tests/gdtransformaffinecopy/Makemodule.am
@@ -0,0 +1,8 @@
+libgd_test_programs += \
+	gdtransformaffinecopy/github_bug_00583 \
+	gdtransformaffinecopy/github_bug_00585 \
+	gdtransformaffinecopy/github_bug_00586 \
+	gdtransformaffinecopy/github_bug_00596
+
+EXTRA_DIST += \
+	gdtransformaffinecopy/CMakeLists.txt
diff --git a/tests/gdtransformaffinecopy/github_bug_00583.c b/tests/gdtransformaffinecopy/github_bug_00583.c
new file mode 100644
index 0000000..6b0fd53
--- /dev/null
+++ b/tests/gdtransformaffinecopy/github_bug_00583.c
@@ -0,0 +1,30 @@
+/**
+ * Test that a zero determinant matrix causes gdTransformAffineCopy() to fail
+ *
+ * See <https://github.com/libgd/libgd/issues/583>
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+    gdImagePtr src, dst;
+    gdRect rect = {0, 0, 8, 8};
+    double matrix[] = {1, 1, 1, 1, 1, 1};
+    int white;
+    int res;
+
+    src = gdImageCreateTrueColor(8, 8);
+    gdTestAssert(src != NULL);
+    dst = gdImageCreateTrueColor(8, 8);
+    gdTestAssert(dst != NULL);
+    white = gdImageColorAllocate(src, 255, 255, 255);
+    gdImageFilledRectangle(src, 0, 0, 7, 7, white);
+    res = gdTransformAffineCopy(dst, 0, 0, src, &rect, matrix);
+    gdTestAssert(res == GD_FALSE);
+    gdImageDestroy(dst);
+    gdImageDestroy(src);
+    return gdNumFailures();
+}
diff --git a/tests/gdtransformaffinecopy/github_bug_00585.c b/tests/gdtransformaffinecopy/github_bug_00585.c
new file mode 100644
index 0000000..e83910c
--- /dev/null
+++ b/tests/gdtransformaffinecopy/github_bug_00585.c
@@ -0,0 +1,33 @@
+/*
+ * Test that gdTransformAffineCopy() does not change the interpolation method
+ *
+ * See <https://github.com/libgd/libgd/issues/585>
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr src, dst;
+	gdRect rect = {0, 0, 8, 8};
+	double matrix[] = {1, 1, 1, 1, 1, 1};
+	int res;
+	gdInterpolationMethod old_m, new_m;
+
+	src = gdImageCreateTrueColor(8, 8);
+	gdTestAssert(src != NULL);
+	dst = gdImageCreateTrueColor(8, 8);
+	gdTestAssert(dst != NULL);
+
+	res = gdImageSetInterpolationMethod(src, GD_CATMULLROM);
+	gdTestAssert(res == GD_TRUE);
+	old_m = gdImageGetInterpolationMethod(src);
+	gdTransformAffineCopy(dst, 0, 0, src, &rect, matrix);
+	new_m = gdImageGetInterpolationMethod(src);
+	gdTestAssert(new_m == old_m);
+
+	gdImageDestroy(src);
+	gdImageDestroy(dst);
+	return gdNumFailures();
+}
diff --git a/tests/gdtransformaffinecopy/github_bug_00586.c b/tests/gdtransformaffinecopy/github_bug_00586.c
new file mode 100644
index 0000000..4cf2f2e
--- /dev/null
+++ b/tests/gdtransformaffinecopy/github_bug_00586.c
@@ -0,0 +1,26 @@
+/*
+ * Test that gdTransformAffineCopy() does not segfault for palette images
+ *
+ * See <>
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr src, dst;
+	gdRect rect = {0, 0, 8, 8};
+	double matrix[] = {1, 0, 0, 1, 0, 0};
+
+	src = gdImageCreate(8, 8);
+	gdTestAssert(src != NULL);
+	dst = gdImageCreate(8, 8);
+	gdTestAssert(dst != NULL);
+
+	gdTransformAffineCopy(dst, 0, 0, src, &rect, matrix);
+
+	gdImageDestroy(dst);
+	gdImageDestroy(src);
+	return gdNumFailures();
+}
diff --git a/tests/gdtransformaffinecopy/github_bug_00596.c b/tests/gdtransformaffinecopy/github_bug_00596.c
new file mode 100644
index 0000000..51912e1
--- /dev/null
+++ b/tests/gdtransformaffinecopy/github_bug_00596.c
@@ -0,0 +1,42 @@
+/**
+ * Test gdTransformAffineCopy() run error
+ *
+ * See <https://github.com/libgd/libgd/issues/596>
+ *
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	double matrix[] = {1, 0, 0, 1, 0, 0};
+	gdImagePtr src, dst;
+	gdRect rect = {0, 0, 16, 16};
+	int white, green;
+	int status = 0;
+	int res;
+	int actual_color = 0;
+	int expected_color = 0x00ff00;
+
+	src = gdImageCreateTrueColor(16, 16);
+	gdTestAssert(src != NULL);
+	white = gdImageColorAllocate(src, 255, 255, 255);
+	gdImageFilledRectangle(src, 0, 0, 16, 16, white);
+
+	dst = gdImageCreateTrueColor(50, 50);
+	gdTestAssert(dst != NULL);
+	green = gdImageColorAllocate(dst, 0, 255, 0);
+	gdImageFilledRectangle(dst, 0, 0, 50, 50, green);
+
+	res = gdTransformAffineCopy(dst, 4, 4, src, &rect, matrix);
+	gdTestAssert(res != GD_FALSE);
+
+	status = gdNumFailures();
+	actual_color = gdImageGetPixel(dst, 20, 5);
+	status = (actual_color == expected_color) ? status : 1;
+
+	gdImageDestroy(src);
+	gdImageDestroy(dst);
+	return status;
+}
diff --git a/tests/gif/.gitignore b/tests/gif/.gitignore
index d18444d..d30118f 100644
--- a/tests/gif/.gitignore
+++ b/tests/gif/.gitignore
@@ -5,5 +5,10 @@
 /bug00066
 /bug00181
 /bug00227
+/bug00499
 /gif_im2im
 /gif_null
+/gif_nocolormaps
+/ossfuzz5700
+/php_bug_75571
+/uninitialized_memory_read
diff --git a/tests/gif/CMakeLists.txt b/tests/gif/CMakeLists.txt
index 92010c3..d071874 100644
--- a/tests/gif/CMakeLists.txt
+++ b/tests/gif/CMakeLists.txt
@@ -1,13 +1,23 @@
 LIST(APPEND TESTS_FILES
-	gif_im2im
-	gif_null
-	bug00005
 	bug00005_2
+	bug00181
+	bug00227
+	bug00499
+	gif_null
+	gif_nocolormaps
+	ossfuzz5700
+	php_bug_75571
+	uninitialized_memory_read
 	bug00006
 	bug00060
+	gif_im2im
+)
+
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	bug00005
 	bug00066
-	bug00181
-	bug00227
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/gif/Makemodule.am b/tests/gif/Makemodule.am
index 50f671f..c616b3e 100644
--- a/tests/gif/Makemodule.am
+++ b/tests/gif/Makemodule.am
@@ -2,15 +2,20 @@ libgd_test_programs += \
 	gif/bug00005_2 \
 	gif/bug00181 \
 	gif/bug00227 \
-	gif/gif_null
+	gif/bug00499 \
+	gif/gif_null \
+	gif/gif_nocolormaps \
+	gif/ossfuzz5700 \
+	gif/php_bug_75571 \
+	gif/uninitialized_memory_read \
+	gif/bug00006 \
+	gif/bug00060 \
+	gif/gif_im2im
 
 if HAVE_LIBPNG
 libgd_test_programs += \
 	gif/bug00005 \
-	gif/bug00006 \
-	gif/bug00060 \
-	gif/bug00066 \
-	gif/gif_im2im
+	gif/bug00066
 endif
 
