Line data    Source code

       1             : /*
       2             :  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
       3             :  *
       4             :  *  Use of this source code is governed by a BSD-style license
       5             :  *  that can be found in the LICENSE file in the root of the source
       6             :  *  tree. An additional intellectual property rights grant can be found
       7             :  *  in the file PATENTS.  All contributing project authors may
       8             :  *  be found in the AUTHORS file in the root of the source tree.
       9             :  */
      10             : 
      11             : #ifndef WEBRTC_MODULES_AUDIO_CODING_NETEQ_PACKET_H_
      12             : #define WEBRTC_MODULES_AUDIO_CODING_NETEQ_PACKET_H_
      13             : 
      14             : #include <list>
      15             : #include <memory>
      16             : 
      17             : #include "webrtc/base/buffer.h"
      18             : #include "webrtc/modules/audio_coding/codecs/audio_decoder.h"
      19             : #include "webrtc/modules/audio_coding/neteq/tick_timer.h"
      20             : #include "webrtc/typedefs.h"
      21             : 
      22             : namespace webrtc {
      23             : 
      24             : // Struct for holding RTP packets.
      25           0 : struct Packet {
      26             :   struct Priority {
      27           0 :     Priority() : codec_level(0), red_level(0) {}
      28           0 :     Priority(int codec_level, int red_level)
      29           0 :         : codec_level(codec_level), red_level(red_level) {
      30           0 :       CheckInvariant();
      31           0 :     }
      32             : 
      33             :     int codec_level;
      34             :     int red_level;
      35             : 
      36             :     // Priorities are sorted low-to-high, first on the level the codec
      37             :     // prioritizes it, then on the level of RED packet it is; i.e. if it is a
      38             :     // primary or secondary payload of a RED packet. For example: with Opus, an
      39             :     // Fec packet (which the decoder prioritizes lower than a regular packet)
      40             :     // will not be used if there is _any_ RED payload for the same
      41             :     // timeframe. The highest priority packet will have levels {0, 0}. Negative
      42             :     // priorities are not allowed.
      43           0 :     bool operator<(const Priority& b) const {
      44           0 :       CheckInvariant();
      45           0 :       b.CheckInvariant();
      46           0 :       if (codec_level == b.codec_level)
      47           0 :         return red_level < b.red_level;
      48             : 
      49           0 :       return codec_level < b.codec_level;
      50             :     }
      51           0 :     bool operator==(const Priority& b) const {
      52           0 :       CheckInvariant();
      53           0 :       b.CheckInvariant();
      54           0 :       return codec_level == b.codec_level && red_level == b.red_level;
      55             :     }
      56           0 :     bool operator!=(const Priority& b) const { return !(*this == b); }
      57             :     bool operator>(const Priority& b) const { return b < *this; }
      58             :     bool operator<=(const Priority& b) const { return !(b > *this); }
      59             :     bool operator>=(const Priority& b) const { return !(b < *this); }
      60             : 
      61             :    private:
      62           0 :     void CheckInvariant() const {
      63           0 :       RTC_DCHECK_GE(codec_level, 0);
      64           0 :       RTC_DCHECK_GE(red_level, 0);
      65           0 :     }
      66             :   };
      67             : 
      68             :   uint32_t timestamp;
      69             :   uint16_t sequence_number;
      70             :   uint8_t payload_type;
      71             :   // Datagram excluding RTP header and header extension.
      72             :   rtc::Buffer payload;
      73             :   Priority priority;
      74             :   std::unique_ptr<TickTimer::Stopwatch> waiting_time;
      75             :   std::unique_ptr<AudioDecoder::EncodedAudioFrame> frame;
      76             : 
      77             :   Packet();
      78             :   Packet(Packet&& b);
      79             :   ~Packet();
      80             : 
      81             :   // Packets should generally be moved around but sometimes it's useful to make
      82             :   // a copy, for example for testing purposes. NOTE: Will only work for
      83             :   // un-parsed packets, i.e. |frame| must be unset. The payload will, however,
      84             :   // be copied. |waiting_time| will also not be copied.
      85             :   Packet Clone() const;
      86             : 
      87             :   Packet& operator=(Packet&& b);
      88             : 
      89             :   // Comparison operators. Establish a packet ordering based on (1) timestamp,
      90             :   // (2) sequence number and (3) redundancy.
      91             :   // Timestamp and sequence numbers are compared taking wrap-around into
      92             :   // account. For two packets with the same sequence number and timestamp a
      93             :   // primary payload is considered "smaller" than a secondary.
      94             :   bool operator==(const Packet& rhs) const {
      95             :     return (this->timestamp == rhs.timestamp &&
      96             :             this->sequence_number == rhs.sequence_number &&
      97             :             this->priority == rhs.priority);
      98             :   }
      99             :   bool operator!=(const Packet& rhs) const { return !operator==(rhs); }
     100           0 :   bool operator<(const Packet& rhs) const {
     101           0 :     if (this->timestamp == rhs.timestamp) {
     102           0 :       if (this->sequence_number == rhs.sequence_number) {
     103             :         // Timestamp and sequence numbers are identical - deem the left hand
     104             :         // side to be "smaller" (i.e., "earlier") if it has higher priority.
     105           0 :         return this->priority < rhs.priority;
     106             :       }
     107           0 :       return (static_cast<uint16_t>(rhs.sequence_number -
     108           0 :                                     this->sequence_number) < 0xFFFF / 2);
     109             :     }
     110           0 :     return (static_cast<uint32_t>(rhs.timestamp - this->timestamp) <
     111           0 :             0xFFFFFFFF / 2);
     112             :   }
     113             :   bool operator>(const Packet& rhs) const { return rhs.operator<(*this); }
     114             :   bool operator<=(const Packet& rhs) const { return !operator>(rhs); }
     115           0 :   bool operator>=(const Packet& rhs) const { return !operator<(rhs); }
     116             : 
     117           0 :   bool empty() const { return !frame && payload.empty(); }
     118             : };
     119             : 
     120             : // A list of packets.
     121             : typedef std::list<Packet> PacketList;
     122             : 
     123             : }  // namespace webrtc
     124             : #endif  // WEBRTC_MODULES_AUDIO_CODING_NETEQ_PACKET_H_