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 
12 #ifndef MEDIA_ENGINE_SIMULCAST_ENCODER_ADAPTER_H_
13 #define MEDIA_ENGINE_SIMULCAST_ENCODER_ADAPTER_H_
14 
15 #include <memory>
16 #include <stack>
17 #include <string>
18 #include <utility>
19 #include <vector>
20 
21 #include "media/engine/webrtcvideoencoderfactory.h"
22 #include "modules/video_coding/codecs/vp8/include/vp8.h"
23 #include "rtc_base/atomicops.h"
24 #include "rtc_base/sequenced_task_checker.h"
25 
26 namespace webrtc {
27 
28 class SimulcastRateAllocator;
29 class VideoEncoderFactory;
30 
31 // SimulcastEncoderAdapter implements simulcast support by creating multiple
32 // webrtc::VideoEncoder instances with the given VideoEncoderFactory.
33 // The object is created and destroyed on the worker thread, but all public
34 // interfaces should be called from the encoder task queue.
35 class SimulcastEncoderAdapter : public VP8Encoder {
36  public:
37   explicit SimulcastEncoderAdapter(VideoEncoderFactory* factory);
38   // Deprecated - use webrtc::VideoEncoderFactory instead.
39   explicit SimulcastEncoderAdapter(cricket::WebRtcVideoEncoderFactory* factory);
40   virtual ~SimulcastEncoderAdapter();
41 
42   // Implements VideoEncoder.
43   int Release() override;
44   int InitEncode(const VideoCodec* inst, int number_of_cores,
45                  size_t max_payload_size) override;
46   int Encode(const VideoFrame& input_image,
47              const CodecSpecificInfo* codec_specific_info,
48              const std::vector<FrameType>* frame_types) override;
49   int RegisterEncodeCompleteCallback(EncodedImageCallback* callback) override;
50   int SetChannelParameters(uint32_t packet_loss, int64_t rtt) override;
51   int SetRateAllocation(const BitrateAllocation& bitrate,
52                         uint32_t new_framerate) override;
53 
54   // Eventual handler for the contained encoders' EncodedImageCallbacks, but
55   // called from an internal helper that also knows the correct stream
56   // index.
57   EncodedImageCallback::Result OnEncodedImage(
58       size_t stream_idx, const EncodedImage& encoded_image,
59       const CodecSpecificInfo* codec_specific_info,
60       const RTPFragmentationHeader* fragmentation);
61 
62   VideoEncoder::ScalingSettings GetScalingSettings() const override;
63 
64   bool SupportsNativeHandle() const override;
65   const char* ImplementationName() const override;
66 
67  private:
68   struct StreamInfo {
StreamInfoStreamInfo69     StreamInfo(std::unique_ptr<VideoEncoder> encoder,
70                std::unique_ptr<EncodedImageCallback> callback, uint16_t width,
71                uint16_t height, bool send_stream)
72         : encoder(std::move(encoder)),
73           callback(std::move(callback)),
74           width(width),
75           height(height),
76           key_frame_request(false),
77           send_stream(send_stream) {}
78     std::unique_ptr<VideoEncoder> encoder;
79     std::unique_ptr<EncodedImageCallback> callback;
80     uint16_t width;
81     uint16_t height;
82     bool key_frame_request;
83     bool send_stream;
84   };
85 
86   enum class StreamResolution {
87     OTHER,
88     HIGHEST,
89     LOWEST,
90   };
91 
92   // Populate the codec settings for each simulcast stream.
93   static void PopulateStreamCodec(const webrtc::VideoCodec& inst,
94                                   int stream_index, uint32_t start_bitrate_kbps,
95                                   StreamResolution stream_resolution,
96                                   webrtc::VideoCodec* stream_codec);
97 
98   bool Initialized() const;
99 
100   void DestroyStoredEncoders();
101 
102   volatile int inited_;  // Accessed atomically.
103   VideoEncoderFactory* const factory_;
104   cricket::WebRtcVideoEncoderFactory* const cricket_factory_;
105   VideoCodec codec_;
106   std::vector<StreamInfo> streaminfos_;
107   EncodedImageCallback* encoded_complete_callback_;
108   std::string implementation_name_;
109 
110   // Used for checking the single-threaded access of the encoder interface.
111   rtc::SequencedTaskChecker encoder_queue_;
112 
113   // Store encoders in between calls to Release and InitEncode, so they don't
114   // have to be recreated. Remaining encoders are destroyed by the destructor.
115   std::stack<std::unique_ptr<VideoEncoder>> stored_encoders_;
116 };
117 
118 }  // namespace webrtc
119 
120 #endif  // MEDIA_ENGINE_SIMULCAST_ENCODER_ADAPTER_H_
121