| /* |
| * Copyright (C) 2006 Apple Computer, 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. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``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 COMPUTER, INC. OR |
| * 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 GIF_DECODER_H_ |
| #define GIF_DECODER_H_ |
| |
| #include "ImageDecoder.h" |
| |
| namespace WebCore { |
| |
| class GIFImageDecoderPrivate; |
| |
| // This class decodes the GIF image format. |
| class GIFImageDecoder : public ImageDecoder |
| { |
| public: |
| GIFImageDecoder(); |
| ~GIFImageDecoder(); |
| |
| // Take the data and store it. |
| virtual void setData(SharedBuffer* data, bool allDataReceived); |
| |
| // Whether or not the size information has been decoded yet. |
| virtual bool isSizeAvailable() const; |
| |
| // The total number of frames for the image. Will scan the image data for the answer |
| // (without necessarily decoding all of the individual frames). |
| virtual int frameCount(); |
| |
| // The number of repetitions to perform for an animation loop. |
| virtual int repetitionCount() const; |
| |
| virtual RGBA32Buffer* frameBufferAtIndex(size_t index); |
| |
| virtual unsigned frameDurationAtIndex(size_t index) { return 0; } |
| |
| enum GIFQuery { GIFFullQuery, GIFSizeQuery, GIFFrameCountQuery }; |
| |
| void decode(GIFQuery query, unsigned haltAtFrame) const; |
| |
| // Callbacks from the GIF reader. |
| void sizeNowAvailable(unsigned width, unsigned height); |
| void decodingHalted(unsigned bytesLeft); |
| void haveDecodedRow(unsigned frameIndex, unsigned char* rowBuffer, unsigned char* rowEnd, unsigned rowNumber, |
| unsigned repeatCount, bool writeTransparentPixels); |
| void frameComplete(unsigned frameIndex, unsigned frameDuration, RGBA32Buffer::FrameDisposalMethod disposalMethod); |
| void gifComplete(); |
| |
| private: |
| // Called to initialize the frame buffer with the given index, based on the |
| // previous frame's disposal method. |
| void initFrameBuffer(unsigned frameIndex); |
| |
| // A helper for initFrameBuffer(), this sets the size of the buffer, and |
| // fills it with transparent pixels. |
| void prepEmptyFrameBuffer(RGBA32Buffer* buffer) const; |
| |
| bool m_frameCountValid; |
| bool m_currentBufferSawAlpha; |
| mutable GIFImageDecoderPrivate* m_reader; |
| }; |
| |
| } |
| |
| #endif |