Implement timing frames.

webrtc/modules/rtp_rtcp/source/rtp_header_extensions.cc

Index: webrtc/modules/rtp_rtcp/source/rtp_header_extensions.cc
diff --git a/webrtc/modules/rtp_rtcp/source/rtp_header_extensions.cc b/webrtc/modules/rtp_rtcp/source/rtp_header_extensions.cc
index 3bb9bc5553849a9acf1d756fd489b9d94c6f1ad3..f8041701ceabb200f226ce36456d55a51a2b1a9f 100644
--- a/webrtc/modules/rtp_rtcp/source/rtp_header_extensions.cc
+++ b/webrtc/modules/rtp_rtcp/source/rtp_header_extensions.cc
@@ -244,6 +244,65 @@ bool VideoContentTypeExtension::Write(uint8_t* data,
   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;