media/cast/rtp_timestamp_helper.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef MEDIA_CAST_RTP_TIMESTAMP_HELPER_H_
   6 #define MEDIA_CAST_RTP_TIMESTAMP_HELPER_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/time/time.h"
  10
  11 namespace media {
  12 namespace cast {
  13
  14 // A helper class used to convert current time ticks into RTP timestamp.
  15 class RtpTimestampHelper {
  16  public:
  17   explicit RtpTimestampHelper(int frequency);
  18   ~RtpTimestampHelper();
  19
  20   // Compute a RTP timestamp using current time, last encoded time and
  21   // last encoded RTP timestamp.
  22   // Return true if |rtp_timestamp| is computed.
  23   bool GetCurrentTimeAsRtpTimestamp(const base::TimeTicks& now,
  24                                     uint32* rtp_timestamp) const;
  25
  26   // Store the capture time and the corresponding RTP timestamp for the
  27   // last encoded frame.
  28   void StoreLatestTime(base::TimeTicks capture_time, uint32 rtp_timestamp);
  29
  30  private:
  31   int frequency_;
  32   base::TimeTicks last_capture_time_;
  33   uint32 last_rtp_timestamp_;
  34
  35   DISALLOW_COPY_AND_ASSIGN(RtpTimestampHelper);
  36 };
  37
  38 }  // namespace cast
  39 }  // namespace media
  40
  41 #endif  // MEDIA_CAST_CAST_DEFINES_H_