| /* |
| * Copyright (c) 2012 The WebRTC project authors. All Rights Reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| #ifndef VIDEO_VIDEO_STREAM_ENCODER_H_ |
| #define VIDEO_VIDEO_STREAM_ENCODER_H_ |
| |
| #include <atomic> |
| #include <map> |
| #include <memory> |
| #include <string> |
| #include <vector> |
| |
| #include "api/units/data_rate.h" |
| #include "api/video/video_bitrate_allocator.h" |
| #include "api/video/video_rotation.h" |
| #include "api/video/video_sink_interface.h" |
| #include "api/video/video_stream_encoder_interface.h" |
| #include "api/video/video_stream_encoder_observer.h" |
| #include "api/video/video_stream_encoder_settings.h" |
| #include "api/video_codecs/video_codec.h" |
| #include "api/video_codecs/video_encoder.h" |
| #include "modules/video_coding/utility/frame_dropper.h" |
| #include "modules/video_coding/utility/quality_scaler.h" |
| #include "rtc_base/critical_section.h" |
| #include "rtc_base/event.h" |
| #include "rtc_base/experiments/balanced_degradation_settings.h" |
| #include "rtc_base/experiments/quality_scaler_settings.h" |
| #include "rtc_base/experiments/rate_control_settings.h" |
| #include "rtc_base/numerics/exp_filter.h" |
| #include "rtc_base/race_checker.h" |
| #include "rtc_base/rate_statistics.h" |
| #include "rtc_base/synchronization/sequence_checker.h" |
| #include "rtc_base/task_queue.h" |
| #include "system_wrappers/include/clock.h" |
| #include "video/encoder_bitrate_adjuster.h" |
| #include "video/frame_encode_metadata_writer.h" |
| #include "video/overuse_frame_detector.h" |
| |
| namespace webrtc { |
| |
| // VideoStreamEncoder represent a video encoder that accepts raw video frames as |
| // input and produces an encoded bit stream. |
| // Usage: |
| // Instantiate. |
| // Call SetSink. |
| // Call SetSource. |
| // Call ConfigureEncoder with the codec settings. |
| // Call Stop() when done. |
| class VideoStreamEncoder : public VideoStreamEncoderInterface, |
| private EncodedImageCallback, |
| // Protected only to provide access to tests. |
| protected AdaptationObserverInterface { |
| public: |
| VideoStreamEncoder(Clock* clock, |
| uint32_t number_of_cores, |
| VideoStreamEncoderObserver* encoder_stats_observer, |
| const VideoStreamEncoderSettings& settings, |
| std::unique_ptr<OveruseFrameDetector> overuse_detector, |
| TaskQueueFactory* task_queue_factory); |
| ~VideoStreamEncoder() override; |
| |
| void SetSource(rtc::VideoSourceInterface<VideoFrame>* source, |
| const DegradationPreference& degradation_preference) override; |
| |
| void SetSink(EncoderSink* sink, bool rotation_applied) override; |
| |
| // TODO(perkj): Can we remove VideoCodec.startBitrate ? |
| void SetStartBitrate(int start_bitrate_bps) override; |
| |
| void SetBitrateAllocationObserver( |
| VideoBitrateAllocationObserver* bitrate_observer) override; |
| |
| void SetFecControllerOverride( |
| FecControllerOverride* fec_controller_override) override; |
| |
| void ConfigureEncoder(VideoEncoderConfig config, |
| size_t max_data_payload_length) override; |
| |
| // Permanently stop encoding. After this method has returned, it is |
| // guaranteed that no encoded frames will be delivered to the sink. |
| void Stop() override; |
| |
| void SendKeyFrame() override; |
| |
| void OnLossNotification( |
| const VideoEncoder::LossNotification& loss_notification) override; |
| |
| void OnBitrateUpdated(DataRate target_bitrate, |
| DataRate stable_target_bitrate, |
| DataRate target_headroom, |
| uint8_t fraction_lost, |
| int64_t round_trip_time_ms) override; |
| |
| protected: |
| // Used for testing. For example the |ScalingObserverInterface| methods must |
