Index: third_party/WebKit/Source/platform/image-decoders/gif/GIFImageDecoder.cpp |
diff --git a/third_party/WebKit/Source/platform/image-decoders/gif/GIFImageDecoder.cpp b/third_party/WebKit/Source/platform/image-decoders/gif/GIFImageDecoder.cpp |
index a769b6d09bb28180c851a3f3e7128ba6077dbcf1..ba4cca2bb13c8da2bcc7cbc66cdad6fd869999b3 100644 |
--- a/third_party/WebKit/Source/platform/image-decoders/gif/GIFImageDecoder.cpp |
+++ b/third_party/WebKit/Source/platform/image-decoders/gif/GIFImageDecoder.cpp |
@@ -356,11 +356,14 @@ bool GIFImageDecoder::initFrameBuffer(size_t frameIndex) |
if (!buffer->setSizeAndColorProfile(size().width(), size().height(), ImageFrame::ICCProfile())) |
return setFailed(); |
} else { |
- const ImageFrame* prevBuffer = &m_frameBufferCache[requiredPreviousFrameIndex]; |
+ ImageFrame* prevBuffer = &m_frameBufferCache[requiredPreviousFrameIndex]; |
ASSERT(prevBuffer->getStatus() == ImageFrame::FrameComplete); |
- // Preserve the last frame as the starting state for this frame. |
- if (!buffer->copyBitmapData(*prevBuffer)) |
+ // We try to reuse |prevBuffer| as starting state to avoid copying. |
+ // For DisposeOverwritePrevious, the next frame will also use |
+ // |prevBuffer| as its starting state, so we can't take over its image |
+ // data using takeBitmapDataIfWritable. Copy the data instead. |
+ if ((buffer->getDisposalMethod() == ImageFrame::DisposeOverwritePrevious || !buffer->takeBitmapDataIfWritable(prevBuffer)) && !buffer->copyBitmapData(*prevBuffer)) |
return setFailed(); |
if (prevBuffer->getDisposalMethod() == ImageFrame::DisposeOverwriteBgcolor) { |