| // Copyright 2015 The Cobalt Authors. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #ifndef COBALT_LOADER_IMAGE_JPEG_IMAGE_DECODER_H_ |
| #define COBALT_LOADER_IMAGE_JPEG_IMAGE_DECODER_H_ |
| |
| #include <setjmp.h> |
| |
| #include <memory> |
| #include <string> |
| |
| #include "base/callback.h" |
| #include "cobalt/loader/image/image.h" |
| #include "cobalt/loader/image/image_data_decoder.h" |
| |
| // Inhibit C++ name-mangling for libjpeg functions. |
| extern "C" { |
| #include "third_party/libjpeg/jpeglib.h" |
| } |
| |
| namespace cobalt { |
| namespace loader { |
| namespace image { |
| |
| class JPEGImageDecoder : public ImageDataDecoder { |
| public: |
| // Pass true to |allow_image_decoding_to_multi_plane| to allow the decoder to |
| // produce output in YUV whenever possible, which saves both decoding time |
| // and memory footprint. Pass false to it on platforms that cannot render |
| // multi plane images efficiently, and the output will always be produced in |
| // single plane RGBA or BGRA. |
| JPEGImageDecoder(render_tree::ResourceProvider* resource_provider, |
| const base::DebuggerHooks& debugger_hooks, |
| bool allow_image_decoding_to_multi_plane); |
| ~JPEGImageDecoder() override; |
| |
| // From ImageDataDecoder |
| std::string GetTypeString() const override { return "JPEGImageDecoder"; } |
| |
| private: |
| enum OutputFormat { |
| kOutputFormatInvalid, |
| kOutputFormatYUV, |
| kOutputFormatRGBA, |
| kOutputFormatBGRA, |
| }; |
| |
| // From ImageDataDecoder |
| size_t DecodeChunkInternal(const uint8* data, size_t size) override; |
| scoped_refptr<Image> FinishInternal() override; |
| |
| bool ReadHeader(); |
| bool StartDecompress(); |
| bool DecodeProgressiveJPEG(); |
| bool ReadYUVLines(); |
| bool ReadRgbaOrGbraLines(); |
| bool ReadLines(); |
| |
| const bool allow_image_decoding_to_multi_plane_; |
| |
| jpeg_decompress_struct info_; |
| jpeg_source_mgr source_manager_; |
| jpeg_error_mgr error_manager_; |
| |
| OutputFormat output_format_ = kOutputFormatInvalid; |
| |
| // This is only used when |output_format_| is kOutputFormatRGBA or |
| // kOutputFormatBGRA. |
| std::unique_ptr<render_tree::ImageData> decoded_image_data_; |
| |
| // All the following variables are only valid when |output_format_| is |
| // kOutputFormatYUV. |
| std::unique_ptr<render_tree::RawImageMemory> raw_image_memory_; |
| |
| // Sample factors of y plane, they are 1 for yuv444 or 2 for yuv420 but may |
| // have other value combinations for other yuv formats. |
| int h_sample_factor_ = 0; |
| int v_sample_factor_ = 0; |
| // Width/height of y plane, aligned to |kDctScaleSize| * |y_sample_factor_|. |
| JDIMENSION y_plane_width_ = 0; |
| JDIMENSION y_plane_height_ = 0; |
| }; |
| |
| } // namespace image |
| } // namespace loader |
| } // namespace cobalt |
| |
| #endif // COBALT_LOADER_IMAGE_JPEG_IMAGE_DECODER_H_ |