 EXTRA_DIST += \
@@ -22,4 +27,8 @@ EXTRA_DIST += \
 	gif/bug00005_3.gif \
 	gif/bug00060.gif \
 	gif/bug00066.gif \
-	gif/bug00066_exp.png
+	gif/bug00066_exp.png \
+	gif/gif_nocolormaps.gif \
+	gif/ossfuzz5700.gif \
+	gif/php_bug_75571.gif \
+	gif/unitialized_memory_read.gif
diff --git a/tests/gif/bug00006.c b/tests/gif/bug00006.c
index f1a7fe8..95f7620 100644
--- a/tests/gif/bug00006.c
+++ b/tests/gif/bug00006.c
@@ -27,6 +27,10 @@ int main()
 		gdTestErrorMsg("Cannot open <%s> for writing\n", file);
 		return 1;
 	}
+
+	gdImageTrueColorToPaletteSetMethod(im, GD_QUANT_JQUANT, 0);
+	gdImageTrueColorToPalette(im, 1, 256);
+
 	gdImageGif(im,fp);
 	fclose(fp);
 
@@ -60,5 +64,6 @@ int main()
 
 	/* Destroy it */
 	gdImageDestroy(im);
+	free(file);
 	return error;
 }
diff --git a/tests/gif/bug00181.c b/tests/gif/bug00181.c
index 43b9e3b..878537f 100644
--- a/tests/gif/bug00181.c
+++ b/tests/gif/bug00181.c
@@ -92,6 +92,7 @@ int main()
         }
 	error = !im->interlace;
 	gdImageDestroy(im);
+	free(file);
 
