Line data    Source code

       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             : #include "webrtc/modules/video_coding/codec_timer.h"
      12             : 
      13             : namespace webrtc {
      14             : 
      15             : namespace {
      16             : 
      17             : // The first kIgnoredSampleCount samples will be ignored.
      18             : const int kIgnoredSampleCount = 5;
      19             : // Return the |kPercentile| value in RequiredDecodeTimeMs().
      20             : const float kPercentile = 0.95f;
      21             : // The window size in ms.
      22             : const int64_t kTimeLimitMs = 10000;
      23             : 
      24             : }  // anonymous namespace
      25             : 
      26           0 : VCMCodecTimer::VCMCodecTimer()
      27           0 :     : ignored_sample_count_(0), filter_(kPercentile) {}
      28             : 
      29           0 : void VCMCodecTimer::AddTiming(int64_t decode_time_ms, int64_t now_ms) {
      30             :   // Ignore the first |kIgnoredSampleCount| samples.
      31           0 :   if (ignored_sample_count_ < kIgnoredSampleCount) {
      32           0 :     ++ignored_sample_count_;
      33           0 :     return;
      34             :   }
      35             : 
      36             :   // Insert new decode time value.
      37           0 :   filter_.Insert(decode_time_ms);
      38           0 :   history_.emplace(decode_time_ms, now_ms);
      39             : 
      40             :   // Pop old decode time values.
      41           0 :   while (!history_.empty() &&
      42           0 :          now_ms - history_.front().sample_time_ms > kTimeLimitMs) {
      43           0 :     filter_.Erase(history_.front().decode_time_ms);
      44           0 :     history_.pop();
      45             :   }
      46             : }
      47             : 
      48             : // Get the 95th percentile observed decode time within a time window.
      49           0 : int64_t VCMCodecTimer::RequiredDecodeTimeMs() const {
      50           0 :   return filter_.GetPercentileValue();
      51             : }
      52             : 
      53           0 : VCMCodecTimer::Sample::Sample(int64_t decode_time_ms, int64_t sample_time_ms)
      54           0 :     : decode_time_ms(decode_time_ms), sample_time_ms(sample_time_ms) {}
      55             : 
      56             : }  // namespace webrtc