| // be called on |encoder_queue_|. |
| rtc::TaskQueue* encoder_queue() { return &encoder_queue_; } |
| |
| // AdaptationObserverInterface implementation. |
| // These methods are protected for easier testing. |
| void AdaptUp(AdaptReason reason) override; |
| bool AdaptDown(AdaptReason reason) override; |
| |
| private: |
| class VideoSourceProxy; |
| |
| class VideoFrameInfo { |
| public: |
| VideoFrameInfo(int width, int height, bool is_texture) |
| : width(width), height(height), is_texture(is_texture) {} |
| int width; |
| int height; |
| bool is_texture; |
| int pixel_count() const { return width * height; } |
| }; |
| |
| struct EncoderRateSettings { |
| EncoderRateSettings(); |
| EncoderRateSettings(const VideoBitrateAllocation& bitrate, |
| double framerate_fps, |
| DataRate bandwidth_allocation, |
| DataRate encoder_target, |
| DataRate stable_encoder_target); |
| bool operator==(const EncoderRateSettings& rhs) const; |
| bool operator!=(const EncoderRateSettings& rhs) const; |
| |
| VideoEncoder::RateControlParameters rate_control; |
| // This is the scalar target bitrate before the VideoBitrateAllocator, i.e. |
| // the |target_bitrate| argument of the OnBitrateUpdated() method. This is |
| // needed because the bitrate allocator may truncate the total bitrate and a |
| // later call to the same allocator instance, e.g. |
| // |using last_encoder_rate_setings_->bitrate.get_sum_bps()|, may trick it |
| // into thinking the available bitrate has decreased since the last call. |
| DataRate encoder_target; |
| DataRate stable_encoder_target; |
| }; |
| |
| void ReconfigureEncoder() RTC_RUN_ON(&encoder_queue_); |
| |
| void ConfigureQualityScaler(const VideoEncoder::EncoderInfo& encoder_info); |
| |
| // Implements VideoSinkInterface. |
| void OnFrame(const VideoFrame& video_frame) override; |
| void OnDiscardedFrame() override; |
| |
| void MaybeEncodeVideoFrame(const VideoFrame& frame, |
| int64_t time_when_posted_in_ms); |
| |
| void EncodeVideoFrame(const VideoFrame& frame, |
| int64_t time_when_posted_in_ms); |
| // Indicates wether frame should be dropped because the pixel count is too |
| // large for the current bitrate configuration. |
| bool DropDueToSize(uint32_t pixel_count) const RTC_RUN_ON(&encoder_queue_); |
| |
| // Implements EncodedImageCallback. |
| EncodedImageCallback::Result OnEncodedImage( |
| const EncodedImage& encoded_image, |
| const CodecSpecificInfo* codec_specific_info, |
| const RTPFragmentationHeader* fragmentation) override; |
| |
| void OnDroppedFrame(EncodedImageCallback::DropReason reason) override; |
| |
| bool EncoderPaused() const; |
| void TraceFrameDropStart(); |
| void TraceFrameDropEnd(); |
| |
| // Returns a copy of |rate_settings| with the |bitrate| field updated using |
| // the current VideoBitrateAllocator, and notifies any listeners of the new |
| // allocation. |
| EncoderRateSettings UpdateBitrateAllocationAndNotifyObserver( |
| const EncoderRateSettings& rate_settings) RTC_RUN_ON(&encoder_queue_); |
| |
| uint32_t GetInputFramerateFps() RTC_RUN_ON(&encoder_queue_); |
| void SetEncoderRates(const EncoderRateSettings& rate_settings) |
| RTC_RUN_ON(&encoder_queue_); |
| |
| // Class holding adaptation information. |
| class AdaptCounter final { |
| public: |
| AdaptCounter(); |
| ~AdaptCounter(); |
| |
| // Get number of adaptation downscales for |reason|. |
| VideoStreamEncoderObserver::AdaptationSteps Counts(int reason) const; |
| |
| std::string ToString() const; |
| |
| void IncrementFramerate(int reason); |
| void IncrementResolution(int reason); |
| void DecrementFramerate(int reason); |
