webrtc/modules/video_coding/timing.cc - src - Git at Google

 /*
  *  Copyright (c) 2011 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.
  */

 #include "webrtc/modules/video_coding/timing.h"

 #include <algorithm>

 #include "webrtc/modules/video_coding/internal_defines.h"
 #include "webrtc/modules/video_coding/jitter_buffer_common.h"
 #include "webrtc/system_wrappers/include/clock.h"
 #include "webrtc/system_wrappers/include/metrics.h"
 #include "webrtc/system_wrappers/include/timestamp_extrapolator.h"

 namespace webrtc {

 VCMTiming::VCMTiming(Clock* clock, VCMTiming* master_timing)
     : crit_sect_(CriticalSectionWrapper::CreateCriticalSection()),
       clock_(clock),
       master_(false),
       ts_extrapolator_(),
       codec_timer_(new VCMCodecTimer()),
       render_delay_ms_(kDefaultRenderDelayMs),
       min_playout_delay_ms_(0),
       max_playout_delay_ms_(10000),
       jitter_delay_ms_(0),
       current_delay_ms_(0),
       last_decode_ms_(0),
       prev_frame_timestamp_(0),
       num_decoded_frames_(0),
       num_delayed_decoded_frames_(0),
       first_decoded_frame_ms_(-1),
       sum_missed_render_deadline_ms_(0) {
   if (master_timing == NULL) {
     master_ = true;
     ts_extrapolator_ = new TimestampExtrapolator(clock_->TimeInMilliseconds());
   } else {
     ts_extrapolator_ = master_timing->ts_extrapolator_;
   }
 }

 VCMTiming::~VCMTiming() {
   UpdateHistograms();
   if (master_) {
     delete ts_extrapolator_;
   }
   delete crit_sect_;
 }

 void VCMTiming::UpdateHistograms() const {
   CriticalSectionScoped cs(crit_sect_);
   if (num_decoded_frames_ == 0) {
     return;
   }
   int64_t elapsed_sec =
       (clock_->TimeInMilliseconds() - first_decoded_frame_ms_) / 1000;
   if (elapsed_sec < metrics::kMinRunTimeInSeconds) {
     return;
   }
   RTC_HISTOGRAM_COUNTS_100(
       "WebRTC.Video.DecodedFramesPerSecond",
       static_cast<int>((num_decoded_frames_ / elapsed_sec) + 0.5f));
   RTC_HISTOGRAM_PERCENTAGE(
       "WebRTC.Video.DelayedFramesToRenderer",
       num_delayed_decoded_frames_ * 100 / num_decoded_frames_);
   if (num_delayed_decoded_frames_ > 0) {
     RTC_HISTOGRAM_COUNTS_1000(
         "WebRTC.Video.DelayedFramesToRenderer_AvgDelayInMs",
         sum_missed_render_deadline_ms_ / num_delayed_decoded_frames_);
   }
 }

 void VCMTiming::Reset() {
   CriticalSectionScoped cs(crit_sect_);
   ts_extrapolator_->Reset(clock_->TimeInMilliseconds());
   codec_timer_.reset(new VCMCodecTimer());
   render_delay_ms_ = kDefaultRenderDelayMs;
   min_playout_delay_ms_ = 0;
   jitter_delay_ms_ = 0;
   current_delay_ms_ = 0;
   prev_frame_timestamp_ = 0;
 }

 void VCMTiming::ResetDecodeTime() {
   CriticalSectionScoped lock(crit_sect_);
   codec_timer_.reset(new VCMCodecTimer());
 }

 void VCMTiming::set_render_delay(int render_delay_ms) {
   CriticalSectionScoped cs(crit_sect_);
   render_delay_ms_ = render_delay_ms;
 }

 void VCMTiming::set_min_playout_delay(int min_playout_delay_ms) {
   CriticalSectionScoped cs(crit_sect_);
   min_playout_delay_ms_ = min_playout_delay_ms;
 }

 int VCMTiming::min_playout_delay() {
   CriticalSectionScoped cs(crit_sect_);
   return min_playout_delay_ms_;
 }

