1 /* 2 * Copyright (c) 2020 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 VIDEO_RTP_STREAMS_SYNCHRONIZER2_H_ 12 #define VIDEO_RTP_STREAMS_SYNCHRONIZER2_H_ 13 14 #include <memory> 15 16 #include "rtc_base/synchronization/sequence_checker.h" 17 #include "rtc_base/task_queue.h" 18 #include "rtc_base/task_utils/repeating_task.h" 19 #include "video/stream_synchronization.h" 20 21 namespace webrtc { 22 23 class Syncable; 24 25 namespace internal { 26 27 // RtpStreamsSynchronizer is responsible for synchronizing audio and video for 28 // a given audio receive stream and video receive stream. 29 class RtpStreamsSynchronizer { 30 public: 31 RtpStreamsSynchronizer(TaskQueueBase* main_queue, Syncable* syncable_video); 32 ~RtpStreamsSynchronizer(); 33 34 void ConfigureSync(Syncable* syncable_audio); 35 36 // Gets the estimated playout NTP timestamp for the video frame with 37 // |rtp_timestamp| and the sync offset between the current played out audio 38 // frame and the video frame. Returns true on success, false otherwise. 39 // The |estimated_freq_khz| is the frequency used in the RTP to NTP timestamp 40 // conversion. 41 bool GetStreamSyncOffsetInMs(uint32_t rtp_timestamp, 42 int64_t render_time_ms, 43 int64_t* video_playout_ntp_ms, 44 int64_t* stream_offset_ms, 45 double* estimated_freq_khz) const; 46 47 private: 48 void UpdateDelay(); 49 50 TaskQueueBase* const task_queue_; 51 52 // Used to check if we're running on the main thread/task queue. 53 // The reason we currently don't use RTC_DCHECK_RUN_ON(task_queue_) is because 54 // we might be running on an rtc::Thread implementation of TaskQueue, which 55 // does not consistently set itself as the active TaskQueue. 56 // Instead, we rely on a SequenceChecker for now. 57 SequenceChecker main_checker_; 58 59 Syncable* const syncable_video_; 60 61 Syncable* syncable_audio_ RTC_GUARDED_BY(main_checker_) = nullptr; 62 std::unique_ptr<StreamSynchronization> sync_ RTC_GUARDED_BY(main_checker_); 63 StreamSynchronization::Measurements audio_measurement_ 64 RTC_GUARDED_BY(main_checker_); 65 StreamSynchronization::Measurements video_measurement_ 66 RTC_GUARDED_BY(main_checker_); 67 RepeatingTaskHandle repeating_task_ RTC_GUARDED_BY(main_checker_); 68 int64_t last_stats_log_ms_ RTC_GUARDED_BY(&main_checker_); 69 }; 70 71 } // namespace internal 72 } // namespace webrtc 73 74 #endif // VIDEO_RTP_STREAMS_SYNCHRONIZER2_H_ 75