| void DecrementResolution(int reason); |
| void DecrementFramerate(int reason, int cur_fps); |
| |
| // Gets the total number of downgrades (for all adapt reasons). |
| int FramerateCount() const; |
| int ResolutionCount() const; |
| |
| // Gets the total number of downgrades for |reason|. |
| int FramerateCount(int reason) const; |
| int ResolutionCount(int reason) const; |
| int TotalCount(int reason) const; |
| |
| private: |
| std::string ToString(const std::vector<int>& counters) const; |
| int Count(const std::vector<int>& counters) const; |
| void MoveCount(std::vector<int>* counters, int from_reason); |
| |
| // Degradation counters holding number of framerate/resolution reductions |
| // per adapt reason. |
| std::vector<int> fps_counters_; |
| std::vector<int> resolution_counters_; |
| }; |
| |
| AdaptCounter& GetAdaptCounter() RTC_RUN_ON(&encoder_queue_); |
| const AdaptCounter& GetConstAdaptCounter() RTC_RUN_ON(&encoder_queue_); |
| void UpdateAdaptationStats(AdaptReason reason) RTC_RUN_ON(&encoder_queue_); |
| VideoStreamEncoderObserver::AdaptationSteps GetActiveCounts( |
| AdaptReason reason) RTC_RUN_ON(&encoder_queue_); |
| bool CanAdaptUpResolution(int pixels, uint32_t bitrate_bps) const |
| RTC_RUN_ON(&encoder_queue_); |
| void RunPostEncode(EncodedImage encoded_image, |
| int64_t time_sent_us, |
| int temporal_index); |
| bool HasInternalSource() const RTC_RUN_ON(&encoder_queue_); |
| void ReleaseEncoder() RTC_RUN_ON(&encoder_queue_); |
| |
| rtc::Event shutdown_event_; |
| |
| const uint32_t number_of_cores_; |
| // Counts how many frames we've dropped in the initial framedrop phase. |
| int initial_framedrop_; |
| const bool initial_framedrop_on_bwe_enabled_; |
| bool has_seen_first_significant_bwe_change_ = false; |
| |
| const bool quality_scaling_experiment_enabled_; |
| |
| const std::unique_ptr<VideoSourceProxy> source_proxy_; |
| EncoderSink* sink_; |
| const VideoStreamEncoderSettings settings_; |
| const RateControlSettings rate_control_settings_; |
| const QualityScalerSettings quality_scaler_settings_; |
| |
| const std::unique_ptr<OveruseFrameDetector> overuse_detector_ |
| RTC_PT_GUARDED_BY(&encoder_queue_); |
| std::unique_ptr<QualityScaler> quality_scaler_ RTC_GUARDED_BY(&encoder_queue_) |
| RTC_PT_GUARDED_BY(&encoder_queue_); |
| |
| VideoStreamEncoderObserver* const encoder_stats_observer_; |
| // |thread_checker_| checks that public methods that are related to lifetime |
| // of VideoStreamEncoder are called on the same thread. |
| rtc::ThreadChecker thread_checker_; |
| |
| VideoEncoderConfig encoder_config_ RTC_GUARDED_BY(&encoder_queue_); |
| std::unique_ptr<VideoEncoder> encoder_ RTC_GUARDED_BY(&encoder_queue_) |
| RTC_PT_GUARDED_BY(&encoder_queue_); |
| bool encoder_initialized_; |
| std::unique_ptr<VideoBitrateAllocator> rate_allocator_ |
| RTC_GUARDED_BY(&encoder_queue_) RTC_PT_GUARDED_BY(&encoder_queue_); |
| // The maximum frame rate of the current codec configuration, as determined |
| // at the last ReconfigureEncoder() call. |
| int max_framerate_ RTC_GUARDED_BY(&encoder_queue_); |
| |
| // Set when ConfigureEncoder has been called in order to lazy reconfigure the |
| // encoder on the next frame. |
| bool pending_encoder_reconfiguration_ RTC_GUARDED_BY(&encoder_queue_); |
| // Set when configuration must create a new encoder object, e.g., |
| // because of a codec change. |
| bool pending_encoder_creation_ RTC_GUARDED_BY(&encoder_queue_); |
| |
| absl::optional<VideoFrameInfo> last_frame_info_ |
| RTC_GUARDED_BY(&encoder_queue_); |
| int crop_width_ RTC_GUARDED_BY(&encoder_queue_); |
| int crop_height_ RTC_GUARDED_BY(&encoder_queue_); |
