PacketBuffer now can save how many times a packet has been nacked.

webrtc/modules/video_coding/packet_buffer.cc

 /*
  *  Copyright (c) 2016 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.
  */
 
@@ skipping 119 matching lines @@
 }
 
 void PacketBuffer::FindFrames(uint16_t seq_num) {
   size_t index = seq_num % size_;
   while (IsContinuous(seq_num)) {
     sequence_buffer_[index].continuous = true;
 
     // If all packets of the frame is continuous, find the first packet of the
     // frame and create an RtpFrameObject.
     if (sequence_buffer_[index].frame_end) {
-      int start_index = index;
+      size_t frame_size = 0;
+      int max_nack_count = -1;
       uint16_t start_seq_num = seq_num;
 
-      while (!sequence_buffer_[start_index].frame_begin) {
+      // Find the start index by searching backward until the packet with
+      // the |frame_begin| flag is set.
+      int start_index = index;
+      while (true) {
+        frame_size += data_buffer_[start_index].sizeBytes;
+        max_nack_count = std::max(
+            max_nack_count, data_buffer_[start_index].timesNacked);
         sequence_buffer_[start_index].frame_created = true;
+
+        if (sequence_buffer_[start_index].frame_begin)
+          break;
+
         start_index = start_index > 0 ? start_index - 1 : size_ - 1;
         start_seq_num--;
       }
-      sequence_buffer_[start_index].frame_created = true;
 
-      std::unique_ptr<RtpFrameObject> frame(
-          new RtpFrameObject(this, start_seq_num, seq_num));
+      std::unique_ptr<RtpFrameObject> frame(new RtpFrameObject(
+          this, start_seq_num, seq_num, frame_size, max_nack_count));
       reference_finder_.ManageFrame(std::move(frame));
     }
 
     index = (index + 1) % size_;
     ++seq_num;
   }
 }
 
 void PacketBuffer::ReturnFrame(RtpFrameObject* frame) {
   rtc::CritScope lock(&crit_);
@@ skipping 52 matching lines @@
 void PacketBuffer::Clear() {
   rtc::CritScope lock(&crit_);
   for (size_t i = 0; i < size_; ++i)
     sequence_buffer_[i].used = false;
 
   first_packet_received_ = false;
 }
 
 }  // namespace video_coding
 }  // namespace webrtc