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/*
* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef WEBRTC_MODULES_AUDIO_CODING_NETEQ_PACKET_H_
#define WEBRTC_MODULES_AUDIO_CODING_NETEQ_PACKET_H_
#include <list>
#include "webrtc/modules/include/module_common_types.h"
#include "webrtc/typedefs.h"
namespace webrtc {
// Struct for holding RTP packets.
struct Packet {
RTPHeader header;
uint8_t* payload; // Datagram excluding RTP header and header extension.
size_t payload_length;
bool primary; // Primary, i.e., not redundant payload.
int waiting_time;
bool sync_packet;
// Constructor.
Packet()
: payload(NULL),
payload_length(0),
primary(true),
waiting_time(0),
sync_packet(false) {
}
// Comparison operators. Establish a packet ordering based on (1) timestamp,
// (2) sequence number, (3) regular packet vs sync-packet and (4) redundancy.
// Timestamp and sequence numbers are compared taking wrap-around into
// account. If both timestamp and sequence numbers are identical and one of
// the packets is sync-packet, the regular packet is considered earlier. For
// two regular packets with the same sequence number and timestamp a primary
// payload is considered "smaller" than a secondary.
bool operator==(const Packet& rhs) const {
return (this->header.timestamp == rhs.header.timestamp &&
this->header.sequenceNumber == rhs.header.sequenceNumber &&
this->primary == rhs.primary &&
this->sync_packet == rhs.sync_packet);
}
bool operator!=(const Packet& rhs) const { return !operator==(rhs); }
bool operator<(const Packet& rhs) const {
if (this->header.timestamp == rhs.header.timestamp) {
if (this->header.sequenceNumber == rhs.header.sequenceNumber) {
// Timestamp and sequence numbers are identical. A sync packet should
// be recognized "larger" (i.e. "later") compared to a "network packet"
// (regular packet from network not sync-packet). If none of the packets
// are sync-packets, then deem the left hand side to be "smaller"
// (i.e., "earlier") if it is primary, and right hand side is not.
//
// The condition on sync packets to be larger than "network packets,"
// given same RTP sequence number and timestamp, guarantees that a
// "network packet" to be inserted in an earlier position into
// |packet_buffer_| compared to a sync packet of same timestamp and
// sequence number.
if (rhs.sync_packet)
return true;
if (this->sync_packet)
return false;
return (this->primary && !rhs.primary);
}
return (static_cast<uint16_t>(rhs.header.sequenceNumber
- this->header.sequenceNumber) < 0xFFFF / 2);
}
return (static_cast<uint32_t>(rhs.header.timestamp
- this->header.timestamp) < 0xFFFFFFFF / 2);
}
bool operator>(const Packet& rhs) const { return rhs.operator<(*this); }
bool operator<=(const Packet& rhs) const { return !operator>(rhs); }
bool operator>=(const Packet& rhs) const { return !operator<(rhs); }
};
// A list of packets.
typedef std::list<Packet*> PacketList;
} // namespace webrtc
#endif // WEBRTC_MODULES_AUDIO_CODING_NETEQ_PACKET_H_
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