media/cast/congestion_control/congestion_control.h

   1 // Copyright 2013 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_CONGESTION_CONTROL_CONGESTION_CONTROL_H_
   6 #define MEDIA_CAST_CONGESTION_CONTROL_CONGESTION_CONTROL_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/memory/scoped_ptr.h"
  10 #include "base/time/tick_clock.h"
  11 #include "base/time/time.h"
  12
  13 namespace media {
  14 namespace cast {
  15
  16 class CongestionControl {
  17  public:
  18   CongestionControl(base::TickClock* clock,
  19                     float congestion_control_back_off,
  20                     uint32 max_bitrate_configured,
  21                     uint32 min_bitrate_configured,
  22                     uint32 start_bitrate);
  23
  24   virtual ~CongestionControl();
  25
  26   // Don't call OnAck if the same message contain a NACK.
  27   // Returns true if the bitrate have changed.
  28   bool OnAck(base::TimeDelta rtt_ms, uint32* new_bitrate);
  29
  30   // Returns true if the bitrate have changed.
  31   bool OnNack(base::TimeDelta rtt_ms, uint32* new_bitrate);
  32
  33
  34  private:
  35   base::TickClock* const clock_;  // Not owned by this class.
  36   const float congestion_control_back_off_;
  37   const uint32 max_bitrate_configured_;
  38   const uint32 min_bitrate_configured_;
  39   uint32 bitrate_;
  40   base::TimeTicks time_last_increase_;
  41   base::TimeTicks time_last_decrease_;
  42
  43   DISALLOW_COPY_AND_ASSIGN(CongestionControl);
  44 };
  45
  46 }  // namespace cast
  47 }  // namespace media
  48
  49 #endif  // MEDIA_CAST_CONGESTION_CONTROL_CONGESTION_CONTROL_H_