 void VCMTiming::set_max_playout_delay(int max_playout_delay_ms) {
   CriticalSectionScoped cs(crit_sect_);
   max_playout_delay_ms_ = max_playout_delay_ms;
 }

 int VCMTiming::max_playout_delay() {
   CriticalSectionScoped cs(crit_sect_);
   return max_playout_delay_ms_;
 }

 void VCMTiming::SetJitterDelay(int jitter_delay_ms) {
   CriticalSectionScoped cs(crit_sect_);
   if (jitter_delay_ms != jitter_delay_ms_) {
     jitter_delay_ms_ = jitter_delay_ms;
     // When in initial state, set current delay to minimum delay.
     if (current_delay_ms_ == 0) {
       current_delay_ms_ = jitter_delay_ms_;
     }
   }
 }

 void VCMTiming::UpdateCurrentDelay(uint32_t frame_timestamp) {
   CriticalSectionScoped cs(crit_sect_);
   int target_delay_ms = TargetDelayInternal();

   if (current_delay_ms_ == 0) {
     // Not initialized, set current delay to target.
     current_delay_ms_ = target_delay_ms;
   } else if (target_delay_ms != current_delay_ms_) {
     int64_t delay_diff_ms =
         static_cast<int64_t>(target_delay_ms) - current_delay_ms_;
     // Never change the delay with more than 100 ms every second. If we're
     // changing the delay in too large steps we will get noticeable freezes. By
     // limiting the change we can increase the delay in smaller steps, which
     // will be experienced as the video is played in slow motion. When lowering
     // the delay the video will be played at a faster pace.
     int64_t max_change_ms = 0;
     if (frame_timestamp < 0x0000ffff && prev_frame_timestamp_ > 0xffff0000) {
       // wrap
       max_change_ms = kDelayMaxChangeMsPerS *
                       (frame_timestamp + (static_cast<int64_t>(1) << 32) -
                        prev_frame_timestamp_) /
                       90000;
     } else {
       max_change_ms = kDelayMaxChangeMsPerS *
                       (frame_timestamp - prev_frame_timestamp_) / 90000;
     }
     if (max_change_ms <= 0) {
       // Any changes less than 1 ms are truncated and
       // will be postponed. Negative change will be due
       // to reordering and should be ignored.
       return;
     }
     delay_diff_ms = std::max(delay_diff_ms, -max_change_ms);
     delay_diff_ms = std::min(delay_diff_ms, max_change_ms);

     current_delay_ms_ = current_delay_ms_ + delay_diff_ms;
   }
   prev_frame_timestamp_ = frame_timestamp;
 }

 void VCMTiming::UpdateCurrentDelay(int64_t render_time_ms,
                                    int64_t actual_decode_time_ms) {
   CriticalSectionScoped cs(crit_sect_);
   uint32_t target_delay_ms = TargetDelayInternal();
   int64_t delayed_ms =
       actual_decode_time_ms -
       (render_time_ms - RequiredDecodeTimeMs() - render_delay_ms_);
   if (delayed_ms < 0) {
     return;
   }
   if (current_delay_ms_ + delayed_ms <= target_delay_ms) {
     current_delay_ms_ += delayed_ms;
   } else {
     current_delay_ms_ = target_delay_ms;
   }
 }

 int32_t VCMTiming::StopDecodeTimer(uint32_t time_stamp,
                                    int32_t decode_time_ms,
                                    int64_t now_ms,
                                    int64_t render_time_ms) {
   CriticalSectionScoped cs(crit_sect_);
   codec_timer_->AddTiming(decode_time_ms, now_ms);
   assert(decode_time_ms >= 0);
   last_decode_ms_ = decode_time_ms;