| uint32_t encoder_start_bitrate_bps_ RTC_GUARDED_BY(&encoder_queue_); |
| int set_start_bitrate_bps_ RTC_GUARDED_BY(&encoder_queue_); |
| int64_t set_start_bitrate_time_ms_ RTC_GUARDED_BY(&encoder_queue_); |
| bool has_seen_first_bwe_drop_ RTC_GUARDED_BY(&encoder_queue_); |
| size_t max_data_payload_length_ RTC_GUARDED_BY(&encoder_queue_); |
| absl::optional<EncoderRateSettings> last_encoder_rate_settings_ |
| RTC_GUARDED_BY(&encoder_queue_); |
| bool encoder_paused_and_dropped_frame_ RTC_GUARDED_BY(&encoder_queue_); |
| |
| // Set to true if at least one frame was sent to encoder since last encoder |
| // initialization. |
| bool was_encode_called_since_last_initialization_ |
| RTC_GUARDED_BY(&encoder_queue_); |
| |
| bool encoder_failed_ RTC_GUARDED_BY(&encoder_queue_); |
| Clock* const clock_; |
| // Counters used for deciding if the video resolution or framerate is |
| // currently restricted, and if so, why, on a per degradation preference |
| // basis. |
| // TODO(sprang): Replace this with a state holding a relative overuse measure |
| // instead, that can be translated into suitable down-scale or fps limit. |
| std::map<const DegradationPreference, AdaptCounter> adapt_counters_ |
| RTC_GUARDED_BY(&encoder_queue_); |
| // Set depending on degradation preferences. |
| DegradationPreference degradation_preference_ RTC_GUARDED_BY(&encoder_queue_); |
| |
| const BalancedDegradationSettings balanced_settings_; |
| |
| struct AdaptationRequest { |
| // The pixel count produced by the source at the time of the adaptation. |
| int input_pixel_count_; |
| // Framerate received from the source at the time of the adaptation. |
| int framerate_fps_; |
| // Indicates if request was to adapt up or down. |
| enum class Mode { kAdaptUp, kAdaptDown } mode_; |
| }; |
| // Stores a snapshot of the last adaptation request triggered by an AdaptUp |
| // or AdaptDown signal. |
| absl::optional<AdaptationRequest> last_adaptation_request_ |
| RTC_GUARDED_BY(&encoder_queue_); |
| |
| rtc::RaceChecker incoming_frame_race_checker_ |
| RTC_GUARDED_BY(incoming_frame_race_checker_); |
| std::atomic<int> posted_frames_waiting_for_encode_; |
| // Used to make sure incoming time stamp is increasing for every frame. |
| int64_t last_captured_timestamp_ RTC_GUARDED_BY(incoming_frame_race_checker_); |
| // Delta used for translating between NTP and internal timestamps. |
| const int64_t delta_ntp_internal_ms_ |
| RTC_GUARDED_BY(incoming_frame_race_checker_); |
| |
| int64_t last_frame_log_ms_ RTC_GUARDED_BY(incoming_frame_race_checker_); |
| int captured_frame_count_ RTC_GUARDED_BY(&encoder_queue_); |
| int dropped_frame_count_ RTC_GUARDED_BY(&encoder_queue_); |
| absl::optional<VideoFrame> pending_frame_ RTC_GUARDED_BY(&encoder_queue_); |
| int64_t pending_frame_post_time_us_ RTC_GUARDED_BY(&encoder_queue_); |
| |
| VideoFrame::UpdateRect accumulated_update_rect_ |
| RTC_GUARDED_BY(&encoder_queue_); |
| bool accumulated_update_rect_is_valid_ RTC_GUARDED_BY(&encoder_queue_); |
| |
| VideoBitrateAllocationObserver* bitrate_observer_ |
| RTC_GUARDED_BY(&encoder_queue_); |
| FecControllerOverride* fec_controller_override_ |
| RTC_GUARDED_BY(&encoder_queue_); |
| absl::optional<int64_t> last_parameters_update_ms_ |
| RTC_GUARDED_BY(&encoder_queue_); |
| absl::optional<int64_t> last_encode_info_ms_ RTC_GUARDED_BY(&encoder_queue_); |
| |
| VideoEncoder::EncoderInfo encoder_info_ RTC_GUARDED_BY(&encoder_queue_); |
| absl::optional<VideoEncoder::ResolutionBitrateLimits> encoder_bitrate_limits_ |
| RTC_GUARDED_BY(&encoder_queue_); |
| VideoEncoderFactory::CodecInfo codec_info_ RTC_GUARDED_BY(&encoder_queue_); |
