| /* |
| * Copyright 2015 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "SkCodec.h" |
| #include "SkImageInfo.h" |
| |
| #include "gif_lib.h" |
| |
| /* |
| * |
| * This class implements the decoding for gif images |
| * |
| */ |
| class SkGifCodec : public SkCodec { |
| public: |
| |
| /* |
| * Checks the start of the stream to see if the image is a gif |
| */ |
| static bool IsGif(SkStream*); |
| |
| /* |
| * Assumes IsGif was called and returned true |
| * Creates a gif decoder |
| * Reads enough of the stream to determine the image format |
| */ |
| static SkCodec* NewFromStream(SkStream*); |
| |
| |
| protected: |
| |
| /* |
| * Initiates the gif decode |
| */ |
| Result onGetPixels(const SkImageInfo&, void*, size_t, const Options&, |
| SkPMColor*, int32_t*) override; |
| |
| SkEncodedFormat onGetEncodedFormat() const override { |
| return kGIF_SkEncodedFormat; |
| } |
| |
| private: |
| |
| /* |
| * This function cleans up the gif object after the decode completes |
| * It is used in a SkAutoTCallIProc template |
| */ |
| static int32_t CloseGif(GifFileType* gif); |
| |
| /* |
| * Frees any extension data used in the decode |
| * Used in a SkAutoTCallVProc |
| */ |
| static void FreeExtension(SavedImage* image); |
| |
| /* |
| * Creates an instance of the decoder |
| * Called only by NewFromStream |
| * |
| * @param srcInfo contains the source width and height |
| * @param stream the stream of image data |
| * @param gif pointer to library type that manages gif decode |
| * takes ownership |
| */ |
| SkGifCodec(const SkImageInfo& srcInfo, SkStream* stream, GifFileType* gif); |
| |
| SkAutoTCallIProc<GifFileType, CloseGif> fGif; // owned |
| |
| typedef SkCodec INHERITED; |
| }; |