   // Update stats.
   ++num_decoded_frames_;
   if (num_decoded_frames_ == 1) {
     first_decoded_frame_ms_ = now_ms;
   }
   int time_until_rendering_ms = render_time_ms - render_delay_ms_ - now_ms;
   if (time_until_rendering_ms < 0) {
     sum_missed_render_deadline_ms_ += -time_until_rendering_ms;
     ++num_delayed_decoded_frames_;
   }
   return 0;
 }

 void VCMTiming::IncomingTimestamp(uint32_t time_stamp, int64_t now_ms) {
   CriticalSectionScoped cs(crit_sect_);
   ts_extrapolator_->Update(now_ms, time_stamp);
 }

 int64_t VCMTiming::RenderTimeMs(uint32_t frame_timestamp,
                                 int64_t now_ms) const {
   CriticalSectionScoped cs(crit_sect_);
   const int64_t render_time_ms = RenderTimeMsInternal(frame_timestamp, now_ms);
   return render_time_ms;
 }

 int64_t VCMTiming::RenderTimeMsInternal(uint32_t frame_timestamp,
                                         int64_t now_ms) const {
   int64_t estimated_complete_time_ms =
       ts_extrapolator_->ExtrapolateLocalTime(frame_timestamp);
   if (estimated_complete_time_ms == -1) {
     estimated_complete_time_ms = now_ms;
   }

   if (min_playout_delay_ms_ == 0 && max_playout_delay_ms_ == 0) {
     // Render as soon as possible
     return now_ms;
   }

   // Make sure the actual delay stays in the range of |min_playout_delay_ms_|
   // and |max_playout_delay_ms_|.
   int actual_delay = std::max(current_delay_ms_, min_playout_delay_ms_);
   actual_delay = std::min(actual_delay, max_playout_delay_ms_);
   return estimated_complete_time_ms + actual_delay;
 }

 // Must be called from inside a critical section.
 int VCMTiming::RequiredDecodeTimeMs() const {
   const int decode_time_ms = codec_timer_->RequiredDecodeTimeMs();
   assert(decode_time_ms >= 0);
   return decode_time_ms;
 }

 uint32_t VCMTiming::MaxWaitingTime(int64_t render_time_ms,
                                    int64_t now_ms) const {
   CriticalSectionScoped cs(crit_sect_);

   const int64_t max_wait_time_ms =
       render_time_ms - now_ms - RequiredDecodeTimeMs() - render_delay_ms_;

   if (max_wait_time_ms < 0) {
     return 0;
   }
   return static_cast<uint32_t>(max_wait_time_ms);
 }

 bool VCMTiming::EnoughTimeToDecode(
     uint32_t available_processing_time_ms) const {
   CriticalSectionScoped cs(crit_sect_);
   int64_t required_decode_time_ms = RequiredDecodeTimeMs();
   if (required_decode_time_ms < 0) {
     // Haven't decoded any frames yet, try decoding one to get an estimate
     // of the decode time.
     return true;
   } else if (required_decode_time_ms == 0) {
     // Decode time is less than 1, set to 1 for now since
     // we don't have any better precision. Count ticks later?
     required_decode_time_ms = 1;
   }
   return static_cast<int64_t>(available_processing_time_ms) -
              required_decode_time_ms >
          0;
 }

 int VCMTiming::TargetVideoDelay() const {
   CriticalSectionScoped cs(crit_sect_);
   return TargetDelayInternal();
 }

 int VCMTiming::TargetDelayInternal() const {
   return std::max(min_playout_delay_ms_,
                   jitter_delay_ms_ + RequiredDecodeTimeMs() + render_delay_ms_);
 }

 void VCMTiming::GetTimings(int* decode_ms,
                            int* max_decode_ms,
                            int* current_delay_ms,
                            int* target_delay_ms,
                            int* jitter_buffer_ms,
                            int* min_playout_delay_ms,
                            int* render_delay_ms) const {
   CriticalSectionScoped cs(crit_sect_);
   *decode_ms = last_decode_ms_;
   *max_decode_ms = RequiredDecodeTimeMs();
   *current_delay_ms = current_delay_ms_;
   *target_delay_ms = TargetDelayInternal();
   *jitter_buffer_ms = jitter_delay_ms_;
   *min_playout_delay_ms = min_playout_delay_ms_;
   *render_delay_ms = render_delay_ms_;
 }

