1 // Copyright 2015 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef MEDIA_GPU_VP8_DECODER_H_ 6 #define MEDIA_GPU_VP8_DECODER_H_ 7 8 #include <stddef.h> 9 #include <stdint.h> 10 11 #include <memory> 12 13 #include "base/macros.h" 14 #include "base/memory/ref_counted.h" 15 #include "media/gpu/accelerated_video_decoder.h" 16 #include "media/gpu/vp8_picture.h" 17 #include "media/gpu/vp8_reference_frame_vector.h" 18 #include "media/parsers/vp8_parser.h" 19 20 namespace media { 21 22 // Clients of this class are expected to pass raw VP8 stream and are expected 23 // to provide an implementation of VP8Accelerator for offloading final steps 24 // of the decoding process. 25 // 26 // This class must be created, called and destroyed on a single thread, and 27 // does nothing internally on any other thread. 28 class MEDIA_GPU_EXPORT VP8Decoder : public AcceleratedVideoDecoder { 29 public: 30 class MEDIA_GPU_EXPORT VP8Accelerator { 31 public: 32 VP8Accelerator(); 33 virtual ~VP8Accelerator(); 34 35 // Create a new VP8Picture that the decoder client can use for decoding 36 // and pass back to this accelerator for decoding or reference. 37 // When the picture is no longer needed by decoder, it will just drop 38 // its reference to it, and it may do so at any time. 39 // Note that this may return nullptr if accelerator is not able to provide 40 // any new pictures at given time. The decoder is expected to handle 41 // this situation as normal and return from Decode() with kRanOutOfSurfaces. 42 virtual scoped_refptr<VP8Picture> CreateVP8Picture() = 0; 43 44 // Submits decode for |pic|, using |reference_frames| as references, as per 45 // VP8 specification. Returns true if successful. 46 virtual bool SubmitDecode( 47 scoped_refptr<VP8Picture> pic, 48 const Vp8ReferenceFrameVector& reference_frames) = 0; 49 50 // Schedule output (display) of |pic|. Note that returning from this 51 // method does not mean that |pic| has already been outputted (displayed), 52 // but guarantees that all pictures will be outputted in the same order 53 // as this method was called for them. Decoder may drop its reference 54 // to |pic| after calling this method. 55 // Return true if successful. 56 virtual bool OutputPicture(scoped_refptr<VP8Picture> pic) = 0; 57 58 private: 59 DISALLOW_COPY_AND_ASSIGN(VP8Accelerator); 60 }; 61 62 explicit VP8Decoder(std::unique_ptr<VP8Accelerator> accelerator); 63 ~VP8Decoder() override; 64 65 // AcceleratedVideoDecoder implementation. 66 void SetStream(int32_t id, const DecoderBuffer& decoder_buffer) override; 67 bool Flush() override WARN_UNUSED_RESULT; 68 void Reset() override; 69 DecodeResult Decode() override WARN_UNUSED_RESULT; 70 gfx::Size GetPicSize() const override; 71 gfx::Rect GetVisibleRect() const override; 72 VideoCodecProfile GetProfile() const override; 73 size_t GetRequiredNumOfPictures() const override; 74 size_t GetNumReferenceFrames() const override; 75 76 private: 77 bool DecodeAndOutputCurrentFrame(scoped_refptr<VP8Picture> pic); 78 79 enum State { 80 kNeedStreamMetadata, // After initialization, need a keyframe. 81 kDecoding, // Ready to decode from any point. 82 kAfterReset, // After Reset(), need a resume point. 83 kError, // Error in decode, can't continue. 84 }; 85 86 State state_; 87 88 Vp8Parser parser_; 89 90 std::unique_ptr<Vp8FrameHeader> curr_frame_hdr_; 91 Vp8ReferenceFrameVector ref_frames_; 92 93 // Current stream buffer id; to be assigned to pictures decoded from it. 94 static constexpr int32_t kInvalidId = -1; 95 int32_t stream_id_ = kInvalidId; 96 int32_t last_decoded_stream_id_ = kInvalidId; 97 size_t size_change_failure_counter_ = 0; 98 99 const uint8_t* curr_frame_start_; 100 size_t frame_size_; 101 102 gfx::Size pic_size_; 103 int horizontal_scale_; 104 int vertical_scale_; 105 106 const std::unique_ptr<VP8Accelerator> accelerator_; 107 108 DISALLOW_COPY_AND_ASSIGN(VP8Decoder); 109 }; 110 111 } // namespace media 112 113 #endif // MEDIA_GPU_VP8_DECODER_H_ 114