1 files changed, 117 insertions, 0 deletions
diff --git a/tools/gslite/gslt_image.c b/tools/gslite/gslt_image.c
new file mode 100644
index 000000000..09f463f76
--- /dev/null
+++ b/tools/gslite/gslt_image.c
@@ -0,0 +1,117 @@
+/* Copyright (C) 2006 artofcode LLC.
+   All Rights Reserved.
+
+   This software is provided AS-IS with no warranty, either express or
+   implied.
+
+   This software is distributed under license and may not be copied, modified
+   or distributed except as expressly authorized under the terms of that
+   license.  Refer to licensing information at http://www.artifex.com/
+   or contact Artifex Software, Inc.,  7 Mt. Lassen Drive - Suite A-134,
+   San Rafael, CA  94903, U.S.A., +1(415)492-9861, for further information.
+*/
+
+/* $Id: gslt_image.c 2991 2007-12-18 23:05:58Z giles $ */
+/* gslt image loading implementation */
+
+#include "memory_.h"
+#include "gsmemory.h"
+#include "gp.h"
+#include "gslt_image.h"
+#include "ctype_.h"
+#include "strimpl.h"
+#include "scommon.h"
+#include "jpeglib_.h"           /* for jpeg filter */
+#include "sdct.h"
+#include "sjpeg.h"
+#include "gdebug.h"
+#include "gsutil.h"
+#include "gserror.h"
+
+/* gs memory management structure descriptor for gslt_image_t */
+/* normally this would be in the header with the structure
+   declaration, with which is must be synchronized, but we
+   wish to hide such details from the client */
+#define public_st_gslt_image() \
+  gs_public_st_ptrs1(st_gslt_image, gslt_image_t,\
+        "gslt_image_t", gslt_image_enum_ptrs, gslt_image_reloc_ptrs,\
+        samples)
+
+/* define the gslt_image_t structure descriptor */
+public_st_gslt_image();
+
+
+/*
+ * Strip alpha channel from an image
+ * assumes a collapsed stride
+ */
+static void 
+gslt_strip_alpha(gslt_image_t *image)
+{
+    gslt_image_colorspace cs = image->colorspace;
+    int n = image->components;
+    int y, x, k;
+    byte *sp, *dp;
+
+    if (image->bits != 8)
+    {
+        gs_warn1("cannot strip alpha from %dbpc images", image->bits);
+        return;
+    }
+
+    if ((cs != GSLT_GRAY_A) && (cs != GSLT_RGB_A) && (cs != GSLT_CMYK_A))
+        return;
+
+    for (y = 0; y < image->height; y++)
+    {
+        sp = image->samples + image->width * n * y;
+        dp = image->samples + image->width * (n - 1) * y;
+        for (x = 0; x < image->width; x++)
+        {
+            for (k = 0; k < n - 1; k++)
+                *dp++ = *sp++;
+            sp++;
+        }
+    }
+
+    image->colorspace --; /* assume foo_A follows foo */
+    image->components --;
+    image->stride = (n - 1) * image->width;
+}
+
+/*
+ * Switch on file magic to decode an image.
+ */
+gslt_image_t *
+gslt_image_decode(gs_memory_t *mem, byte *buf, int len)
+{
+    gslt_image_t *image = NULL;
+    int error = gs_okay;
+
+    if (buf[0] == 0xff && buf[1] == 0xd8)
+        image = gslt_image_decode_jpeg(mem, buf, len);
+    else if (memcmp(buf, "\211PNG\r\n\032\n", 8) == 0)
+        image = gslt_image_decode_png(mem, buf, len);
+    else if (memcmp(buf, "MM", 2) == 0)
+        image = gslt_image_decode_tiff(mem, buf, len);
+    else if (memcmp(buf, "II", 2) == 0)
+        image = gslt_image_decode_tiff(mem, buf, len);
+    else
+        error = gs_throw(-1, "unknown image file format");
+
+    if (image == NULL)
+        error = gs_rethrow(error, "could not decode image");
+
+    return image;
+}
+
+void
+gslt_image_free(gs_memory_t *mem, gslt_image_t *image)
+{
+    if (image != NULL) {
+	if (image->samples) {
+	    gs_free_object(mem, image->samples, "free gslt_image samples");
+	}
+	gs_free_object(mem, image, "free gslt_image");
+    }
+}