 	return error;
 }
diff --git a/tests/gif/bug00227.c b/tests/gif/bug00227.c
index e25bd9a..aa20645 100644
--- a/tests/gif/bug00227.c
+++ b/tests/gif/bug00227.c
@@ -65,5 +65,7 @@ int main()
 	if (buf[PROBE_SIZE-1] & 0x80) return 1;
 	free(buf);
 	fclose(fp);
+
+	free(file);
 	return 0;
 }
diff --git a/tests/gif/bug00499.c b/tests/gif/bug00499.c
new file mode 100644
index 0000000..0fedb92
--- /dev/null
+++ b/tests/gif/bug00499.c
@@ -0,0 +1,51 @@
+/**
+ * Test that adding identical images to GIF animations do no double-free
+ *
+ * We are adding two frames to a GIF animation in gdDisposalNone mode, were the
+ * second frame is identical to the first, which result in that image to have
+ * zero extent.  This program must not cause any memory issues.
+ *
+ * See also <https://github.com/libgd/libgd/issues/499>.
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+    gdImagePtr im;
+    int black;
+    int size;
+    void * res;
+
+    im = gdImageCreate(100, 100);
+    black = gdImageColorAllocate(im, 0, 0, 0);
+    gdImageRectangle(im, 0, 0, 10, 10, black);
+
+    res = gdImageGifAnimBeginPtr(im, &size, 1, 3);
+    if (res != NULL) {
+        gdFree(res);
+    }
+
+    res = gdImageGifAnimAddPtr(im, &size, 0, 0, 0, 100, gdDisposalNone, NULL);
+    if (res != NULL) {
+        gdFree(res);
+    }
+
+    res = gdImageGifAnimAddPtr(im, &size, 0, 0, 0, 100, gdDisposalNone, im);
+    gdTestAssert(res == NULL);
+    if (res != NULL) {
+         gdFree(res);
+    }
+
+    res = gdImageGifAnimEndPtr(&size);
+    if (res != NULL) {
+        gdFree(res);
+    }
+
+    gdImageDestroy(im);
+
+    return gdNumFailures();
+}
diff --git a/tests/gif/gif_nocolormaps.c b/tests/gif/gif_nocolormaps.c
new file mode 100644
index 0000000..4419904
--- /dev/null
+++ b/tests/gif/gif_nocolormaps.c
@@ -0,0 +1,25 @@
+/**
+ * Ensure that a GIF without any Global or Local color tables is still decoded
+ *
+ * GIF89a spec indicates conforming image files need not have Global or Local color tables at all
+ *
+ * See also:	https://www.w3.org/Graphics/GIF/spec-gif89a.txt
+ *		http://probablyprogramming.com/2009/03/15/the-tiniest-gif-ever
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	FILE *fp;
+
+	fp = gdTestFileOpen2("gif", "gif_nocolormaps.gif");
+	gdTestAssert(fp != NULL);
+	im = gdImageCreateFromGif(fp);
+	gdTestAssert(im != NULL);
+	fclose(fp);
+
+	return gdNumFailures();
+}
diff --git a/tests/gif/gif_nocolormaps.gif b/tests/gif/gif_nocolormaps.gif
new file mode 100644
index 0000000..b3aa80d
--- /dev/null
+++ b/tests/gif/gif_nocolormaps.gif
diff --git a/tests/gif/ossfuzz5700.c b/tests/gif/ossfuzz5700.c
new file mode 100644
index 0000000..8fc9f88
--- /dev/null
+++ b/tests/gif/ossfuzz5700.c
@@ -0,0 +1,13 @@
+#include <stdio.h>
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	FILE *fp = gdTestFileOpen("gif/ossfuzz5700.gif");
+	im = gdImageCreateFromGif(fp);
+	fclose(fp);
+	gdImageDestroy(im);
+	return 0;
+}
diff --git a/tests/gif/ossfuzz5700.gif b/tests/gif/ossfuzz5700.gif
new file mode 100644
index 0000000..315c5a8
--- /dev/null
+++ b/tests/gif/ossfuzz5700.gif
diff --git a/tests/gif/php_bug_75571.c b/tests/gif/php_bug_75571.c
new file mode 100644
index 0000000..ec1f37e
--- /dev/null
+++ b/tests/gif/php_bug_75571.c
@@ -0,0 +1,28 @@
+/**
+ * Test that GIF reading does not loop infinitely
+ *
+ * We are reading a crafted GIF image which has been truncated.  This would
+ * trigger an infinite loop formerly, but know bails out early, returning
+ * NULL from gdImageCreateFromGif().
+ *
+ * See also https://bugs.php.net/bug.php?id=75571.
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+    gdImagePtr im;
+    FILE *fp;
+
+    fp = gdTestFileOpen2("gif", "php_bug_75571.gif");
+    gdTestAssert(fp != NULL);
+    im = gdImageCreateFromGif(fp);
+    gdTestAssert(im == NULL);
+    fclose(fp);
+
+    return gdNumFailures();
+}
diff --git a/tests/gif/php_bug_75571.gif b/tests/gif/php_bug_75571.gif
new file mode 100644
index 0000000..3c30b40
--- /dev/null
+++ b/tests/gif/php_bug_75571.gif
diff --git a/tests/gif/uninitialized_memory_read.c b/tests/gif/uninitialized_memory_read.c
new file mode 100644
index 0000000..566fc4a
--- /dev/null
+++ b/tests/gif/uninitialized_memory_read.c
@@ -0,0 +1,42 @@
+/**
+ * Test for uninitialized color map entries
+ *
+ * We're reading a crafted GIF which consists of 16x16 color blocks and which
+ * has only two palette entries in the global color map, but uses other palette
+ * indexes as well. We verify whether all undefined palette indexes produce the
+ * color black.
+ *
+ * See also <CAKm_7a-AO++B6cXYWM_DtycPENG5WNWK7NSEvQ5OmZziMY_JyA@mail.gmail.com>
+ * which had been sent to security@libgd.org.
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+    gdImagePtr im;
+    FILE *fp;
+    int i, j, col;
+
+    fp = gdTestFileOpen2("gif", "unitialized_memory_read.gif");
+    gdTestAssert(fp != NULL);
+    im = gdImageCreateFromGif(fp);
+    gdTestAssert(im != NULL);
+    fclose(fp);
+
+    for (i = 0; i < gdImageSX(im); i += 16) {
+        for (j = 0; j < gdImageSY(im); j += 16) {
+            if (gdImageGetPixel(im, i, j) >= 2) {
+                col = gdImageGetTrueColorPixel(im, i, j);
+                gdTestAssertMsg(col == 0, "(%d,%d): expected color 0, but got %d\n", i, j, col);
+            }
+        }
+    }
+
+    gdImageDestroy(im);
+
+    return gdNumFailures();
+}
diff --git a/tests/gif/unitialized_memory_read.gif b/tests/gif/unitialized_memory_read.gif
new file mode 100644
index 0000000..92fbb7f
--- /dev/null
+++ b/tests/gif/unitialized_memory_read.gif
diff --git a/tests/heif/CMakeLists.txt b/tests/heif/CMakeLists.txt
new file mode 100644
index 0000000..4a41528
--- /dev/null
+++ b/tests/heif/CMakeLists.txt
@@ -0,0 +1,11 @@
+IF(HEIF_FOUND)
+LIST(APPEND TESTS_FILES
+	avif_ptr_double_free
+	heif_im2im
+	heif_null
+	heif_ptr_double_free
+	heif_read
+)
+ENDIF(HEIF_FOUND)
+
+ADD_GD_TESTS()
diff --git a/tests/heif/Makemodule.am b/tests/heif/Makemodule.am
new file mode 100644
index 0000000..8ab60c4
--- /dev/null
+++ b/tests/heif/Makemodule.am
@@ -0,0 +1,12 @@
+if HAVE_LIBHEIF
+libgd_test_programs += \
+	heif/avif_ptr_double_free \
+	heif/heif_im2im \
+	heif/heif_null \
+	heif/heif_ptr_double_free \
+	heif/heif_read
+endif
+
+EXTRA_DIST += \
+	heif/CMakeLists.txt \
+	heif/label.heic
diff --git a/tests/heif/avif_ptr_double_free.c b/tests/heif/avif_ptr_double_free.c
new file mode 100644
index 0000000..f294929
--- /dev/null
+++ b/tests/heif/avif_ptr_double_free.c
@@ -0,0 +1,31 @@
+/**
+ * Test that failure to convert to AVIF returns NULL
+ *
+ * We are creating an image, set its width to zero, and pass this image to
+ * `gdImageAvifPtr()` which is supposed to fail, and as such should return NULL.
+ *
+ * See also <https://github.com/libgd/libgd/issues/381>
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+	gdImagePtr src, dst;
+	int size;
+
+	src = gdImageCreateTrueColor(1, 10);
+	gdTestAssert(src != NULL);
+
+	src->sx = 0;
+
+	dst = gdImageHeifPtrEx(src, &size, 100, GD_HEIF_CODEC_AV1, GD_HEIF_CHROMA_444);
+	gdTestAssert(dst == NULL);
+
+	gdImageDestroy(src);
+
+	return gdNumFailures();
+}
diff --git a/tests/heif/heif_im2im.c b/tests/heif/heif_im2im.c
new file mode 100644
index 0000000..01abf02
--- /dev/null
+++ b/tests/heif/heif_im2im.c
@@ -0,0 +1,57 @@
+/**
+ * Check if it's any difference between the original bitmap and a encoded and
+ * decoded `4:4:4` HEIF lossless image.
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+#include <libheif/heif.h>
+
+int main()
+{
+	gdImagePtr src, dst;
+	int r, g, b;
+	void *p;
+	int size = 0;
+	CuTestImageResult result = {0, 0};
+
+	if (!gdTestAssertMsg(heif_get_version_number_major() == 1 && heif_get_version_number_minor() >= 9, "changing chroma subsampling is not supported in this libheif version\n"))
+		return 77;
+
+	if (!gdTestAssertMsg(heif_have_decoder_for_format(heif_compression_HEVC) && heif_have_encoder_for_format(heif_compression_HEVC), "HEVC codec support missing from libheif\n"))
+		return 77;
+
+	src = gdImageCreateTrueColor(100, 100);
+	gdTestAssertMsg(src != NULL, "could not create src\n");
+	/* libheif seems to have some rounding issues */
+	r = gdImageColorAllocate(src, 0xFE, 0, 0);
+	g = gdImageColorAllocate(src, 0, 0xFE, 0);
+	b = gdImageColorAllocate(src, 0, 0, 0xFE);
+	gdImageFilledRectangle(src, 0, 0, 99, 99, r);
+	gdImageRectangle(src, 20, 20, 79, 79, g);
+	gdImageEllipse(src, 70, 25, 30, 20, b);
+
+	p = gdImageHeifPtrEx(src, &size, 200, GD_HEIF_CODEC_HEVC, GD_HEIF_CHROMA_444);
+	gdTestAssertMsg(p != NULL, "return value of gdImageHeifPtrEx() is null\n");
+	gdTestAssertMsg(size > 0, "gdImageHeifPtrEx() output size is non-positive\n");
+
+	dst = gdImageCreateFromHeifPtr(size, p);
+	gdTestAssertMsg(dst != NULL, "return value of gdImageCreateFromHeifPtr() is null\n");
+
+	if (gdTestAssertMsg(src != NULL && dst != NULL, "cannot compare with NULL buffer"))
+		gdTestImageDiff(src, dst, NULL, &result);
+	else
+		result.pixels_changed = 0;
+	gdTestAssertMsg(result.pixels_changed == 0, "pixels changed: %d\n", result.pixels_changed);
+
+	if (dst != NULL)
+		gdImageDestroy(dst);
+	if (p != NULL)
+		gdFree(p);
+	if (src != NULL)
+		gdImageDestroy(src);
+
+	return gdNumFailures();
+}
diff --git a/tests/heif/heif_null.c b/tests/heif/heif_null.c
new file mode 100644
index 0000000..0b5eac5
--- /dev/null
+++ b/tests/heif/heif_null.c
@@ -0,0 +1,20 @@
+/**
+ * Simple test case that confirms the failure of using `gdImageCreateFromHeif`
+ * with a NULL pointer.
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+
+	im = gdImageCreateFromHeif(NULL);
+	if (!gdTestAssert(im == NULL))
+		gdImageDestroy(im);
+	gdImageHeif(im, NULL); /* noop safely */
+
+	return gdNumFailures();
+}
diff --git a/tests/heif/heif_ptr_double_free.c b/tests/heif/heif_ptr_double_free.c
new file mode 100644
index 0000000..14f1d25
--- /dev/null
+++ b/tests/heif/heif_ptr_double_free.c
@@ -0,0 +1,31 @@
+/**
+ * Test that failure to convert to HEIF returns NULL
+ *
+ * We are creating an image, set its width to zero, and pass this image to
+ * `gdImageHeifPtr()` which is supposed to fail, and as such should return NULL.
+ *
+ * See also <https://github.com/libgd/libgd/issues/381>
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+	gdImagePtr src, dst;
+	int size;
+
+	src = gdImageCreateTrueColor(1, 10);
+	gdTestAssert(src != NULL);
+
+	src->sx = 0;
+
+	dst = gdImageHeifPtrEx(src, &size, 0, GD_HEIF_CODEC_HEVC, GD_HEIF_CHROMA_444);
+	gdTestAssert(dst == NULL);
+
+	gdImageDestroy(src);
+
+	return gdNumFailures();
+}
diff --git a/tests/heif/heif_read.c b/tests/heif/heif_read.c
new file mode 100644
index 0000000..6ecb5f0
--- /dev/null
+++ b/tests/heif/heif_read.c
@@ -0,0 +1,28 @@
+/**
+ * Simple test case that confirms the failure of using `gdImageCreateFromHeif`
+ * with a NULL pointer.
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+#include <libheif/heif.h>
+
+int main()
+{
+	gdImagePtr im;
+	FILE *fp;
+
+	if (!gdTestAssertMsg(heif_have_decoder_for_format(heif_compression_HEVC), "HEVC codec support missing from libheif\n"))
+		return 77;
+
+	fp = gdTestFileOpen2("heif", "label.heic");
+	gdTestAssert(fp != NULL);
+	im = gdImageCreateFromHeif(fp);
+	if (gdTestAssert(im != NULL))
+		gdImageDestroy(im);
+	fclose(fp);
+
+	return gdNumFailures();
+}
diff --git a/tests/heif/label.avif b/tests/heif/label.avif
new file mode 100644
index 0000000..2e84362
--- /dev/null
+++ b/tests/heif/label.avif
diff --git a/tests/heif/label.heic b/tests/heif/label.heic
new file mode 100644
index 0000000..12814f7
--- /dev/null
+++ b/tests/heif/label.heic
diff --git a/tests/jpeg/.gitignore b/tests/jpeg/.gitignore
index 06cc9b2..13bcf04 100644
--- a/tests/jpeg/.gitignore
+++ b/tests/jpeg/.gitignore
@@ -1,6 +1,8 @@
+/bug00338
 /bug_github_18
 /jpeg_empty_file
 /jpeg_im2im
 /jpeg_null
+/jpeg_ptr_double_free
 /jpeg_read
 /jpeg_resolution
diff --git a/tests/jpeg/CMakeLists.txt b/tests/jpeg/CMakeLists.txt
index e8ecf63..ff188a9 100644
--- a/tests/jpeg/CMakeLists.txt
+++ b/tests/jpeg/CMakeLists.txt
@@ -1,12 +1,19 @@
 IF(JPEG_FOUND)
 LIST(APPEND TESTS_FILES
+	jpeg_empty_file
 	jpeg_im2im
+	jpeg_ptr_double_free
 	jpeg_null
-	jpeg_read
-	jpeg_empty_file
 	jpeg_resolution
+)
+
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
 	bug_github_18
+	jpeg_read
+	bug00338
 )
+ENDIF(PNG_FOUND)
 ENDIF(JPEG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/jpeg/Makemodule.am b/tests/jpeg/Makemodule.am
index bc196b1..b778470 100644
--- a/tests/jpeg/Makemodule.am
+++ b/tests/jpeg/Makemodule.am
@@ -1,14 +1,16 @@
 if HAVE_LIBJPEG
 libgd_test_programs += \
-	jpeg/bug_github_18 \
 	jpeg/jpeg_empty_file \
 	jpeg/jpeg_im2im \
-	jpeg/jpeg_null
+	jpeg/jpeg_null \
+	jpeg/jpeg_ptr_double_free \
+	jpeg/jpeg_resolution
 
