Home | History | Annotate | Download | only in webrtc 
      1 /*
      2  *  Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
      3  *
      4  *  Use of this source code is governed by a BSD-style license
      5  *  that can be found in the LICENSE file in the root of the source
      6  *  tree. An additional intellectual property rights grant can be found
      7  *  in the file PATENTS.  All contributing project authors may
      8  *  be found in the AUTHORS file in the root of the source tree.
      9  */
     10 
     11 #ifndef WEBRTC_VIDEO_DECODER_H_
     12 #define WEBRTC_VIDEO_DECODER_H_
     13 
     14 #include <string>
     15 #include <vector>
     16 
     17 #include "webrtc/common_types.h"
     18 #include "webrtc/typedefs.h"
     19 #include "webrtc/video_frame.h"
     20 
     21 namespace webrtc {
     22 
     23 class RTPFragmentationHeader;
     24 // TODO(pbos): Expose these through a public (root) header or change these APIs.
     25 struct CodecSpecificInfo;
     26 struct VideoCodec;
     27 
     28 class DecodedImageCallback {
     29  public:
     30   virtual ~DecodedImageCallback() {}
     31 
     32   virtual int32_t Decoded(VideoFrame& decodedImage) = 0;
     33   // Provides an alternative interface that allows the decoder to specify the
     34   // decode time excluding waiting time for any previous pending frame to
     35   // return. This is necessary for breaking positive feedback in the delay
     36   // estimation when the decoder has a single output buffer.
     37   // TODO(perkj): Remove default implementation when chromium has been updated.
     38   virtual int32_t Decoded(VideoFrame& decodedImage, int64_t decode_time_ms) {
     39     // The default implementation ignores custom decode time value.
     40     return Decoded(decodedImage);
     41   }
     42 
     43   virtual int32_t ReceivedDecodedReferenceFrame(const uint64_t pictureId) {
     44     return -1;
     45   }
     46 
     47   virtual int32_t ReceivedDecodedFrame(const uint64_t pictureId) { return -1; }
     48 };
     49 
     50 class VideoDecoder {
     51  public:
     52   enum DecoderType {
     53     kH264,
     54     kVp8,
     55     kVp9,
     56     kUnsupportedCodec,
     57   };
     58 
     59   static VideoDecoder* Create(DecoderType codec_type);
     60 
     61   virtual ~VideoDecoder() {}
     62 
     63   virtual int32_t InitDecode(const VideoCodec* codec_settings,
     64                              int32_t number_of_cores) = 0;
     65 
     66   virtual int32_t Decode(const EncodedImage& input_image,
     67                          bool missing_frames,
     68                          const RTPFragmentationHeader* fragmentation,
     69                          const CodecSpecificInfo* codec_specific_info = NULL,
     70                          int64_t render_time_ms = -1) = 0;
     71 
     72   virtual int32_t RegisterDecodeCompleteCallback(
     73       DecodedImageCallback* callback) = 0;
     74 
     75   virtual int32_t Release() = 0;
     76   virtual int32_t Reset() = 0;
     77 
     78   // Returns true if the decoder prefer to decode frames late.
     79   // That is, it can not decode infinite number of frames before the decoded
     80   // frame is consumed.
     81   virtual bool PrefersLateDecoding() const { return true; }
     82 
     83   virtual const char* ImplementationName() const { return "unknown"; }
     84 };
     85 
     86 // Class used to wrap external VideoDecoders to provide a fallback option on
     87 // software decoding when a hardware decoder fails to decode a stream due to
     88 // hardware restrictions, such as max resolution.
     89 class VideoDecoderSoftwareFallbackWrapper : public webrtc::VideoDecoder {
     90  public:
     91   VideoDecoderSoftwareFallbackWrapper(VideoCodecType codec_type,
     92                                       VideoDecoder* decoder);
     93 
     94   int32_t InitDecode(const VideoCodec* codec_settings,
     95                      int32_t number_of_cores) override;
     96 
     97   int32_t Decode(const EncodedImage& input_image,
     98                  bool missing_frames,
     99                  const RTPFragmentationHeader* fragmentation,
    100                  const CodecSpecificInfo* codec_specific_info,
    101                  int64_t render_time_ms) override;
    102 
    103   int32_t RegisterDecodeCompleteCallback(
    104       DecodedImageCallback* callback) override;
    105 
    106   int32_t Release() override;
    107   int32_t Reset() override;
    108   bool PrefersLateDecoding() const override;
    109 
    110   const char* ImplementationName() const override;
    111 
    112  private:
    113   bool InitFallbackDecoder();
    114 
    115   const DecoderType decoder_type_;
    116   VideoDecoder* const decoder_;
    117 
    118   VideoCodec codec_settings_;
    119   int32_t number_of_cores_;
    120   std::string fallback_implementation_name_;
    121   rtc::scoped_ptr<VideoDecoder> fallback_decoder_;
    122   DecodedImageCallback* callback_;
    123 };
    124 
    125 }  // namespace webrtc
    126 
    127 #endif  // WEBRTC_VIDEO_DECODER_H_
    128