 }  // namespace webrtc
	/*
	* Copyright (c) 2011 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.
	*/

	#include "webrtc/modules/video_coding/timing.h"

	#include <algorithm>

	#include "webrtc/modules/video_coding/internal_defines.h"
	#include "webrtc/modules/video_coding/jitter_buffer_common.h"
	#include "webrtc/system_wrappers/include/clock.h"
	#include "webrtc/system_wrappers/include/metrics.h"
	#include "webrtc/system_wrappers/include/timestamp_extrapolator.h"

	namespace webrtc {

	VCMTiming::VCMTiming(Clock* clock, VCMTiming* master_timing)
	: crit_sect_(CriticalSectionWrapper::CreateCriticalSection()),
	clock_(clock),
	master_(false),
	ts_extrapolator_(),
	codec_timer_(new VCMCodecTimer()),
	render_delay_ms_(kDefaultRenderDelayMs),
	min_playout_delay_ms_(0),
	max_playout_delay_ms_(10000),
	jitter_delay_ms_(0),
	current_delay_ms_(0),
	last_decode_ms_(0),
	prev_frame_timestamp_(0),
	num_decoded_frames_(0),
	num_delayed_decoded_frames_(0),
	first_decoded_frame_ms_(-1),
	sum_missed_render_deadline_ms_(0) {
	if (master_timing == NULL) {
	master_ = true;
	ts_extrapolator_ = new TimestampExtrapolator(clock_->TimeInMilliseconds());
	} else {
	ts_extrapolator_ = master_timing->ts_extrapolator_;
	}
	}

	VCMTiming::~VCMTiming() {
	UpdateHistograms();
	if (master_) {
	delete ts_extrapolator_;
	}
	delete crit_sect_;
	}

	void VCMTiming::UpdateHistograms() const {
	CriticalSectionScoped cs(crit_sect_);
	if (num_decoded_frames_ == 0) {
	return;
	}
	int64_t elapsed_sec =
	(clock_->TimeInMilliseconds() - first_decoded_frame_ms_) / 1000;
	if (elapsed_sec < metrics::kMinRunTimeInSeconds) {
	return;
	}
	RTC_HISTOGRAM_COUNTS_100(
	"WebRTC.Video.DecodedFramesPerSecond",
	static_cast<int>((num_decoded_frames_ / elapsed_sec) + 0.5f));
	RTC_HISTOGRAM_PERCENTAGE(
	"WebRTC.Video.DelayedFramesToRenderer",
	num_delayed_decoded_frames_ * 100 / num_decoded_frames_);
	if (num_delayed_decoded_frames_ > 0) {
	RTC_HISTOGRAM_COUNTS_1000(
	"WebRTC.Video.DelayedFramesToRenderer_AvgDelayInMs",
	sum_missed_render_deadline_ms_ / num_delayed_decoded_frames_);
	}
	}

	void VCMTiming::Reset() {
	CriticalSectionScoped cs(crit_sect_);
	ts_extrapolator_->Reset(clock_->TimeInMilliseconds());
	codec_timer_.reset(new VCMCodecTimer());
	render_delay_ms_ = kDefaultRenderDelayMs;
	min_playout_delay_ms_ = 0;
	jitter_delay_ms_ = 0;
	current_delay_ms_ = 0;
	prev_frame_timestamp_ = 0;
	}

	void VCMTiming::ResetDecodeTime() {
	CriticalSectionScoped lock(crit_sect_);
	codec_timer_.reset(new VCMCodecTimer());
	}

	void VCMTiming::set_render_delay(int render_delay_ms) {
	CriticalSectionScoped cs(crit_sect_);
	render_delay_ms_ = render_delay_ms;
	}

	void VCMTiming::set_min_playout_delay(int min_playout_delay_ms) {
	CriticalSectionScoped cs(crit_sect_);
	min_playout_delay_ms_ = min_playout_delay_ms;
	}

	int VCMTiming::min_playout_delay() {
	CriticalSectionScoped cs(crit_sect_);
	return min_playout_delay_ms_;
	}