 if HAVE_LIBPNG
 libgd_test_programs += \
-	jpeg/jpeg_read \
-	jpeg/jpeg_resolution
+	jpeg/bug_github_18 \
+	jpeg/bug00338 \
+	jpeg/jpeg_read
 endif
 endif
 
diff --git a/tests/jpeg/bug00338.c b/tests/jpeg/bug00338.c
new file mode 100644
index 0000000..7874df2
--- /dev/null
+++ b/tests/jpeg/bug00338.c
@@ -0,0 +1,46 @@
+/**
+ * Regression test for <https://github.com/libgd/libgd/issues/338>
+ *
+ * We're testing that reading a JPEG image with gdImageCreateFromJpeg()
+ * raises a GD_WARNING for the fatal libjpeg error, but not a GD_ERROR.
+ * We also make sure, that the fatal libjpeg error is actually reported.
+ *
+ * See also ../png/bug00338.c
+ */
+
+#include <string.h>
+#include "gd.h"
+#include "gd_errors.h"
+#include "gdtest.h"
+
+#define MSG "gd-jpeg: JPEG library reports unrecoverable error: %s"
+
+static int error_handler_called = 0;
+
+static void error_handler(int priority, const char *format, va_list args)
+{
+	if (!strcmp(format, MSG)) {
+		gdTestAssertMsg(priority == GD_WARNING, "expected priority %d, but got %d", GD_WARNING, priority);
+		error_handler_called = 1;
+	}
+}
+
+int main()
+{
+	gdImagePtr im;
+	FILE *fp;
+
+	gdSetErrorMethod(error_handler);
+
+	im = gdImageCreateTrueColor(10, 10);
+	fp = gdTestTempFp();
+	gdImagePng(im, fp);
+	gdImageDestroy(im);
+
+	im = gdImageCreateFromJpeg(fp);
+	gdTestAssert(im == NULL);
+
+	gdTestAssert(error_handler_called);
+
+	return gdNumFailures();
+}
diff --git a/tests/jpeg/jpeg_ptr_double_free.c b/tests/jpeg/jpeg_ptr_double_free.c
new file mode 100644
index 0000000..df5a510
--- /dev/null
+++ b/tests/jpeg/jpeg_ptr_double_free.c
@@ -0,0 +1,31 @@
+/**
+ * Test that failure to convert to JPEG returns NULL
+ *
+ * We are creating an image, set its width to zero, and pass this image to
+ * `gdImageJpegPtr()` which is supposed to fail, and as such should return NULL.
+ *
+ * See also <https://github.com/libgd/libgd/issues/381>
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+    gdImagePtr src, dst;
+    int size;
+
+    src = gdImageCreateTrueColor(1, 10);
+    gdTestAssert(src != NULL);
+
+    src->sx = 0; /* this hack forces gdImageJpegPtr() to fail */
+
+    dst = gdImageJpegPtr(src, &size, 0);
+    gdTestAssert(dst == NULL);
+
+    gdImageDestroy(src);
+
+    return gdNumFailures();
+}
diff --git a/tests/png/.gitignore b/tests/png/.gitignore
index 28eb412..d226591 100644
--- a/tests/png/.gitignore
+++ b/tests/png/.gitignore
@@ -3,6 +3,9 @@
 /bug00086
 /bug00088
 /bug00193
+/bug00338
+/bug00381_1
+/bug00381_2
 /png_im2im
 /png_null
 /png_resolution
diff --git a/tests/png/CMakeLists.txt b/tests/png/CMakeLists.txt
index 228474e..6d618a0 100644
--- a/tests/png/CMakeLists.txt
+++ b/tests/png/CMakeLists.txt
@@ -8,7 +8,15 @@ LIST(APPEND TESTS_FILES
 	bug00086
 	bug00088
 	bug00193
+	bug00338
+	bug00381_1
 )
+
+IF(ENABLE_GD_FORMATS)
+LIST(APPEND TESTS_FILES
+	bug00381_2
+)
+ENDIF(ENABLE_GD_FORMATS)
 ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/png/Makemodule.am b/tests/png/Makemodule.am
index 01c4803..d28253e 100644
--- a/tests/png/Makemodule.am
+++ b/tests/png/Makemodule.am
@@ -5,9 +5,16 @@ libgd_test_programs += \
 	png/bug00086 \
 	png/bug00088 \
 	png/bug00193 \
+	png/bug00338 \
+	png/bug00381_1 \
 	png/png_im2im \
 	png/png_null \
 	png/png_resolution
+
+if ENABLE_GD_FORMATS
+libgd_test_programs += \
+	png/bug00381_2
+endif
 endif
 
