Implement timing frames.

webrtc/modules/rtp_rtcp/source/rtp_header_extensions.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 226 matching lines @@
   }
   return false;
 }
 
 bool VideoContentTypeExtension::Write(uint8_t* data,
                                       VideoContentType content_type) {
   data[0] = static_cast<uint8_t>(content_type);
   return true;
 }
 
+// Video Timing.
+// 5 timestamps in milliseconds counted from capture time stored in rtp header:
+// ecode start/finish, packetization complete, pacer exit and reserved for
+// modification by the network modification.
+//    0                   1                   2                   3
+//    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2
+//   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+//   |  ID   | len=9 |  encode start ms delta          | encode finish |
+//   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+//   | ms delta      |  packetizer finish ms delta     |   pacer exit  |
+//   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+//   | ms delta      |  network timestamp ms delta     |               |
+//   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+

[sprang_webrtc, 2017/05/31 11:12:55]

So the empty 8bit block at the end is not a part of this block, right? Or is it
just reserved and unused?

[ilnik, 2017/05/31 15:17:45]

Not part of the extension.

+constexpr RTPExtensionType VideoTimingExtension::kId;
+constexpr uint8_t VideoTimingExtension::kValueSizeBytes;
+constexpr const char* VideoTimingExtension::kUri;
+
+bool VideoTimingExtension::Parse(rtc::ArrayView<const uint8_t> data,
+                                 VideoTiming* timing) {
+  RTC_DCHECK(timing);
+  if (data.size() != 10)
+    return false;
+  timing->encode_start_ms_delta =
+      ByteReader<uint16_t, 2>::ReadBigEndian(data.data());

[sprang_webrtc, 2017/05/31 11:12:55]

You don't need the second template parameter here. It's only used if the number
of bytes to read is less than the size of the type being read, typically reading
24bit values into a 32bit int type.

[ilnik, 2017/05/31 15:17:45]

Done.

+  timing->encode_finish_ms_delta = ByteReader<uint16_t, 2>::ReadBigEndian(
+      data.data() + 2 * VideoTiming::kEncodeFinishIdx);
+  timing->packetization_finish_ms_delta =
+      ByteReader<uint16_t, 2>::ReadBigEndian(
+          data.data() + 2 * VideoTiming::kPacketizationFinishDeltaIdx);
+  timing->pacer_exit_ms_delta = ByteReader<uint16_t, 2>::ReadBigEndian(
+      data.data() + 2 * VideoTiming::kPacerExitDeltaIdx);
+  timing->network_timstamp_ms_delta = ByteReader<uint16_t, 2>::ReadBigEndian(
+      data.data() + 2 * VideoTiming::kNetworkTimestampDeltaIdx);
+  timing->is_timing_frame = true;
+  return true;
+}
+
+bool VideoTimingExtension::Write(uint8_t* data, const VideoTiming& timing) {
+  ByteWriter<uint16_t, 2>::WriteBigEndian(data, timing.encode_start_ms_delta);
+  ByteWriter<uint16_t, 2>::WriteBigEndian(
+      data + 2 * VideoTiming::kEncodeFinishIdx, timing.encode_finish_ms_delta);
+  ByteWriter<uint16_t, 2>::WriteBigEndian(
+      data + 2 * VideoTiming::kPacketizationFinishDeltaIdx,
+      timing.packetization_finish_ms_delta);
+  ByteWriter<uint16_t, 2>::WriteBigEndian(
+      data + 2 * VideoTiming::kPacerExitDeltaIdx, timing.pacer_exit_ms_delta);
+  ByteWriter<uint16_t, 2>::WriteBigEndian(
+      data + 2 * VideoTiming::kNetworkTimestampDeltaIdx, 0);  // reserved
+  return true;
+}
+
+bool VideoTimingExtension::Write(uint8_t* data,
+                                 uint16_t time_delta_ms,
+                                 uint8_t idx) {
+  ByteWriter<uint16_t, 2>::WriteBigEndian(data + 2 * idx, time_delta_ms);
+  return true;
+}
+
 // RtpStreamId.
 constexpr RTPExtensionType RtpStreamId::kId;
 constexpr const char* RtpStreamId::kUri;
 
 bool RtpStreamId::Parse(rtc::ArrayView<const uint8_t> data, StreamId* rsid) {
   if (data.empty() || data[0] == 0)  // Valid rsid can't be empty.
     return false;
   rsid->Set(data);
   RTC_DCHECK(!rsid->empty());
   return true;
@@ skipping 49 matching lines @@
 
 size_t RepairedRtpStreamId::ValueSize(const std::string& rsid) {
   return RtpStreamId::ValueSize(rsid);
 }
 
 bool RepairedRtpStreamId::Write(uint8_t* data, const std::string& rsid) {
   return RtpStreamId::Write(data, rsid);
 }
 
 }  // namespace webrtc