	void VCMTiming::set_max_playout_delay(int max_playout_delay_ms) {
	CriticalSectionScoped cs(crit_sect_);
	max_playout_delay_ms_ = max_playout_delay_ms;
	}

	int VCMTiming::max_playout_delay() {
	CriticalSectionScoped cs(crit_sect_);
	return max_playout_delay_ms_;
	}

	void VCMTiming::SetJitterDelay(int jitter_delay_ms) {
	CriticalSectionScoped cs(crit_sect_);
	if (jitter_delay_ms != jitter_delay_ms_) {
	jitter_delay_ms_ = jitter_delay_ms;
	// When in initial state, set current delay to minimum delay.
	if (current_delay_ms_ == 0) {
	current_delay_ms_ = jitter_delay_ms_;
	}
	}
	}

	void VCMTiming::UpdateCurrentDelay(uint32_t frame_timestamp) {
	CriticalSectionScoped cs(crit_sect_);
	int target_delay_ms = TargetDelayInternal();

	if (current_delay_ms_ == 0) {
	// Not initialized, set current delay to target.
	current_delay_ms_ = target_delay_ms;
	} else if (target_delay_ms != current_delay_ms_) {
	int64_t delay_diff_ms =
	static_cast<int64_t>(target_delay_ms) - current_delay_ms_;
	// Never change the delay with more than 100 ms every second. If we're
	// changing the delay in too large steps we will get noticeable freezes. By
	// limiting the change we can increase the delay in smaller steps, which
	// will be experienced as the video is played in slow motion. When lowering
	// the delay the video will be played at a faster pace.
	int64_t max_change_ms = 0;
	if (frame_timestamp < 0x0000ffff && prev_frame_timestamp_ > 0xffff0000) {
	// wrap
	max_change_ms = kDelayMaxChangeMsPerS *
	(frame_timestamp + (static_cast<int64_t>(1) << 32) -
	prev_frame_timestamp_) /
	90000;
	} else {
	max_change_ms = kDelayMaxChangeMsPerS *
	(frame_timestamp - prev_frame_timestamp_) / 90000;
	}
	if (max_change_ms <= 0) {
	// Any changes less than 1 ms are truncated and
	// will be postponed. Negative change will be due
	// to reordering and should be ignored.
	return;
	}
	delay_diff_ms = std::max(delay_diff_ms, -max_change_ms);
	delay_diff_ms = std::min(delay_diff_ms, max_change_ms);

	current_delay_ms_ = current_delay_ms_ + delay_diff_ms;
	}
	prev_frame_timestamp_ = frame_timestamp;
	}

	void VCMTiming::UpdateCurrentDelay(int64_t render_time_ms,
	int64_t actual_decode_time_ms) {
	CriticalSectionScoped cs(crit_sect_);
	uint32_t target_delay_ms = TargetDelayInternal();
	int64_t delayed_ms =
	actual_decode_time_ms -
	(render_time_ms - RequiredDecodeTimeMs() - render_delay_ms_);
	if (delayed_ms < 0) {
	return;
	}
	if (current_delay_ms_ + delayed_ms <= target_delay_ms) {
	current_delay_ms_ += delayed_ms;
	} else {
	current_delay_ms_ = target_delay_ms;
	}
	}

	int32_t VCMTiming::StopDecodeTimer(uint32_t time_stamp,
	int32_t decode_time_ms,
	int64_t now_ms,
	int64_t render_time_ms) {
	CriticalSectionScoped cs(crit_sect_);
	codec_timer_->AddTiming(decode_time_ms, now_ms);
	assert(decode_time_ms >= 0);
	last_decode_ms_ = decode_time_ms;

