AbsoluteSendTime rtp header extension publish MsTo24Bit conversion

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 19 matching lines @@
 //    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
 //   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 //   |  ID   | len=2 |              absolute send time               |
 //   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 const char* AbsoluteSendTime::kName =
     "http://www.webrtc.org/experiments/rtp-hdrext/abs-send-time";
 bool AbsoluteSendTime::IsSupportedFor(MediaType type) {
   return true;
 }
 
-bool AbsoluteSendTime::Parse(const uint8_t* data, uint32_t* value) {
-  *value = ByteReader<uint32_t, 3>::ReadBigEndian(data);
+bool AbsoluteSendTime::Parse(const uint8_t* data, uint32_t* time_24bits) {
+  *time_24bits = ByteReader<uint32_t, 3>::ReadBigEndian(data);
   return true;
 }
 
 bool AbsoluteSendTime::Write(uint8_t* data, int64_t time_ms) {
-  const uint32_t kAbsSendTimeFraction = 18;
-  uint32_t time_24_bits =
-      static_cast<uint32_t>(((time_ms << kAbsSendTimeFraction) + 500) / 1000) &
-      0x00FFFFFF;
-
-  ByteWriter<uint32_t, 3>::WriteBigEndian(data, time_24_bits);
+  ByteWriter<uint32_t, 3>::WriteBigEndian(data, MsTo24Bits(time_ms));
   return true;
 }
 
 // An RTP Header Extension for Client-to-Mixer Audio Level Indication
 //
 // https://datatracker.ietf.org/doc/draft-lennox-avt-rtp-audio-level-exthdr/
 //
 // The form of the audio level extension block:
 //
 //    0                   1
@@ skipping 132 matching lines @@
 bool VideoOrientation::Parse(const uint8_t* data, uint8_t* value) {
   *value = data[0];
   return true;
 }
 
 bool VideoOrientation::Write(uint8_t* data, uint8_t value) {
   data[0] = value;
   return true;
 }
 }  // namespace webrtc