blob: 52e03cdad99168b6922dd0cb487ed0080a8cf25c [file] [log] [blame]
* 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.
#include <list>
#include <memory>
#include <vector>
#include "webrtc/modules/rtp_rtcp/source/forward_error_correction.h"
namespace webrtc {
class FlexfecSender;
class RedPacket {
explicit RedPacket(size_t length);
void CreateHeader(const uint8_t* rtp_header,
size_t header_length,
int red_payload_type,
int payload_type);
void SetSeqNum(int seq_num);
void AssignPayload(const uint8_t* payload, size_t length);
void ClearMarkerBit();
uint8_t* data() const;
size_t length() const;
std::unique_ptr<uint8_t[]> data_;
size_t length_;
size_t header_length_;
class UlpfecGenerator {
friend class FlexfecSender;
static std::unique_ptr<RedPacket> BuildRedPacket(const uint8_t* data_buffer,
size_t payload_length,
size_t rtp_header_length,
int red_payload_type);
void SetFecParameters(const FecProtectionParams& params);
// Adds a media packet to the internal buffer. When enough media packets
// have been added, the FEC packets are generated and stored internally.
// These FEC packets are then obtained by calling GetFecPacketsAsRed().
int AddRtpPacketAndGenerateFec(const uint8_t* data_buffer,
size_t payload_length,
size_t rtp_header_length);
// Returns true if there are generated FEC packets available.
bool FecAvailable() const;
size_t NumAvailableFecPackets() const;
// Returns the overhead, per packet, for FEC (and possibly RED).
size_t MaxPacketOverhead() const;
// Returns generated FEC packets with RED headers added.
std::vector<std::unique_ptr<RedPacket>> GetUlpfecPacketsAsRed(
int red_payload_type,
int ulpfec_payload_type,
uint16_t first_seq_num,
size_t rtp_header_length);
explicit UlpfecGenerator(std::unique_ptr<ForwardErrorCorrection> fec);
// Overhead is defined as relative to the number of media packets, and not
// relative to total number of packets. This definition is inherited from the
// protection factor produced by video_coding module and how the FEC
// generation is implemented.
int Overhead() const;
// Returns true if the excess overhead (actual - target) for the FEC is below
// the amount |kMaxExcessOverhead|. This effects the lower protection level
// cases and low number of media packets/frame. The target overhead is given
// by |params_.fec_rate|, and is only achievable in the limit of large number
// of media packets.
bool ExcessOverheadBelowMax() const;
// Returns true if the number of added media packets is at least
// |min_num_media_packets_|. This condition tries to capture the effect
// that, for the same amount of protection/overhead, longer codes
// (e.g. (2k,2m) vs (k,m)) are generally more effective at recovering losses.
bool MinimumMediaPacketsReached() const;
void ResetState();
std::unique_ptr<ForwardErrorCorrection> fec_;
ForwardErrorCorrection::PacketList media_packets_;
std::list<ForwardErrorCorrection::Packet*> generated_fec_packets_;
int num_protected_frames_;
int min_num_media_packets_;
FecProtectionParams params_;
FecProtectionParams new_params_;
} // namespace webrtc