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simulcast_encoder_adapter.h (8138B)


      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 <atomic>
     16 #include <cstddef>
     17 #include <cstdint>
     18 #include <list>
     19 #include <memory>
     20 #include <optional>
     21 #include <vector>
     22 
     23 #include "absl/base/nullability.h"
     24 #include "api/environment/environment.h"
     25 #include "api/fec_controller_override.h"
     26 #include "api/sequence_checker.h"
     27 #include "api/units/timestamp.h"
     28 #include "api/video/encoded_image.h"
     29 #include "api/video/video_frame.h"
     30 #include "api/video/video_frame_type.h"
     31 #include "api/video_codecs/sdp_video_format.h"
     32 #include "api/video_codecs/video_codec.h"
     33 #include "api/video_codecs/video_encoder.h"
     34 #include "api/video_codecs/video_encoder_factory.h"
     35 #include "common_video/framerate_controller.h"
     36 #include "modules/video_coding/include/video_codec_interface.h"
     37 #include "rtc_base/experiments/encoder_info_settings.h"
     38 #include "rtc_base/system/no_unique_address.h"
     39 #include "rtc_base/system/rtc_export.h"
     40 
     41 namespace webrtc {
     42 
     43 // SimulcastEncoderAdapter implements simulcast support by creating multiple
     44 // VideoEncoder instances with the given VideoEncoderFactory.
     45 // The object is created and destroyed on the worker thread, but all public
     46 // interfaces should be called from the encoder task queue.
     47 class RTC_EXPORT SimulcastEncoderAdapter : public VideoEncoder {
     48 public:
     49  // `primary_factory` produces the first-choice encoders to use.
     50  // `fallback_factory`, if non-null, is used to create fallback encoder that
     51  // will be used if InitEncode() fails for the primary encoder.
     52  SimulcastEncoderAdapter(const Environment& env,
     53                          VideoEncoderFactory* absl_nonnull primary_factory,
     54                          VideoEncoderFactory* absl_nullable fallback_factory,
     55                          const SdpVideoFormat& format);
     56 
     57  ~SimulcastEncoderAdapter() override;
     58 
     59  // Implements VideoEncoder.
     60  void SetFecControllerOverride(
     61      FecControllerOverride* fec_controller_override) override;
     62  int Release() override;
     63  int InitEncode(const VideoCodec* codec_settings,
     64                 const VideoEncoder::Settings& settings) override;
     65  int Encode(const VideoFrame& input_image,
     66             const std::vector<VideoFrameType>* frame_types) override;
     67  int RegisterEncodeCompleteCallback(EncodedImageCallback* callback) override;
     68  void SetRates(const RateControlParameters& parameters) override;
     69  void OnPacketLossRateUpdate(float packet_loss_rate) override;
     70  void OnRttUpdate(int64_t rtt_ms) override;
     71  void OnLossNotification(const LossNotification& loss_notification) override;
     72 
     73  EncoderInfo GetEncoderInfo() const override;
     74 
     75 protected:
     76  void DestroyStoredEncoders();
     77 
     78 private:
     79  class EncoderContext {
     80   public:
     81    EncoderContext(std::unique_ptr<VideoEncoder> encoder,
     82                   bool prefer_temporal_support,
     83                   VideoEncoder::EncoderInfo primary_info,
     84                   VideoEncoder::EncoderInfo fallback_info,
     85                   SdpVideoFormat video_format);
     86    EncoderContext& operator=(EncoderContext&&) = delete;
     87 
     88    VideoEncoder& encoder() { return *encoder_; }
     89    bool prefer_temporal_support() { return prefer_temporal_support_; }
     90    void Release();
     91 
     92    const VideoEncoder::EncoderInfo& PrimaryInfo() { return primary_info_; }
     93 
     94    const VideoEncoder::EncoderInfo& FallbackInfo() { return fallback_info_; }
     95 
     96    const SdpVideoFormat& video_format() { return video_format_; }
     97 
     98   private:
     99    std::unique_ptr<VideoEncoder> encoder_;
    100    bool prefer_temporal_support_;
    101    const VideoEncoder::EncoderInfo primary_info_;
    102    const VideoEncoder::EncoderInfo fallback_info_;
    103    const SdpVideoFormat video_format_;
    104  };
    105 
    106  class StreamContext : public EncodedImageCallback {
    107   public:
    108    StreamContext(SimulcastEncoderAdapter* parent,
    109                  std::unique_ptr<EncoderContext> encoder_context,