 EXTRA_DIST += \
@@ -17,4 +24,5 @@ EXTRA_DIST += \
 	png/bug00088_1_exp.png \
 	png/bug00088_2.png \
 	png/bug00088_2_exp.png \
+	png/bug00381_2.gd \
 	png/emptyfile
diff --git a/tests/png/bug00338.c b/tests/png/bug00338.c
new file mode 100644
index 0000000..f439d8c
--- /dev/null
+++ b/tests/png/bug00338.c
@@ -0,0 +1,44 @@
+/**
+ * Regression test for <https://github.com/libgd/libgd/issues/338>
+ *
+ * We're testing that writing a PNG image with an unsupported quality
+ * raises a GD_WARNING for the fatal libpng error, but not a GD_ERROR.
+ * We also make sure, that the fatal libpng error is actually reported.
+ *
+ * See also ../jpeg/bug00338.c
+ */
+
+#include <string.h>
+#include "gd.h"
+#include "gd_errors.h"
+#include "gdtest.h"
+
+#define MSG "gd-png: fatal libpng error: %s\n"
+
+static int error_handler_called = 0;
+
+static void error_handler(int priority, const char *format, va_list args)
+{
+	if (!strcmp(format, MSG)) {
+		gdTestAssertMsg(priority == GD_WARNING, "expected priority %d, but got %d", GD_WARNING, priority);
+		error_handler_called = 1;
+	}
+}
+
+int main()
+{
+	gdImagePtr im;
+	FILE *fp;
+
+	gdSetErrorMethod(error_handler);
+
+	im = gdImageCreateTrueColor(10, 10);
+	fp = gdTestTempFp();
+	gdImagePngEx(im, fp, 100);
+	gdImageDestroy(im);
+	fclose(fp);
+
+	gdTestAssert(error_handler_called);
+
+	return gdNumFailures();
+}
diff --git a/tests/png/bug00381_1.c b/tests/png/bug00381_1.c
new file mode 100644
index 0000000..d8f375b
--- /dev/null
+++ b/tests/png/bug00381_1.c
@@ -0,0 +1,31 @@
+/**
+ * Test that failure to convert to PNG returns NULL
+ *
+ * We are creating a palette image without allocating any colors in the palette,
+ * and pass this image to `gdImagePngPtr()` which is supposed to fail, and as
+ * such should return NULL.
+ *
+ * See also <https://github.com/libgd/libgd/issues/381>
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+    gdImagePtr im;
+    void *data;
+    int size = 0;
+
+    im = gdImageCreate(100, 100);
+    gdTestAssert(im != NULL);
+
+    data = gdImagePngPtr(im, &size);
+    gdTestAssert(data == NULL);
+
+    gdImageDestroy(im);
+
+    return gdNumFailures();
+}
diff --git a/tests/png/bug00381_2.c b/tests/png/bug00381_2.c
new file mode 100644
index 0000000..84c7bb1
--- /dev/null
+++ b/tests/png/bug00381_2.c
@@ -0,0 +1,35 @@
+/**
+ * Test that failure to convert to PNG returns NULL
+ *
+ * We are reading a palette image without any colors in the palette, and pass
+ * this image to `gdImagePngPtr()` which is supposed to fail, and as such should
+ * return NULL.
+ *
+ * See also <https://github.com/libgd/libgd/issues/381>
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+    gdImagePtr im;
+    FILE *fp;
+    void *data;
+    int size = 0;
+
+    fp = gdTestFileOpen2("png", "bug00381_2.gd");
+    gdTestAssert(fp != NULL);
+    im = gdImageCreateFromGd(fp);
+    gdTestAssert(im != NULL);
+    fclose(fp);
+
+    data = gdImagePngPtr(im, &size);
+    gdTestAssert(data == NULL);
+
+    gdImageDestroy(im);
+
+    return gdNumFailures();
+}
diff --git a/tests/png/bug00381_2.gd b/tests/png/bug00381_2.gd
new file mode 100644
index 0000000..c18480a
--- /dev/null
+++ b/tests/png/bug00381_2.gd
diff --git a/tests/png/png_resolution.c b/tests/png/png_resolution.c
index aed7545..bfc944d 100644
--- a/tests/png/png_resolution.c
+++ b/tests/png/png_resolution.c
@@ -24,7 +24,7 @@ int main()
 		gdImageDestroy(im);
 		return 1;
 	}
-		
+
 	gdImageDestroy(im);
 	return 0;
 }
diff --git a/tests/source/README.md b/tests/source/README.md
new file mode 100644
index 0000000..fce3ac9
--- /dev/null
+++ b/tests/source/README.md
@@ -0,0 +1,3 @@
+These are tests/lints for the source code itself.
+They aren't included in the default `make check` so they aren't run against
+releases, but we run them against Github PRs in Travis.
diff --git a/tests/source/run.sh b/tests/source/run.sh
new file mode 100755
index 0000000..8d7f9c3
--- /dev/null
+++ b/tests/source/run.sh
@@ -0,0 +1,46 @@
+#!/bin/bash -e
+
+if [[ -z "${top_srcdir}" ]] ; then
+	cd "${0%/*}/../.."
+	top_srcdir="${PWD}"
+fi
+TEST_DIR="${top_srcdir}/tests/source"
+
+cd "${top_srcdir}"
+
+ret=0
+
+# Force a basic environment regardless of how we're configured.
+export GIT_PAGER=cat
+export LC_ALL=C
+
+# List all the non-binary files we know about in the tree.
+read -r -d'\n' -a files < <(
+	git ls-tree -r --name-only HEAD | \
+		grep -Ev '\.(avif|bin|bmp|gd|gd2|gif|heic|jpg|jpeg|png|pic|sgi|tga|tiff|ttf|xbm|xpm)$'
+) || :
+
+banner() {
+	echo
+	echo "### $*"
+}
+
+do_grep() {
+	# Use -a so UTF-8 files don't get flagged as binary & skipped.
+	if git grep -aHnE "$@" "${files[@]}" ; then
+		ret=1
+	fi
+}
+
+# Run some tests.
+
+banner "Check for trailing whitespace."
+do_grep '[[:space:]]+$'
+
+banner "Check for Windows line endings."
+do_grep $'\r$'
+
+banner "Checking trailing lines."
+"${TEST_DIR}"/whitespace.py "${files[@]}"
+
+exit ${ret}
diff --git a/tests/source/whitespace.py b/tests/source/whitespace.py
new file mode 100755
index 0000000..2d979fd
--- /dev/null
+++ b/tests/source/whitespace.py
@@ -0,0 +1,52 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+"""Helper for checking whitespace.
+
+These operations aren't easy to do in pure shell.
+"""
+
+from __future__ import print_function
+
+import sys
+
+
+def check(path):
+    with open(path, 'rb') as fp:
+        # Skip 0 byte files.
+        first_byte = fp.read(1)
+        if not first_byte:
+            return 0
+
+        # Check for leading blank lines.
+        if b'\n' == first_byte:
+            print('%s: trim leading blank lines' % (path,), file=sys.stderr)
+            return 1
+
+        # Check for missing trailing new line.
+        fp.seek(-1, 2)
+        if b'\n' != fp.read(1):
+            print('%s: missing trailing new line' % (path,), file=sys.stderr)
+            return 1
+        elif fp.tell() == 1:
+            print('%s: dummy file' % (path,), file=sys.stderr)
+            return 1
+
+        # Check for trailing blank lines.
+        fp.seek(-2, 2)
+        if b'\n\n' == fp.read(2):
+            print('%s: trim trailing blank lines' % (path,), file=sys.stderr)
+            return 1
+
+    return 0
+
+
+def main(argv):
+    ret = 0
+    for path in argv:
+        ret |= check(path)
+    return ret
+
+
+if __name__ == '__main__':
+    sys.exit(main(sys.argv[1:]))
diff --git a/tests/tga/.gitignore b/tests/tga/.gitignore
index 7a659b1..cf0556b 100644
--- a/tests/tga/.gitignore
+++ b/tests/tga/.gitignore
@@ -3,5 +3,6 @@
 /bug00247a
 /bug00248
 /bug00248a
+/heap_overflow
 /tga_null
 /tga_read
diff --git a/tests/tga/CMakeLists.txt b/tests/tga/CMakeLists.txt
index 789fb14..ca191a6 100644
--- a/tests/tga/CMakeLists.txt
+++ b/tests/tga/CMakeLists.txt
@@ -1,11 +1,17 @@
 LIST(APPEND TESTS_FILES
-	tga_null
 	bug00084
 	bug00247
 	bug00247a
 	bug00248
 	bug00248a
+	heap_overflow
+	tga_null
+)
+
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
 	tga_read
 )
+ENDIF(PNG_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/tga/Makemodule.am b/tests/tga/Makemodule.am
index a1e6af6..091e3be 100644
--- a/tests/tga/Makemodule.am
+++ b/tests/tga/Makemodule.am
@@ -4,8 +4,13 @@ libgd_test_programs += \
 	tga/bug00247a \
 	tga/bug00248 \
 	tga/bug00248a \
-	tga/tga_null \
+	tga/heap_overflow \
+	tga/tga_null
+
+if HAVE_LIBPNG
+libgd_test_programs += \
 	tga/tga_read
+endif
 
