media/cast/net/rtp/frame_buffer.cc

   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 #include "media/cast/net/rtp/frame_buffer.h"
   6
   7 #include "base/logging.h"
   8
   9 namespace media {
  10 namespace cast {
  11
  12 FrameBuffer::FrameBuffer()
  13     : frame_id_(0),
  14       max_packet_id_(0),
  15       num_packets_received_(0),
  16       max_seen_packet_id_(0),
  17       new_playout_delay_ms_(0),
  18       is_key_frame_(false),
  19       total_data_size_(0),
  20       last_referenced_frame_id_(0),
  21       packets_() {}
  22
  23 FrameBuffer::~FrameBuffer() {}
  24
  25 bool FrameBuffer::InsertPacket(const uint8* payload_data,
  26                                size_t payload_size,
  27                                const RtpCastHeader& rtp_header) {
  28   // Is this the first packet in the frame?
  29   if (packets_.empty()) {
  30     frame_id_ = rtp_header.frame_id;
  31     max_packet_id_ = rtp_header.max_packet_id;
  32     is_key_frame_ = rtp_header.is_key_frame;
  33     new_playout_delay_ms_ = rtp_header.new_playout_delay_ms;
  34     if (is_key_frame_)
  35       DCHECK_EQ(rtp_header.frame_id, rtp_header.reference_frame_id);
  36     last_referenced_frame_id_ = rtp_header.reference_frame_id;
  37     rtp_timestamp_ = rtp_header.rtp_timestamp;
  38   }
  39   // Is this the correct frame?
  40   if (rtp_header.frame_id != frame_id_)
  41     return false;
  42
  43   // Insert every packet only once.
  44   if (packets_.find(rtp_header.packet_id) != packets_.end()) {
  45     return false;
  46   }
  47
  48   std::vector<uint8> data;
  49   std::pair<PacketMap::iterator, bool> retval =
  50       packets_.insert(make_pair(rtp_header.packet_id, data));
  51
  52   // Insert the packet.
  53   retval.first->second.resize(payload_size);
  54   std::copy(
  55       payload_data, payload_data + payload_size, retval.first->second.begin());
  56
  57   ++num_packets_received_;
  58   max_seen_packet_id_ = std::max(max_seen_packet_id_, rtp_header.packet_id);
  59   total_data_size_ += payload_size;
  60   return true;
  61 }
  62
  63 bool FrameBuffer::Complete() const {
  64   return num_packets_received_ - 1 == max_packet_id_;
  65 }
  66
  67 bool FrameBuffer::AssembleEncodedFrame(EncodedFrame* frame) const {
  68   if (!Complete())
  69     return false;
  70
  71   // Frame is complete -> construct.
  72   if (is_key_frame_)
  73     frame->dependency = EncodedFrame::KEY;
  74   else if (frame_id_ == last_referenced_frame_id_)
  75     frame->dependency = EncodedFrame::INDEPENDENT;
  76   else
  77     frame->dependency = EncodedFrame::DEPENDENT;
  78   frame->frame_id = frame_id_;
  79   frame->referenced_frame_id = last_referenced_frame_id_;
  80   frame->rtp_timestamp = rtp_timestamp_;
  81   frame->new_playout_delay_ms = new_playout_delay_ms_;
  82
  83   // Build the data vector.
  84   frame->data.clear();
  85   frame->data.reserve(total_data_size_);
  86   PacketMap::const_iterator it;
  87   for (it = packets_.begin(); it != packets_.end(); ++it)
  88     frame->data.insert(frame->data.end(), it->second.begin(), it->second.end());
  89   return true;
  90 }
  91
  92 void FrameBuffer::GetMissingPackets(bool newest_frame,
  93                                     PacketIdSet* missing_packets) const {
  94   // Missing packets capped by max_seen_packet_id_.
  95   // (Iff it's the latest frame)
  96   int maximum = newest_frame ? max_seen_packet_id_ : max_packet_id_;
  97   int packet = 0;
  98   for (PacketMap::const_iterator i = packets_.begin();
  99        i != packets_.end() && packet <= maximum;
 100        ++i) {
 101     int end = std::min<int>(i->first, maximum + 1);
 102     while (packet < end) {
 103       missing_packets->insert(packet);
 104       packet++;
 105     }
 106     packet++;
 107   }
 108   while (packet <= maximum) {
 109     missing_packets->insert(packet);
 110     packet++;
 111   }
 112 }
 113
 114
 115 }  // namespace cast
 116 }  // namespace media