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/*
* Copyright (c) 2016 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 MODULES_RTP_RTCP_INCLUDE_FLEXFEC_SENDER_H_
#define MODULES_RTP_RTCP_INCLUDE_FLEXFEC_SENDER_H_
#include <memory>
#include <string>
#include <vector>
#include "absl/strings/string_view.h"
#include "api/array_view.h"
#include "api/rtp_parameters.h"
#include "api/units/timestamp.h"
#include "modules/rtp_rtcp/include/rtp_header_extension_map.h"
#include "modules/rtp_rtcp/include/rtp_rtcp_defines.h"
#include "modules/rtp_rtcp/source/rtp_header_extension_size.h"
#include "modules/rtp_rtcp/source/ulpfec_generator.h"
#include "modules/rtp_rtcp/source/video_fec_generator.h"
#include "rtc_base/bitrate_tracker.h"
#include "rtc_base/random.h"
#include "rtc_base/synchronization/mutex.h"
namespace webrtc {
class Clock;
class RtpPacketToSend;
// Note that this class is not thread safe, and thus requires external
// synchronization. Currently, this is done using the lock in PayloadRouter.
class FlexfecSender : public VideoFecGenerator {
public:
FlexfecSender(int payload_type,
uint32_t ssrc,
uint32_t protected_media_ssrc,
absl::string_view mid,
const std::vector<RtpExtension>& rtp_header_extensions,
rtc::ArrayView<const RtpExtensionSize> extension_sizes,
const RtpState* rtp_state,
Clock* clock);
~FlexfecSender();
FecType GetFecType() const override {
return VideoFecGenerator::FecType::kFlexFec;
}
absl::optional<uint32_t> FecSsrc() override { return ssrc_; }
// Sets the FEC rate, max frames sent before FEC packets are sent,
// and what type of generator matrices are used.
void SetProtectionParameters(const FecProtectionParams& delta_params,
const FecProtectionParams& key_params) override;
// 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 GetFecPackets().
void AddPacketAndGenerateFec(const RtpPacketToSend& packet) override;
// Returns generated FlexFEC packets.
std::vector<std::unique_ptr<RtpPacketToSend>> GetFecPackets() override;
// Returns the overhead, per packet, for FlexFEC.
size_t MaxPacketOverhead() const override;
DataRate CurrentFecRate() const override;
// Only called on the VideoSendStream queue, after operation has shut down.
absl::optional<RtpState> GetRtpState() override;
private:
// Utility.
Clock* const clock_;
Random random_;
Timestamp last_generated_packet_ = Timestamp::MinusInfinity();
// Config.
const int payload_type_;
const uint32_t timestamp_offset_;
const uint32_t ssrc_;
const uint32_t protected_media_ssrc_;
// MID value to send in the MID header extension.
const std::string mid_;
// Sequence number of next packet to generate.
uint16_t seq_num_;
// Implementation.
UlpfecGenerator ulpfec_generator_;
const RtpHeaderExtensionMap rtp_header_extension_map_;
const size_t header_extensions_size_;
mutable Mutex mutex_;
BitrateTracker fec_bitrate_ RTC_GUARDED_BY(mutex_);
};
} // namespace webrtc
#endif // MODULES_RTP_RTCP_INCLUDE_FLEXFEC_SENDER_H_
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