media/cast/framer/framer.cc

   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 #include "media/cast/framer/framer.h"
   6
   7 #include "base/logging.h"
   8
   9 namespace media {
  10 namespace cast {
  11
  12 typedef FrameList::const_iterator ConstFrameIterator;
  13
  14 Framer::Framer(base::TickClock* clock,
  15                RtpPayloadFeedback* incoming_payload_feedback,
  16                uint32 ssrc,
  17                bool decoder_faster_than_max_frame_rate,
  18                int max_unacked_frames)
  19     : decoder_faster_than_max_frame_rate_(decoder_faster_than_max_frame_rate),
  20       cast_msg_builder_(
  21           new CastMessageBuilder(clock,
  22                                  incoming_payload_feedback,
  23                                  &frame_id_map_,
  24                                  ssrc,
  25                                  decoder_faster_than_max_frame_rate,
  26                                  max_unacked_frames)) {
  27   DCHECK(incoming_payload_feedback) << "Invalid argument";
  28 }
  29
  30 Framer::~Framer() {}
  31
  32 bool Framer::InsertPacket(const uint8* payload_data,
  33                           size_t payload_size,
  34                           const RtpCastHeader& rtp_header,
  35                           bool* duplicate) {
  36   *duplicate = false;
  37   PacketType packet_type = frame_id_map_.InsertPacket(rtp_header);
  38   if (packet_type == kTooOldPacket) {
  39     return false;
  40   }
  41   if (packet_type == kDuplicatePacket) {
  42     VLOG(3) << "Packet already received, ignored: frame "
  43             << static_cast<int>(rtp_header.frame_id) << ", packet "
  44             << rtp_header.packet_id;
  45     *duplicate = true;
  46     return false;
  47   }
  48
  49   // Does this packet belong to a new frame?
  50   FrameList::iterator it = frames_.find(rtp_header.frame_id);
  51   if (it == frames_.end()) {
  52     // New frame.
  53     linked_ptr<FrameBuffer> frame_buffer(new FrameBuffer());
  54     frame_buffer->InsertPacket(payload_data, payload_size, rtp_header);
  55     frames_.insert(std::make_pair(rtp_header.frame_id, frame_buffer));
  56   } else {
  57     // Insert packet to existing frame buffer.
  58     it->second->InsertPacket(payload_data, payload_size, rtp_header);
  59   }
  60
  61   return packet_type == kNewPacketCompletingFrame;
  62 }
  63
  64 // This does not release the frame.
  65 bool Framer::GetEncodedFrame(transport::EncodedFrame* frame,
  66                              bool* next_frame,
  67                              bool* have_multiple_decodable_frames) {
  68   *have_multiple_decodable_frames = frame_id_map_.HaveMultipleDecodableFrames();
  69
  70   uint32 frame_id;
  71   // Find frame id.
  72   if (frame_id_map_.NextContinuousFrame(&frame_id)) {
  73     // We have our next frame.
  74     *next_frame = true;
  75   } else {
  76     // Check if we can skip frames when our decoder is too slow.
  77     if (!decoder_faster_than_max_frame_rate_)
  78       return false;
  79
  80     if (!frame_id_map_.NextFrameAllowingSkippingFrames(&frame_id)) {
  81       return false;
  82     }
  83     *next_frame = false;
  84   }
  85
  86   if (*next_frame) {
  87     VLOG(2) << "ACK frame " << frame_id;
  88     cast_msg_builder_->CompleteFrameReceived(frame_id);
  89   }
  90
  91   ConstFrameIterator it = frames_.find(frame_id);
  92   DCHECK(it != frames_.end());
  93   if (it == frames_.end())
  94     return false;
  95
  96   return it->second->AssembleEncodedFrame(frame);
  97 }
  98
  99 void Framer::Reset() {
 100   frame_id_map_.Clear();
 101   frames_.clear();
 102   cast_msg_builder_->Reset();
 103 }
 104
 105 void Framer::ReleaseFrame(uint32 frame_id) {
 106   frame_id_map_.RemoveOldFrames(frame_id);
 107   frames_.erase(frame_id);
 108
 109   // We have a frame - remove all frames with lower frame id.
 110   bool skipped_old_frame = false;
 111   FrameList::iterator it;
 112   for (it = frames_.begin(); it != frames_.end();) {
 113     if (IsOlderFrameId(it->first, frame_id)) {
 114       frames_.erase(it++);
 115       skipped_old_frame = true;
 116     } else {
 117       ++it;
 118     }
 119   }
 120   if (skipped_old_frame) {
 121     cast_msg_builder_->UpdateCastMessage();
 122   }
 123 }
 124
 125 bool Framer::TimeToSendNextCastMessage(base::TimeTicks* time_to_send) {
 126   return cast_msg_builder_->TimeToSendNextCastMessage(time_to_send);
 127 }
 128
 129 void Framer::SendCastMessage() { cast_msg_builder_->UpdateCastMessage(); }
 130
 131 }  // namespace cast
 132 }  // namespace media