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/*
* Copyright (C) 2010 Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
* its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef WEBPImageDecoder_h
#define WEBPImageDecoder_h
#include "platform/image-decoders/ImageDecoder.h"
#include "third_party/skia/include/core/SkData.h"
#include "webp/decode.h"
#include "webp/demux.h"
#include "wtf/RefPtr.h"
namespace blink {
class PLATFORM_EXPORT WEBPImageDecoder final : public ImageDecoder {
WTF_MAKE_NONCOPYABLE(WEBPImageDecoder);
public:
WEBPImageDecoder(AlphaOption, const ColorBehavior&, size_t maxDecodedBytes);
~WEBPImageDecoder() override;
// ImageDecoder:
String filenameExtension() const override { return "webp"; }
void onSetData(SegmentReader* data) override;
int repetitionCount() const override;
bool frameIsCompleteAtIndex(size_t) const override;
float frameDurationAtIndex(size_t) const override;
private:
// ImageDecoder:
virtual void decodeSize() { updateDemuxer(); }
size_t decodeFrameCount() override;
void initializeNewFrame(size_t) override;
void decode(size_t) override;
bool decodeSingleFrame(const uint8_t* dataBytes,
size_t dataSize,
size_t frameIndex);
// For WebP images, the frame status needs to be FrameComplete to decode
// subsequent frames that depend on frame |index|. The reason for this is that
// WebP uses the previous frame for alpha blending, in applyPostProcessing().
//
// Before calling this, verify that frame |index| exists by checking that
// |index| is smaller than |m_frameBufferCache|.size().
bool frameStatusSufficientForSuccessors(size_t index) override {
DCHECK(index < m_frameBufferCache.size());
return m_frameBufferCache[index].getStatus() == ImageFrame::FrameComplete;
}
WebPIDecoder* m_decoder;
WebPDecBuffer m_decoderBuffer;
int m_formatFlags;
bool m_frameBackgroundHasAlpha;
void readColorProfile();
bool updateDemuxer();
// Set |m_frameBackgroundHasAlpha| based on this frame's characteristics.
// Before calling this method, the caller must verify that the frame exists.
void onInitFrameBuffer(size_t frameIndex) override;
// When the blending method of this frame is BlendAtopPreviousFrame, the
// previous frame's buffer is necessary to decode this frame in
// applyPostProcessing, so we can't take over the data. Before calling this
// method, the caller must verify that the frame exists.
bool canReusePreviousFrameBuffer(size_t frameIndex) const override;
void applyPostProcessing(size_t frameIndex);
void clearFrameBuffer(size_t frameIndex) override;
WebPDemuxer* m_demux;
WebPDemuxState m_demuxState;
bool m_haveAlreadyParsedThisData;
int m_repetitionCount;
int m_decodedHeight;
typedef void (*AlphaBlendFunction)(ImageFrame&, ImageFrame&, int, int, int);
AlphaBlendFunction m_blendFunction;
void clear();
void clearDecoder();
// FIXME: Update libwebp's API so it does not require copying the data on each
// update.
sk_sp<SkData> m_consolidatedData;
};
} // namespace blink
#endif
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