 EXTRA_DIST += \
 	tga/CMakeLists.txt \
@@ -14,6 +19,8 @@ EXTRA_DIST += \
 	tga/bug00247a.tga \
 	tga/bug00248.tga \
 	tga/bug00248a.tga \
+	tga/heap_overflow_1.tga \
+	tga/heap_overflow_2.tga \
 	tga/tga_read_rgb.png \
 	tga/tga_read_rgb.tga \
 	tga/tga_read_rgb_rle.tga
diff --git a/tests/tga/heap_overflow.c b/tests/tga/heap_overflow.c
new file mode 100644
index 0000000..ddd4b63
--- /dev/null
+++ b/tests/tga/heap_overflow.c
@@ -0,0 +1,59 @@
+/**
+ * Test that crafted TGA files don't trigger OOB reads.
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+static void check_file(char *basename);
+static size_t read_test_file(char **buffer, char *basename);
+
+
+int main()
+{
+    check_file("heap_overflow_1.tga");
+    check_file("heap_overflow_2.tga");
+
+    return gdNumFailures();
+}
+
+
+static void check_file(char *basename)
+{
+    gdImagePtr im;
+    char *buffer;
+    size_t size;
+
+    size = read_test_file(&buffer, basename);
+    im = gdImageCreateFromTgaPtr(size, (void *) buffer);
+    gdTestAssert(im == NULL);
+    free(buffer);
+}
+
+
+static size_t read_test_file(char **buffer, char *basename)
+{
+    char *filename;
+    FILE *fp;
+    size_t exp_size, act_size;
+
+    filename = gdTestFilePath2("tga", basename);
+    fp = fopen(filename, "rb");
+    gdTestAssert(fp != NULL);
+
+	fseek(fp, 0, SEEK_END);
+	exp_size = ftell(fp);
+	fseek(fp, 0, SEEK_SET);
+
+    *buffer = malloc(exp_size);
+    gdTestAssert(*buffer != NULL);
+    act_size = fread(*buffer, sizeof(**buffer), exp_size, fp);
+    gdTestAssert(act_size == exp_size);
+
+    fclose(fp);
+    free(filename);
+
+    return act_size;
+}
diff --git a/tests/tga/heap_overflow.tga b/tests/tga/heap_overflow.tga
new file mode 100644
index 0000000..e9bc0ec
--- /dev/null
+++ b/tests/tga/heap_overflow.tga
diff --git a/tests/tga/heap_overflow_1.tga b/tests/tga/heap_overflow_1.tga
new file mode 100644
index 0000000..e9bc0ec
--- /dev/null
+++ b/tests/tga/heap_overflow_1.tga
diff --git a/tests/tga/heap_overflow_2.tga b/tests/tga/heap_overflow_2.tga
new file mode 100644
index 0000000..2b681f2
--- /dev/null
+++ b/tests/tga/heap_overflow_2.tga
diff --git a/tests/tiff/.gitignore b/tests/tiff/.gitignore
index 7cf35ee..5f4eb55 100644
--- a/tests/tiff/.gitignore
+++ b/tests/tiff/.gitignore
@@ -1,3 +1,5 @@
 /tiff_dpi
 /tiff_im2im
 /tiff_null
+/tiff_invalid_read
+/tiff_read_bw
diff --git a/tests/tiff/CMakeLists.txt b/tests/tiff/CMakeLists.txt
index 03f630c..b1ce8a8 100644
--- a/tests/tiff/CMakeLists.txt
+++ b/tests/tiff/CMakeLists.txt
@@ -1,9 +1,16 @@
 IF(TIFF_FOUND)
 LIST(APPEND TESTS_FILES
 	tiff_im2im
+	tiff_invalid_read
 	tiff_null
 	tiff_dpi
 )
+
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	tiff_read_bw
+)
+ENDIF(PNG_FOUND)
 ENDIF(TIFF_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/tiff/Makemodule.am b/tests/tiff/Makemodule.am
index fd39699..a136439 100644
--- a/tests/tiff/Makemodule.am
+++ b/tests/tiff/Makemodule.am
@@ -2,8 +2,19 @@ if HAVE_LIBTIFF
 libgd_test_programs += \
 	tiff/tiff_dpi \
 	tiff/tiff_im2im \
+	tiff/tiff_invalid_read \
 	tiff/tiff_null
+
+if HAVE_LIBPNG
+libgd_test_programs += \
+	tiff/tiff_read_bw
+endif
 endif
 
 EXTRA_DIST += \
-	tiff/CMakeLists.txt
+	tiff/CMakeLists.txt \
+	tiff/tiff_invalid_read_1.tiff \
+	tiff/tiff_invalid_read_2.tiff \
+	tiff/tiff_invalid_read_3.tiff \
+	tiff/tiff_read_bw.tiff \
+	tiff/tiff_read_bw_exp.png
diff --git a/tests/tiff/tiff_dpi.c b/tests/tiff/tiff_dpi.c
index d639839..7362646 100644
--- a/tests/tiff/tiff_dpi.c
+++ b/tests/tiff/tiff_dpi.c
@@ -1,16 +1,9 @@
-/* 
+/*
  * Test that reading and writing image resolution values to/from TIFF files
  * works correctly.  Set the image resolution, write the file, read the file
  * back and test that the image resolution comes back correct.
  */
-#ifdef _WIN32
-#include <stdio.h>
-int main()
-{
-	printf("skip");
-	return 0;
-}
-#else
+
 #include "gd.h"
 #include "gdtest.h"
 
@@ -30,7 +23,7 @@ int main()
 	r = gdImageColorAllocate(src, 0xFF, 0, 0);
 	gdImageFilledRectangle(src, 0, 0, 99, 99, r);
 
-	// gd default DPI is 96; libtiff default is 72.  
+	// gd default DPI is 96; libtiff default is 72.
 	// Use something else so we know the value has been
 	// written / read correctly.
 	res_x = 100;
@@ -81,4 +74,3 @@ door0:
 	gdImageDestroy(src);
 	return status;
 }
-#endif
diff --git a/tests/tiff/tiff_im2im.c b/tests/tiff/tiff_im2im.c
index b6b240e..7b6c4cb 100644
--- a/tests/tiff/tiff_im2im.c
+++ b/tests/tiff/tiff_im2im.c
@@ -1,11 +1,3 @@
-#ifdef _WIN32
-#include <stdio.h>
-int main()
-{
-	printf("skip");
-	return 0;
-}
-#else
 #include "gd.h"
 #include "gdtest.h"
 
