Report max interframe delay over window insdead of interframe delay sum

webrtc/video/receive_statistics_proxy.h

 /*
  *  Copyright (c) 2013 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.
  */
 
 #ifndef WEBRTC_VIDEO_RECEIVE_STATISTICS_PROXY_H_
 #define WEBRTC_VIDEO_RECEIVE_STATISTICS_PROXY_H_
 
+#include <deque>
 #include <map>
 #include <string>
+#include <utility>
 
 #include "webrtc/common_types.h"
 #include "webrtc/common_video/include/frame_callback.h"
 #include "webrtc/modules/video_coding/include/video_coding_defines.h"
 #include "webrtc/rtc_base/criticalsection.h"
 #include "webrtc/rtc_base/rate_statistics.h"
 #include "webrtc/rtc_base/ratetracker.h"
 #include "webrtc/rtc_base/thread_annotations.h"
 #include "webrtc/video/quality_threshold.h"
 #include "webrtc/video/report_block_stats.h"
@@ skipping 70 matching lines @@
     int Avg(int64_t min_required_samples) const;
     void Reset();
 
    private:
     int64_t sum;
     int64_t num_samples;
   };
   struct QpCounters {
     SampleCounter vp8;
   };
+  // |time_ms| should never decrease in consecutive calls to Add and MovingMax
+  // as if it's local time. Not thread-safe.
+  class MovingMaxCounter {
+   public:
+    explicit MovingMaxCounter(int window_length_ms) :
+      window_length_ms_(window_length_ms) {}
+    void Add(int sample, int64_t time_ms);
+    // Returns max sample in window given current time.
+    // Can be sped-up in case when MovingMax is called many times in a row
+    // without new elements added (not likely case currently) by removing
+    // obsolete elements from the beginning of the deque instead of skipping
+    // them. In that case deque should be marked as mutable.
+    rtc::Optional<int> MovingMax(int64_t time_ms) const;
+    void Reset();
+   private:
+    int window_length_ms_;
+    // Samples in the window are stored as pairs <time, sample> in this deque in
+    // chronological order. Samples what can't be maximum in any window are
+    // thrown out - deque always contain decreasing sequence of samples.
+    std::deque <std::pair<int64_t, int>> samples_;
+  };

[sprang_webrtc, 2017/08/18 09:06:49]

Interesting class. If no equivalent is available in rtc base, maybe you should
move it there and templetize it?
That would also make it easier to test this logic independently.

[ilnik, 2017/08/18 11:43:01]

Done.

 
   void UpdateHistograms() EXCLUSIVE_LOCKS_REQUIRED(crit_);
 
   void QualitySample() EXCLUSIVE_LOCKS_REQUIRED(crit_);
 
   // Removes info about old frames and then updates the framerate.
   void UpdateFramerate(int64_t now_ms) const EXCLUSIVE_LOCKS_REQUIRED(crit_);
 
   Clock* const clock_;
   // Ownership of this object lies with the owner of the ReceiveStatisticsProxy
@@ skipping 29 matching lines @@
   SampleCounter current_delay_counter_ GUARDED_BY(crit_);
   SampleCounter delay_counter_ GUARDED_BY(crit_);
   SampleCounter e2e_delay_counter_video_ GUARDED_BY(crit_);
   SampleCounter e2e_delay_counter_screenshare_ GUARDED_BY(crit_);
   SampleCounter interframe_delay_counter_video_ GUARDED_BY(crit_);
   SampleCounter interframe_delay_counter_screenshare_ GUARDED_BY(crit_);
   int64_t e2e_delay_max_ms_video_ GUARDED_BY(crit_);
   int64_t e2e_delay_max_ms_screenshare_ GUARDED_BY(crit_);
   int64_t interframe_delay_max_ms_video_  GUARDED_BY(crit_);
   int64_t interframe_delay_max_ms_screenshare_  GUARDED_BY(crit_);
+  MovingMaxCounter interframe_delay_max_moving_  GUARDED_BY(crit_);
   MaxCounter freq_offset_counter_ GUARDED_BY(crit_);
   int64_t first_report_block_time_ms_ GUARDED_BY(crit_);
   ReportBlockStats report_block_stats_ GUARDED_BY(crit_);
   QpCounters qp_counters_;  // Only accessed on the decoding thread.
   std::map<uint32_t, StreamDataCounters> rtx_stats_ GUARDED_BY(crit_);
   int64_t avg_rtt_ms_ GUARDED_BY(crit_);
   mutable std::map<int64_t, size_t> frame_window_ GUARDED_BY(&crit_);
   VideoContentType last_content_type_ GUARDED_BY(&crit_);
   rtc::Optional<int64_t> last_decoded_frame_time_ms_;
   rtc::Optional<TimingFrameInfo> timing_frame_info_ GUARDED_BY(&crit_);
 };
 
 }  // namespace webrtc
 #endif  // WEBRTC_VIDEO_RECEIVE_STATISTICS_PROXY_H_