Add support for reading monochromatic floating point formats

It seems the builtin converting reader doesn't support all formats.

Change-Id: Ia24b4d017476e2dd806861c3e98f3df19dce4584
Fixes: QTBUG-112947
Reviewed-by: Eirik Aavitsland <eirik.aavitsland@qt.io>

2 files changed, 52 insertions, 8 deletions

diff --git a/src/plugins/imageformats/tiff/qtiffhandler.cpp b/src/plugins/imageformats/tiff/qtiffhandler.cpp
index d01e888..aadf134 100644
--- a/src/plugins/imageformats/tiff/qtiffhandler.cpp
+++ b/src/plugins/imageformats/tiff/qtiffhandler.cpp
@@ -277,9 +277,9 @@ bool QTiffHandlerPrivate::readHeaders(QIODevice *device)
     else if ((grayscale || photometric == PHOTOMETRIC_PALETTE) && bitPerSample == 8 && samplesPerPixel == 1)
         format = QImage::Format_Indexed8;
     else if (samplesPerPixel < 4)
-        if (bitPerSample == 16 && photometric == PHOTOMETRIC_RGB)
+        if (bitPerSample == 16 && (photometric == PHOTOMETRIC_RGB || photometric == PHOTOMETRIC_MINISBLACK))
             format = floatingPoint ? QImage::Format_RGBX16FPx4 : QImage::Format_RGBX64;
-        else if (bitPerSample == 32 && floatingPoint && photometric == PHOTOMETRIC_RGB)
+        else if (bitPerSample == 32 && floatingPoint && (photometric == PHOTOMETRIC_RGB || photometric == PHOTOMETRIC_MINISBLACK))
             format = QImage::Format_RGBX32FPx4;
         else
             format = QImage::Format_RGB32;
@@ -419,9 +419,9 @@ bool QTiffHandler::read(QImage *image)
     if (format8bit || format16bit || format64bit || format64fp || format128fp) {
         int bytesPerPixel = image->depth() / 8;
         if (format == QImage::Format_RGBX64 || format == QImage::Format_RGBX16FPx4)
-            bytesPerPixel = 6;
+            bytesPerPixel = d->photometric == PHOTOMETRIC_RGB ? 6 : 2;
         else if (format == QImage::Format_RGBX32FPx4)
-            bytesPerPixel = 12;
+            bytesPerPixel = d->photometric == PHOTOMETRIC_RGB ? 12 : 4;
         if (TIFFIsTiled(tiff)) {
             quint32 tileWidth, tileLength;
             TIFFGetField(tiff, TIFFTAG_TILEWIDTH, &tileWidth);
@@ -470,10 +470,17 @@ bool QTiffHandler::read(QImage *image)
                 }
             }
         }
-        if (format == QImage::Format_RGBX64 || format == QImage::Format_RGBX16FPx4)
-            rgb48fixup(image, d->floatingPoint);
-        else if (format == QImage::Format_RGBX32FPx4)
-            rgb96fixup(image);
+        if (format == QImage::Format_RGBX64 || format == QImage::Format_RGBX16FPx4) {
+            if (d->photometric == PHOTOMETRIC_RGB)
+                rgb48fixup(image, d->floatingPoint);
+            else
+                rgbFixup(image);
+        } else if (format == QImage::Format_RGBX32FPx4) {
+            if (d->photometric == PHOTOMETRIC_RGB)
+                rgb96fixup(image);
+            else
+                rgbFixup(image);
+        }
     } else {
         const int stopOnError = 1;
         if (TIFFReadRGBAImageOriented(tiff, width, height, reinterpret_cast<uint32_t *>(image->bits()), qt2Exif(d->transformation), stopOnError)) {
@@ -1016,6 +1023,42 @@ void QTiffHandler::rgb96fixup(QImage *image)
     }
 }
 
+void QTiffHandler::rgbFixup(QImage *image)
+{
+    Q_ASSERT(d->floatingPoint);
+    if (image->depth() == 64) {
+        const int h = image->height();
+        const int w = image->width();
+        uchar *scanline = image->bits();
+        const qsizetype bpl = image->bytesPerLine();
+        for (int y = 0; y < h; ++y) {
+            qfloat16 *dst = reinterpret_cast<qfloat16 *>(scanline);
+            for (int x = w - 1; x >= 0; --x) {
+                dst[x * 4 + 3] = qfloat16(1.0f);
+                dst[x * 4 + 2] = dst[x];
+                dst[x * 4 + 1] = dst[x];
+                dst[x * 4 + 0] = dst[x];
+            }
+            scanline += bpl;
+        }
+    } else {
+        const int h = image->height();
+        const int w = image->width();
+        uchar *scanline = image->bits();
+        const qsizetype bpl = image->bytesPerLine();
+        for (int y = 0; y < h; ++y) {
+            float *dst = reinterpret_cast<float *>(scanline);
+            for (int x = w - 1; x >= 0; --x) {
+                dst[x * 4 + 3] = 1.0f;
+                dst[x * 4 + 2] = dst[x];
+                dst[x * 4 + 1] = dst[x];
+                dst[x * 4 + 0] = dst[x];
+            }
+            scanline += bpl;
+        }
+    }
+}
+
 bool QTiffHandler::ensureHaveDirectoryCount() const
 {
     if (d->directoryCount > 0)
diff --git a/src/plugins/imageformats/tiff/qtiffhandler_p.h b/src/plugins/imageformats/tiff/qtiffhandler_p.h
index e874984..738b992 100644
--- a/src/plugins/imageformats/tiff/qtiffhandler_p.h
+++ b/src/plugins/imageformats/tiff/qtiffhandler_p.h
@@ -38,6 +38,7 @@ private:
     void convert32BitOrder(void *buffer, int width);
     void rgb48fixup(QImage *image, bool floatingPoint);
     void rgb96fixup(QImage *image);
+    void rgbFixup(QImage *image);
     const QScopedPointer<QTiffHandlerPrivate> d;
     bool ensureHaveDirectoryCount() const;
 };