@@ -70,4 +62,3 @@ door0:
 	gdImageDestroy(src);
 	return status;
 }
-#endif
\ No newline at end of file
diff --git a/tests/tiff/tiff_invalid_read.c b/tests/tiff/tiff_invalid_read.c
new file mode 100644
index 0000000..bed5389
--- /dev/null
+++ b/tests/tiff/tiff_invalid_read.c
@@ -0,0 +1,61 @@
+/*
+We're testing that reading corrupt TIFF files doesn't cause any memory issues,
+and that the operation gracefully fails (i.e. gdImageCreateFromTiffPtr() returns
+NULL).
+*/
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+static void check_file(char *basename);
+static size_t read_test_file(char **buffer, char *basename);
+
+
+int main()
+{
+    check_file("tiff_invalid_read_1.tiff");
+    check_file("tiff_invalid_read_2.tiff");
+    check_file("tiff_invalid_read_3.tiff");
+
+    return gdNumFailures();
+}
+
+
+static void check_file(char *basename)
+{
+    gdImagePtr im;
+    char *buffer;
+    size_t size;
+
+    size = read_test_file(&buffer, basename);
+    im = gdImageCreateFromTiffPtr(size, (void *) buffer);
+    gdTestAssert(im == NULL);
+    free(buffer);
+}
+
+
+static size_t read_test_file(char **buffer, char *basename)
+{
+    char *filename;
+    FILE *fp;
+    size_t exp_size, act_size;
+
+    filename = gdTestFilePath2("tiff", basename);
+    fp = fopen(filename, "rb");
+    gdTestAssert(fp != NULL);
+
+	fseek(fp, 0, SEEK_END);
+	exp_size = ftell(fp);
+	fseek(fp, 0, SEEK_SET);
+
+    *buffer = malloc(exp_size);
+    gdTestAssert(*buffer != NULL);
+    act_size = fread(*buffer, sizeof(**buffer), exp_size, fp);
+    gdTestAssert(act_size == exp_size);
+
+    fclose(fp);
+    free(filename);
+
+    return act_size;
+}
diff --git a/tests/tiff/tiff_invalid_read_1.tiff b/tests/tiff/tiff_invalid_read_1.tiff
new file mode 100644
index 0000000..b3877e3
--- /dev/null
+++ b/tests/tiff/tiff_invalid_read_1.tiff
diff --git a/tests/tiff/tiff_invalid_read_2.tiff b/tests/tiff/tiff_invalid_read_2.tiff
new file mode 100644
index 0000000..f9967e5
--- /dev/null
+++ b/tests/tiff/tiff_invalid_read_2.tiff
diff --git a/tests/tiff/tiff_invalid_read_3.tiff b/tests/tiff/tiff_invalid_read_3.tiff
new file mode 100644
index 0000000..67ca2a7
--- /dev/null
+++ b/tests/tiff/tiff_invalid_read_3.tiff
diff --git a/tests/tiff/tiff_null.c b/tests/tiff/tiff_null.c
index 19b64f7..ccaade7 100644
--- a/tests/tiff/tiff_null.c
+++ b/tests/tiff/tiff_null.c
@@ -1,11 +1,3 @@
-#ifdef _WIN32
-#include <stdio.h>
-int main()
-{
-	printf("skip");
-	return 0;
-}
-#else
 #include "gd.h"
 
 int main()
@@ -20,4 +12,3 @@ int main()
 	gdImageTiff(im, NULL); /* noop safely */
 	return 0;
 }
-#endif
\ No newline at end of file
diff --git a/tests/tiff/tiff_read_bw.c b/tests/tiff/tiff_read_bw.c
new file mode 100644
index 0000000..93b646d
--- /dev/null
+++ b/tests/tiff/tiff_read_bw.c
@@ -0,0 +1,25 @@
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	FILE *fp;
+	char *path;
+
+	fp = gdTestFileOpen2("tiff", "tiff_read_bw.tiff");
+	gdTestAssert(fp != NULL);
+	im = gdImageCreateFromTiff(fp);
+	fclose(fp);
+
+	gdTestAssert(im != NULL);
+	gdTestAssert(!gdImageTrueColor(im));
+
+	path = gdTestFilePath2("tiff", "tiff_read_bw_exp.png");
+	gdAssertImageEqualsToFile(path, im);
+	gdFree(path);
+
+	gdImageDestroy(im);
+
+	return gdNumFailures();
+}
diff --git a/tests/tiff/tiff_read_bw.tiff b/tests/tiff/tiff_read_bw.tiff
new file mode 100644
index 0000000..69813f0
--- /dev/null
+++ b/tests/tiff/tiff_read_bw.tiff
diff --git a/tests/tiff/tiff_read_bw_exp.png b/tests/tiff/tiff_read_bw_exp.png
new file mode 100644
index 0000000..b43daf9
--- /dev/null
+++ b/tests/tiff/tiff_read_bw_exp.png
diff --git a/tests/wbmp/CMakeLists.txt b/tests/wbmp/CMakeLists.txt
index 787227c..4ec45bd 100644
--- a/tests/wbmp/CMakeLists.txt
+++ b/tests/wbmp/CMakeLists.txt
@@ -1,6 +1,6 @@
 LIST(APPEND TESTS_FILES
-	wbmp_im2im
 	wbmp_null
+	wbmp_im2im
 )
 
 ADD_GD_TESTS()
diff --git a/tests/wbmp/Makemodule.am b/tests/wbmp/Makemodule.am
index fb12272..37f09e1 100644
--- a/tests/wbmp/Makemodule.am
+++ b/tests/wbmp/Makemodule.am
@@ -1,10 +1,6 @@
 libgd_test_programs += \
-	wbmp/wbmp_null
-
-if HAVE_LIBPNG
-libgd_test_programs += \
+	wbmp/wbmp_null \
 	wbmp/wbmp_im2im
-endif
 
 EXTRA_DIST += \
 	wbmp/CMakeLists.txt
diff --git a/tests/webp/.gitignore b/tests/webp/.gitignore
index f5816bc..b167630 100644
--- a/tests/webp/.gitignore
+++ b/tests/webp/.gitignore
@@ -1,2 +1,4 @@
 /bug00111
+/bug_double_free
 /webp_ll_im2im
+/gdImageWebpEx
diff --git a/tests/webp/CMakeLists.txt b/tests/webp/CMakeLists.txt
index e114f80..6a4431c 100644
--- a/tests/webp/CMakeLists.txt
+++ b/tests/webp/CMakeLists.txt
@@ -1,8 +1,14 @@
 IF(WEBP_FOUND)
 LIST(APPEND TESTS_FILES
 	bug00111
+	gdImageWebpEx
 	webp_ll_im2im
 )
+IF(JPEG_FOUND)
+LIST(APPEND TESTS_FILES
+	bug_double_free
+)
+ENDIF(JPEG_FOUND)
 ENDIF(WEBP_FOUND)
 
 ADD_GD_TESTS()
diff --git a/tests/webp/Makemodule.am b/tests/webp/Makemodule.am
index 741e8f2..c6c9528 100644
--- a/tests/webp/Makemodule.am
+++ b/tests/webp/Makemodule.am
@@ -1,8 +1,14 @@
 if HAVE_LIBWEBP
 libgd_test_programs += \
 	webp/bug00111 \
+	webp/gdImageWebpEx \
 	webp/webp_ll_im2im
+if HAVE_LIBJPEG
+libgd_test_programs += \
+	webp/bug_double_free
+endif
 endif
 
 EXTRA_DIST += \
-	webp/CMakeLists.txt
+	webp/CMakeLists.txt \
+	webp/bug_double_free.jpg
diff --git a/tests/webp/bug_double_free.c b/tests/webp/bug_double_free.c
new file mode 100644
index 0000000..43eecec
--- /dev/null
+++ b/tests/webp/bug_double_free.c
@@ -0,0 +1,29 @@
+/**
+ * Test that a too large image doesn't trigger an double-free when written
+ * to memory.
+ */
+
+
+#include "gd.h"
+#include "gdtest.h"
+
+
+int main()
+{
+    gdImagePtr im1, im2;
+    FILE *fp;
+    int size;
+
+    fp = gdTestFileOpen2("webp", "bug_double_free.jpg");
+    gdTestAssert(fp != NULL);
+    im1 = gdImageCreateFromJpeg(fp);
+    gdTestAssert(im1 != NULL);
+    fclose(fp);
+
+    im2 = gdImageWebpPtr(im1, &size);
+    gdTestAssert(im2 == NULL);
+
+    gdImageDestroy(im1);
+
+    return gdNumFailures();
+}
diff --git a/tests/webp/bug_double_free.jpg b/tests/webp/bug_double_free.jpg
new file mode 100644
index 0000000..9b792fb
--- /dev/null
+++ b/tests/webp/bug_double_free.jpg
diff --git a/tests/webp/gdImageWebpEx.c b/tests/webp/gdImageWebpEx.c
new file mode 100644
index 0000000..43011de
--- /dev/null
+++ b/tests/webp/gdImageWebpEx.c
@@ -0,0 +1,26 @@
+/**
+ * Basic testcase for gdImageWebpEx()
+ **/
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	FILE *fp1;
+	int size = 1;
+
+	im = gdImageCreateTrueColor(20, 20);
+	if (!im) {
+		return 1;
+	}
+
+	fp1 = gdTestTempFp();
+	gdImageWebpEx(im, fp1, 8);
+	gdImageWebpPtrEx(im, &size, 9);
+
+	fclose(fp1);
+
+	gdImageDestroy(im);
+	return 0;
+}
diff --git a/tests/xbm/.gitignore b/tests/xbm/.gitignore
index 313d503..8a2565a 100644
--- a/tests/xbm/.gitignore
+++ b/tests/xbm/.gitignore
@@ -1 +1,4 @@
+/github_bug_109
 /github_bug_170
+/github_bug_501
+/x10_basic_read
diff --git a/tests/xbm/CMakeLists.txt b/tests/xbm/CMakeLists.txt
index 183cf5e..2447fd5 100644
--- a/tests/xbm/CMakeLists.txt
+++ b/tests/xbm/CMakeLists.txt
@@ -1,5 +1,13 @@
 LIST(APPEND TESTS_FILES
+	github_bug_501
 	github_bug_170
 )
 