| VideoCodec send_codec_ RTC_GUARDED_BY(&encoder_queue_); |
| |
| FrameDropper frame_dropper_ RTC_GUARDED_BY(&encoder_queue_); |
| // If frame dropper is not force disabled, frame dropping might still be |
| // disabled if VideoEncoder::GetEncoderInfo() indicates that the encoder has a |
| // trusted rate controller. This is determined on a per-frame basis, as the |
| // encoder behavior might dynamically change. |
| bool force_disable_frame_dropper_ RTC_GUARDED_BY(&encoder_queue_); |
| RateStatistics input_framerate_ RTC_GUARDED_BY(&encoder_queue_); |
| // Incremented on worker thread whenever |frame_dropper_| determines that a |
| // frame should be dropped. Decremented on whichever thread runs |
| // OnEncodedImage(), which is only called by one thread but not necessarily |
| // the worker thread. |
| std::atomic<int> pending_frame_drops_; |
| |
| std::unique_ptr<EncoderBitrateAdjuster> bitrate_adjuster_ |
| RTC_GUARDED_BY(&encoder_queue_); |
| |
| // TODO(sprang): Change actually support keyframe per simulcast stream, or |
| // turn this into a simple bool |pending_keyframe_request_|. |
| std::vector<VideoFrameType> next_frame_types_ RTC_GUARDED_BY(&encoder_queue_); |
| |
| FrameEncodeMetadataWriter frame_encode_metadata_writer_; |
| |
| // Experiment groups parsed from field trials for realtime video ([0]) and |
| // screenshare ([1]). 0 means no group specified. Positive values are |
| // experiment group numbers incremented by 1. |
| const std::array<uint8_t, 2> experiment_groups_; |
| |
| // TODO(philipel): Remove this lock and run on |encoder_queue_| instead. |
| rtc::CriticalSection encoded_image_lock_; |
| |
| int64_t next_frame_id_ RTC_GUARDED_BY(encoded_image_lock_); |
| |
| // This array is used as a map from simulcast id to an encoder's buffer |
| // state. For every buffer of the encoder we keep track of the last frame id |
| // that updated that buffer. |
| std::array<std::array<int64_t, kMaxEncoderBuffers>, kMaxSimulcastStreams> |
| encoder_buffer_state_ RTC_GUARDED_BY(encoded_image_lock_); |
| |
| struct EncoderSwitchExperiment { |
| struct Thresholds { |
| absl::optional<DataRate> bitrate; |
| absl::optional<int> pixel_count; |
| }; |
| |
| // Codec --> switching thresholds |
| std::map<VideoCodecType, Thresholds> codec_thresholds; |
| |
| // To smooth out the target bitrate so that we don't trigger a switch |
| // too easily. |
| rtc::ExpFilter bitrate_filter{1.0}; |
| |
| // Codec/implementation to switch to |
| std::string to_codec; |
| absl::optional<std::string> to_param; |
| absl::optional<std::string> to_value; |
| |
| // Thresholds for the currently used codecs. |
| Thresholds current_thresholds; |
| |
| // Updates the |bitrate_filter|, so not const. |
| bool IsBitrateBelowThreshold(const DataRate& target_bitrate); |
| bool IsPixelCountBelowThreshold(int pixel_count) const; |
| void SetCodec(VideoCodecType codec); |
| }; |
| |
| EncoderSwitchExperiment ParseEncoderSwitchFieldTrial() const; |
| |
| EncoderSwitchExperiment encoder_switch_experiment_ |
| RTC_GUARDED_BY(&encoder_queue_); |
| |
| // An encoder switch is only requested once, this variable is used to keep |
| // track of whether a request has been made or not. |
| bool encoder_switch_requested_ RTC_GUARDED_BY(&encoder_queue_); |
| |
| // All public methods are proxied to |encoder_queue_|. It must must be |
| // destroyed first to make sure no tasks are run that use other members. |
| rtc::TaskQueue encoder_queue_; |
| |
| RTC_DISALLOW_COPY_AND_ASSIGN(VideoStreamEncoder); |
| }; |
| |
| } // namespace webrtc |
| |
| #endif // VIDEO_VIDEO_STREAM_ENCODER_H_ |