Line data    Source code

       1             : /*
       2             :  *  Copyright (c) 2016 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_MODULES_RTP_RTCP_SOURCE_PLAYOUT_DELAY_ORACLE_H_
      12             : #define WEBRTC_MODULES_RTP_RTCP_SOURCE_PLAYOUT_DELAY_ORACLE_H_
      13             : 
      14             : #include <stdint.h>
      15             : 
      16             : #include "webrtc/base/criticalsection.h"
      17             : #include "webrtc/base/thread_annotations.h"
      18             : #include "webrtc/modules/include/module_common_types.h"
      19             : #include "webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h"
      20             : 
      21             : namespace webrtc {
      22             : 
      23             : // This class tracks the application requests to limit minimum and maximum
      24             : // playout delay and makes a decision on whether the current RTP frame
      25             : // should include the playout out delay extension header.
      26             : //
      27             : //  Playout delay can be defined in terms of capture and render time as follows:
      28             : //
      29             : // Render time = Capture time in receiver time + playout delay
      30             : //
      31             : // The application specifies a minimum and maximum limit for the playout delay
      32             : // which are both communicated to the receiver and the receiver can adapt
      33             : // the playout delay within this range based on observed network jitter.
      34             : class PlayoutDelayOracle {
      35             :  public:
      36             :   PlayoutDelayOracle();
      37             :   ~PlayoutDelayOracle();
      38             : 
      39             :   // Returns true if the current frame should include the playout delay
      40             :   // extension
      41           0 :   bool send_playout_delay() const {
      42           0 :     rtc::CritScope lock(&crit_sect_);
      43           0 :     return send_playout_delay_;
      44             :   }
      45             : 
      46             :   // Returns current playout delay.
      47           0 :   PlayoutDelay playout_delay() const {
      48           0 :     rtc::CritScope lock(&crit_sect_);
      49           0 :     return playout_delay_;
      50             :   }
      51             : 
      52             :   // Updates the application requested playout delay, current ssrc
      53             :   // and the current sequence number.
      54             :   void UpdateRequest(uint32_t ssrc,
      55             :                      PlayoutDelay playout_delay,
      56             :                      uint16_t seq_num);
      57             : 
      58             :   void OnReceivedRtcpReportBlocks(const ReportBlockList& report_blocks);
      59             : 
      60             :  private:
      61             :   // The playout delay information is updated from the encoder thread(s).
      62             :   // The sequence number feedback is updated from the worker thread.
      63             :   // Guards access to data across multiple threads.
      64             :   rtc::CriticalSection crit_sect_;
      65             :   // The current highest sequence number on which playout delay has been sent.
      66             :   int64_t high_sequence_number_ GUARDED_BY(crit_sect_);
      67             :   // Indicates whether the playout delay should go on the next frame.
      68             :   bool send_playout_delay_ GUARDED_BY(crit_sect_);
      69             :   // Sender ssrc.
      70             :   uint32_t ssrc_ GUARDED_BY(crit_sect_);
      71             :   // Sequence number unwrapper.
      72             :   SequenceNumberUnwrapper unwrapper_ GUARDED_BY(crit_sect_);
      73             :   // Playout delay values on the next frame if |send_playout_delay_| is set.
      74             :   PlayoutDelay playout_delay_ GUARDED_BY(crit_sect_);
      75             : 
      76             :   RTC_DISALLOW_COPY_AND_ASSIGN(PlayoutDelayOracle);
      77             : };
      78             : 
      79             : }  // namespace webrtc
      80             : 
      81             : #endif  // WEBRTC_MODULES_RTP_RTCP_SOURCE_PLAYOUT_DELAY_ORACLE_H_