+IF(PNG_FOUND)
+LIST(APPEND TESTS_FILES
+	github_bug_109
+	x10_basic_read
+)
+ENDIF(PNG_FOUND)
+
 ADD_GD_TESTS()
diff --git a/tests/xbm/Makemodule.am b/tests/xbm/Makemodule.am
index ba1eabd..4d14916 100644
--- a/tests/xbm/Makemodule.am
+++ b/tests/xbm/Makemodule.am
@@ -1,5 +1,17 @@
 libgd_test_programs += \
+	xbm/github_bug_501 \
 	xbm/github_bug_170
 
+if HAVE_LIBPNG
+libgd_test_programs += \
+	xbm/github_bug_109 \
+	xbm/x10_basic_read
+endif
+
 EXTRA_DIST += \
-	xbm/CMakeLists.txt
+	xbm/CMakeLists.txt \
+	xbm/github_bug_109.xbm \
+	xbm/github_bug_109_exp.png \
+	xbm/x10_basic_read.xbm \
+	xbm/x10_basic_read_exp.png \
+	xbm/github_bug_501.xbm
diff --git a/tests/xbm/github_bug_109.c b/tests/xbm/github_bug_109.c
new file mode 100644
index 0000000..70b7937
--- /dev/null
+++ b/tests/xbm/github_bug_109.c
@@ -0,0 +1,33 @@
+/**
+ * Test reading of XBM images with a width that is not a multiple of 8
+ *
+ * We're reading such an XBM image, and check that we got what we've expected,
+ * instead of an error message.
+ *
+ * See also <https://github.com/libgd/libgd/issues/109>.
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	FILE *fp;
+	char *path;
+
+	fp = gdTestFileOpen2("xbm", "github_bug_109.xbm");
+	im = gdImageCreateFromXbm(fp);
+	fclose(fp);
+	gdTestAssert(im != NULL);
+	gdTestAssert(gdImageGetTrueColorPixel(im, 0, 0) == 0);
+	gdTestAssert(gdImageGetTrueColorPixel(im, 0, 1) == 0xffffff);
+
+	path = gdTestFilePath2("xbm", "github_bug_109_exp.png");
+	gdAssertImageEqualsToFile(path, im);
+	gdFree(path);
+
+	gdImageDestroy(im);
+
+	return gdNumFailures();
+}
diff --git a/tests/xbm/github_bug_109.xbm b/tests/xbm/github_bug_109.xbm
new file mode 100644
index 0000000..f427d86
--- /dev/null
+++ b/tests/xbm/github_bug_109.xbm
@@ -0,0 +1,5 @@
+#define test_width 10
+#define test_height 10
+static unsigned char test_bits[] = {
+  0xFF, 0x03, 0x00, 0x00, 0xFF, 0x03, 0x00, 0x00, 0xFF, 0x03, 0x00, 0x00, 
+  0xFF, 0x03, 0x00, 0x00, 0xFF, 0x03, 0x00, 0x00};
diff --git a/tests/xbm/github_bug_109_exp.png b/tests/xbm/github_bug_109_exp.png
new file mode 100644
index 0000000..505b545
--- /dev/null
+++ b/tests/xbm/github_bug_109_exp.png
diff --git a/tests/xbm/github_bug_170.c b/tests/xbm/github_bug_170.c
index 3900da7..8134fb8 100644
--- a/tests/xbm/github_bug_170.c
+++ b/tests/xbm/github_bug_170.c
@@ -47,4 +47,4 @@ int main()
 	gdTestAssertMsg(length == 250, "expected to write 250 bytes; %jd bytes written", (intmax_t) length);
 	return gdNumFailures();
 }
-#endif
\ No newline at end of file
+#endif
diff --git a/tests/xbm/github_bug_501.c b/tests/xbm/github_bug_501.c
new file mode 100644
index 0000000..5d8bfd7
--- /dev/null
+++ b/tests/xbm/github_bug_501.c
@@ -0,0 +1,39 @@
+/*
+	Test reading an invalid XBM image.
+
+	The pixels of the XBM image are invalid hex which makes the uninitialezed
+	variable be encoded into the output image i.e. information disclosure.
+	The image is 8*2.
+
+	See also <https://github.com/libgd/libgd/issues/501>.
+*/
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+
+	gdImagePtr im;
+	FILE *fp;
+
+	fp = gdTestFileOpen2("xbm", "github_bug_501.xbm");
+	im = gdImageCreateFromXbm(fp);
+
+	gdTestAssert(im == NULL);
+
+	if (im) {
+		gdTestErrorMsg("Info Disclosed\n");
+		int i;
+		for (i = 0; i < 8; i++) {
+			printf("Pixel(%d, 0) %0x\n", i, gdImageGetPixel(im, i, 0));
+		}
+		for (i = 0; i < 8; i++) {
+			printf("Pixel(%d, 1) %0x\n", i, gdImageGetPixel(im, i, 1));
+		}
+		gdImageDestroy(im);
+	}
+
+	fclose(fp);
+	return gdNumFailures();
+}
diff --git a/tests/xbm/github_bug_501.xbm b/tests/xbm/github_bug_501.xbm
new file mode 100644
index 0000000..41ad301
--- /dev/null
+++ b/tests/xbm/github_bug_501.xbm
@@ -0,0 +1,4 @@
+#define width 8
+#define height 2
+static char bits[] ={
+xzzxzz
diff --git a/tests/xbm/x10_basic_read.c b/tests/xbm/x10_basic_read.c
new file mode 100644
index 0000000..f7c505e
--- /dev/null
+++ b/tests/xbm/x10_basic_read.c
@@ -0,0 +1,30 @@
+/**
+ * Test reading of an X10 style XBM file
+ *
+ * X10 style XBMs define a short[] instead of a char[] array. We're testing
+ * that such files are read correctly, particularly regarding the line padding,
+ * which is 2 bytes instead of 1, and the endianess.
+ */
+
+#include "gd.h"
+#include "gdtest.h"
+
+int main()
+{
+	gdImagePtr im;
+	FILE *fp;
+	char *path;
+
+	fp = gdTestFileOpen2("xbm", "x10_basic_read.xbm");
+	im = gdImageCreateFromXbm(fp);
+	fclose(fp);
+	gdTestAssert(im != NULL);
+
+	path = gdTestFilePath2("xbm", "x10_basic_read_exp.png");
+	gdAssertImageEqualsToFile(path, im);
+	gdFree(path);
+
+	gdImageDestroy(im);
+
+	return gdNumFailures();
+}
diff --git a/tests/xbm/x10_basic_read.xbm b/tests/xbm/x10_basic_read.xbm
new file mode 100644
index 0000000..d8ca2cd
--- /dev/null
+++ b/tests/xbm/x10_basic_read.xbm
@@ -0,0 +1,4 @@
+#define x10_basic_read_width 17
+#define x10_basic_read_height 3
+static unsigned short x10_basic_read_bits[] = {
+  0xFFFF, 0x0001, 0x0000, 0x0000, 0xFFFF, 0x0001};
diff --git a/tests/xbm/x10_basic_read_exp.png b/tests/xbm/x10_basic_read_exp.png
new file mode 100644
index 0000000..fbcdf0c
--- /dev/null
+++ b/tests/xbm/x10_basic_read_exp.png