    110                  std::unique_ptr<FramerateController> framerate_controller,
    111                  int stream_idx,
    112                  uint16_t width,
    113                  uint16_t height,
    114                  bool send_stream);
    115    StreamContext(StreamContext&& rhs);
    116    StreamContext& operator=(StreamContext&&) = delete;
    117    ~StreamContext() override;
    118 
    119    Result OnEncodedImage(
    120        const EncodedImage& encoded_image,
    121        const CodecSpecificInfo* codec_specific_info) override;
    122    void OnDroppedFrame(DropReason reason) override;
    123 
    124    VideoEncoder& encoder() { return encoder_context_->encoder(); }
    125    const VideoEncoder& encoder() const { return encoder_context_->encoder(); }
    126    int stream_idx() const { return stream_idx_; }
    127    uint16_t width() const { return width_; }
    128    uint16_t height() const { return height_; }
    129    bool is_keyframe_needed() const {
    130      return !is_paused_ && is_keyframe_needed_;
    131    }
    132    void set_is_keyframe_needed() { is_keyframe_needed_ = true; }
    133    bool is_paused() const { return is_paused_; }
    134    void set_is_paused(bool is_paused) { is_paused_ = is_paused; }
    135    std::optional<double> target_fps() const {
    136      return framerate_controller_ == nullptr
    137                 ? std::nullopt
    138                 : std::optional<double>(
    139                       framerate_controller_->GetMaxFramerate());
    140    }
    141 
    142    std::unique_ptr<EncoderContext> ReleaseEncoderContext() &&;
    143    void OnKeyframe(Timestamp timestamp);
    144    bool ShouldDropFrame(Timestamp timestamp);
    145 
    146   private:
    147    SimulcastEncoderAdapter* const parent_;
    148    std::unique_ptr<EncoderContext> encoder_context_;
    149    std::unique_ptr<FramerateController> framerate_controller_;
    150    const int stream_idx_;
    151    const uint16_t width_;
    152    const uint16_t height_;
    153    bool is_keyframe_needed_;
    154    bool is_paused_;
    155  };
    156 
    157  bool Initialized() const;
    158 
    159  // This method creates encoder. May reuse previously created encoders from
    160  // `cached_encoder_contexts_`. It's const because it's used from
    161  // const GetEncoderInfo().
    162  std::unique_ptr<EncoderContext> FetchOrCreateEncoderContext(
    163      bool is_lowest_quality_stream,
    164      std::optional<int> stream_idx) const;
    165 
    166  VideoCodec MakeStreamCodec(const VideoCodec& codec,
    167                             int stream_idx,
    168                             uint32_t start_bitrate_kbps,
    169                             bool is_lowest_quality_stream,
    170                             bool is_highest_quality_stream);
    171 
    172  EncodedImageCallback::Result OnEncodedImage(
    173      size_t stream_idx,
    174      const EncodedImage& encoded_image,
    175      const CodecSpecificInfo* codec_specific_info);
    176 
    177  void OnDroppedFrame(size_t stream_idx);
    178 
    179  void OverrideFromFieldTrial(VideoEncoder::EncoderInfo* info) const;
    180 
    181  const Environment env_;
    182  std::atomic<int> inited_;
    183  VideoEncoderFactory* const primary_encoder_factory_;
    184  VideoEncoderFactory* const fallback_encoder_factory_;
    185  const SdpVideoFormat video_format_;
    186  VideoCodec codec_;
    187  int total_streams_count_;
    188  bool bypass_mode_;
    189  std::vector<StreamContext> stream_contexts_;
    190  EncodedImageCallback* encoded_complete_callback_;
    191 
    192  // Used for checking the single-threaded access of the encoder interface.
    193  RTC_NO_UNIQUE_ADDRESS SequenceChecker encoder_queue_;
    194 
    195  // Store previously created and released encoders , so they don't have to be
    196  // recreated. Remaining encoders are destroyed by the destructor.
    197  // Marked as `mutable` becuase we may need to temporarily create encoder in
    198  // GetEncoderInfo(), which is const.
    199  mutable std::list<std::unique_ptr<EncoderContext>> cached_encoder_contexts_;
    200 
    201  const bool boost_base_layer_quality_;
    202  const bool prefer_temporal_support_on_base_layer_;
    203  const bool per_layer_pli_;
    204  const bool drop_unaligned_resolution_;
    205 
    206  const SimulcastEncoderAdapterEncoderInfoSettings encoder_info_override_;
    207 };
    208 
    209 }  // namespace webrtc
    210 
    211 #endif  // MEDIA_ENGINE_SIMULCAST_ENCODER_ADAPTER_H_