	// Update stats.
	++num_decoded_frames_;
	if (num_decoded_frames_ == 1) {
	first_decoded_frame_ms_ = now_ms;
	}
	int time_until_rendering_ms = render_time_ms - render_delay_ms_ - now_ms;
	if (time_until_rendering_ms < 0) {
	sum_missed_render_deadline_ms_ += -time_until_rendering_ms;
	++num_delayed_decoded_frames_;
	}
	return 0;
	}

	void VCMTiming::IncomingTimestamp(uint32_t time_stamp, int64_t now_ms) {
	CriticalSectionScoped cs(crit_sect_);
	ts_extrapolator_->Update(now_ms, time_stamp);
	}

	int64_t VCMTiming::RenderTimeMs(uint32_t frame_timestamp,
	int64_t now_ms) const {
	CriticalSectionScoped cs(crit_sect_);
	const int64_t render_time_ms = RenderTimeMsInternal(frame_timestamp, now_ms);
	return render_time_ms;
	}

	int64_t VCMTiming::RenderTimeMsInternal(uint32_t frame_timestamp,
	int64_t now_ms) const {
	int64_t estimated_complete_time_ms =
	ts_extrapolator_->ExtrapolateLocalTime(frame_timestamp);
	if (estimated_complete_time_ms == -1) {
	estimated_complete_time_ms = now_ms;
	}

	if (min_playout_delay_ms_ == 0 && max_playout_delay_ms_ == 0) {
	// Render as soon as possible
	return now_ms;
	}

	// Make sure the actual delay stays in the range of \|min_playout_delay_ms_\|
	// and \|max_playout_delay_ms_\|.
	int actual_delay = std::max(current_delay_ms_, min_playout_delay_ms_);
	actual_delay = std::min(actual_delay, max_playout_delay_ms_);
	return estimated_complete_time_ms + actual_delay;
	}

	// Must be called from inside a critical section.
	int VCMTiming::RequiredDecodeTimeMs() const {
	const int decode_time_ms = codec_timer_->RequiredDecodeTimeMs();
	assert(decode_time_ms >= 0);
	return decode_time_ms;
	}

	uint32_t VCMTiming::MaxWaitingTime(int64_t render_time_ms,
	int64_t now_ms) const {
	CriticalSectionScoped cs(crit_sect_);

	const int64_t max_wait_time_ms =
	render_time_ms - now_ms - RequiredDecodeTimeMs() - render_delay_ms_;

	if (max_wait_time_ms < 0) {
	return 0;
	}
	return static_cast<uint32_t>(max_wait_time_ms);
	}

	bool VCMTiming::EnoughTimeToDecode(
	uint32_t available_processing_time_ms) const {
	CriticalSectionScoped cs(crit_sect_);
	int64_t required_decode_time_ms = RequiredDecodeTimeMs();
	if (required_decode_time_ms < 0) {
	// Haven't decoded any frames yet, try decoding one to get an estimate
	// of the decode time.
	return true;
	} else if (required_decode_time_ms == 0) {
	// Decode time is less than 1, set to 1 for now since
	// we don't have any better precision. Count ticks later?
	required_decode_time_ms = 1;
	}
	return static_cast<int64_t>(available_processing_time_ms) -
	required_decode_time_ms >
	0;
	}

	int VCMTiming::TargetVideoDelay() const {
	CriticalSectionScoped cs(crit_sect_);
	return TargetDelayInternal();
	}

	int VCMTiming::TargetDelayInternal() const {
	return std::max(min_playout_delay_ms_,
	jitter_delay_ms_ + RequiredDecodeTimeMs() + render_delay_ms_);
	}

	void VCMTiming::GetTimings(int* decode_ms,
	int* max_decode_ms,
	int* current_delay_ms,
	int* target_delay_ms,
	int* jitter_buffer_ms,
	int* min_playout_delay_ms,
	int* render_delay_ms) const {
	CriticalSectionScoped cs(crit_sect_);
	*decode_ms = last_decode_ms_;
	*max_decode_ms = RequiredDecodeTimeMs();
	*current_delay_ms = current_delay_ms_;
	*target_delay_ms = TargetDelayInternal();
	*jitter_buffer_ms = jitter_delay_ms_;
	*min_playout_delay_ms = min_playout_delay_ms_;
	*render_delay_ms = render_delay_ms_;
	}

	} // namespace webrtc