PNG: Use frame width when applying color xform

third_party/WebKit/Source/platform/image-decoders/png/PNGImageDecoder.cpp

 /*
  * Copyright (C) 2006 Apple Computer, Inc.
  * Copyright (C) Research In Motion Limited 2009-2010. All rights reserved.
  *
  * Portions are Copyright (C) 2001 mozilla.org
  *
  * Other contributors:
  *   Stuart Parmenter <stuart@mozilla.com>
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 349 matching lines @@
 
   if (png_bytep interlaceBuffer = m_reader->interlaceBuffer()) {
     unsigned colorChannels = hasAlpha ? 4 : 3;
     row = interlaceBuffer + (rowIndex * colorChannels * size().width());
     png_progressive_combine_row(m_reader->pngPtr(), row, rowBuffer);
   }
 
   // Write the decoded row pixels to the frame buffer. The repetitive
   // form of the row write loops is for speed.
   ImageFrame::PixelData* const dstRow = buffer.getAddr(frameRect.x(), y);
-  int width = frameRect.width();
+  const int width = frameRect.width();
 
   png_bytep srcPtr = row;
   if (hasAlpha) {
     // Here we apply the color space transformation to the dst space.
     // It does not really make sense to transform to a gamma-encoded
     // space and then immediately after, perform a linear premultiply.
     // Ideally we would pass kPremul_SkAlphaType to xform->apply(),
     // instructing SkColorSpaceXform to perform the linear premultiply
     // while the pixels are a linear space.
     // We cannot do this because when we apply the gamma encoding after
     // the premultiply, we will very likely end up with valid pixels
     // where R, G, and/or B are greater than A.  The legacy drawing
     // pipeline does not know how to handle this.
     if (SkColorSpaceXform* xform = colorTransform()) {
       SkColorSpaceXform::ColorFormat colorFormat =
           SkColorSpaceXform::kRGBA_8888_ColorFormat;
-      xform->apply(colorFormat, dstRow, colorFormat, srcPtr, size().width(),
+      xform->apply(colorFormat, dstRow, colorFormat, srcPtr, width,
                    kUnpremul_SkAlphaType);
       srcPtr = png_bytep(dstRow);
     }
 
     unsigned alphaMask = 255;
     if (m_frameBufferCache[m_currentFrame].getAlphaBlendSource() ==
         ImageFrame::BlendAtopBgcolor) {
       if (buffer.premultiplyAlpha()) {
         for (auto *dstPixel = dstRow; dstPixel < dstRow + width;
              dstPixel++, srcPtr += 4) {
@@ skipping 38 matching lines @@
     for (auto *dstPixel = dstRow; dstPixel < dstRow + width;
          srcPtr += 3, ++dstPixel) {
       buffer.setRGBARaw(dstPixel, srcPtr[0], srcPtr[1], srcPtr[2], 255);
     }
 
     // We'll apply the color space xform to opaque pixels after they have been
     // written to the ImageFrame, purely because SkColorSpaceXform supports
     // RGBA (and not RGB).
     if (SkColorSpaceXform* xform = colorTransform()) {
       xform->apply(xformColorFormat(), dstRow, xformColorFormat(), dstRow,
-                   size().width(), kOpaque_SkAlphaType);
+                   width, kOpaque_SkAlphaType);
     }
   }
 
   buffer.setPixelsChanged(true);
 }
 
 void PNGImageDecoder::frameComplete() {
   if (m_currentFrame >= m_frameBufferCache.size())
     return;
 
@@ skipping 27 matching lines @@
   return m_reader->frameIsReceivedAtIndex(index);
 }
 
 float PNGImageDecoder::frameDurationAtIndex(size_t index) const {
   if (index < m_frameBufferCache.size())
     return m_frameBufferCache[index].duration();
   return 0;
 }
 
 }  // namespace blink