1 /* 2 * Copyright (c) 2011 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_VIDEO_CODING_MAIN_SOURCE_TIMING_H_ 12 #define WEBRTC_MODULES_VIDEO_CODING_MAIN_SOURCE_TIMING_H_ 13 14 #include "webrtc/base/thread_annotations.h" 15 #include "webrtc/modules/video_coding/main/source/codec_timer.h" 16 #include "webrtc/system_wrappers/interface/critical_section_wrapper.h" 17 #include "webrtc/typedefs.h" 18 19 namespace webrtc { 20 21 class Clock; 22 class TimestampExtrapolator; 23 24 class VCMTiming { 25 public: 26 // The primary timing component should be passed 27 // if this is the dual timing component. 28 VCMTiming(Clock* clock, 29 VCMTiming* master_timing = NULL); 30 ~VCMTiming(); 31 32 // Resets the timing to the initial state. 33 void Reset(); 34 void ResetDecodeTime(); 35 36 // Set the amount of time needed to render an image. Defaults to 10 ms. 37 void set_render_delay(uint32_t render_delay_ms); 38 39 // Set the minimum time the video must be delayed on the receiver to 40 // get the desired jitter buffer level. 41 void SetJitterDelay(uint32_t required_delay_ms); 42 43 // Set the minimum playout delay required to sync video with audio. 44 void set_min_playout_delay(uint32_t min_playout_delay); 45 46 // Increases or decreases the current delay to get closer to the target delay. 47 // Calculates how long it has been since the previous call to this function, 48 // and increases/decreases the delay in proportion to the time difference. 49 void UpdateCurrentDelay(uint32_t frame_timestamp); 50 51 // Increases or decreases the current delay to get closer to the target delay. 52 // Given the actual decode time in ms and the render time in ms for a frame, 53 // this function calculates how late the frame is and increases the delay 54 // accordingly. 55 void UpdateCurrentDelay(int64_t render_time_ms, 56 int64_t actual_decode_time_ms); 57 58 // Stops the decoder timer, should be called when the decoder returns a frame 59 // or when the decoded frame callback is called. 60 int32_t StopDecodeTimer(uint32_t time_stamp, 61 int64_t start_time_ms, 62 int64_t now_ms); 63 64 // Used to report that a frame is passed to decoding. Updates the timestamp 65 // filter which is used to map between timestamps and receiver system time. 66 void IncomingTimestamp(uint32_t time_stamp, int64_t last_packet_time_ms); 67 // Returns the receiver system time when the frame with timestamp 68 // frame_timestamp should be rendered, assuming that the system time currently 69 // is now_ms. 70 int64_t RenderTimeMs(uint32_t frame_timestamp, int64_t now_ms) const; 71 72 // Returns the maximum time in ms that we can wait for a frame to become 73 // complete before we must pass it to the decoder. 74 uint32_t MaxWaitingTime(int64_t render_time_ms, int64_t now_ms) const; 75 76 // Returns the current target delay which is required delay + decode time + 77 // render delay. 78 uint32_t TargetVideoDelay() const; 79 80 // Calculates whether or not there is enough time to decode a frame given a 81 // certain amount of processing time. 82 bool EnoughTimeToDecode(uint32_t available_processing_time_ms) const; 83 84 // Return current timing information. 85 void GetTimings(int* decode_ms, 86 int* max_decode_ms, 87 int* current_delay_ms, 88 int* target_delay_ms, 89 int* jitter_buffer_ms, 90 int* min_playout_delay_ms, 91 int* render_delay_ms) const; 92 93 enum { kDefaultRenderDelayMs = 10 }; 94 enum { kDelayMaxChangeMsPerS = 100 }; 95 96 protected: 97 int32_t MaxDecodeTimeMs(FrameType frame_type = kVideoFrameDelta) const 98 EXCLUSIVE_LOCKS_REQUIRED(crit_sect_); 99 int64_t RenderTimeMsInternal(uint32_t frame_timestamp, int64_t now_ms) const 100 EXCLUSIVE_LOCKS_REQUIRED(crit_sect_); 101 uint32_t TargetDelayInternal() const EXCLUSIVE_LOCKS_REQUIRED(crit_sect_); 102 103 private: 104 CriticalSectionWrapper* crit_sect_; 105 Clock* const clock_; 106 bool master_ GUARDED_BY(crit_sect_); 107 TimestampExtrapolator* ts_extrapolator_ GUARDED_BY(crit_sect_); 108 VCMCodecTimer codec_timer_ GUARDED_BY(crit_sect_); 109 uint32_t render_delay_ms_ GUARDED_BY(crit_sect_); 110 uint32_t min_playout_delay_ms_ GUARDED_BY(crit_sect_); 111 uint32_t jitter_delay_ms_ GUARDED_BY(crit_sect_); 112 uint32_t current_delay_ms_ GUARDED_BY(crit_sect_); 113 int last_decode_ms_ GUARDED_BY(crit_sect_); 114 uint32_t prev_frame_timestamp_ GUARDED_BY(crit_sect_); 115 }; 116 } // namespace webrtc 117 118 #endif // WEBRTC_MODULES_VIDEO_CODING_MAIN_SOURCE_TIMING_H_ 119