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/*
* Copyright (c) 2014 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 "modules/audio_coding/neteq/tools/constant_pcm_packet_source.h"
#include <algorithm>
#include "modules/audio_coding/codecs/pcm16b/pcm16b.h"
#include "modules/audio_coding/neteq/tools/packet.h"
#include "rtc_base/checks.h"
namespace webrtc {
namespace test {
ConstantPcmPacketSource::ConstantPcmPacketSource(size_t payload_len_samples,
int16_t sample_value,
int sample_rate_hz,
int payload_type)
: payload_len_samples_(payload_len_samples),
packet_len_bytes_(2 * payload_len_samples_ + kHeaderLenBytes),
samples_per_ms_(sample_rate_hz / 1000),
next_arrival_time_ms_(0.0),
payload_type_(payload_type),
seq_number_(0),
timestamp_(0),
payload_ssrc_(0xABCD1234) {
size_t encoded_len = WebRtcPcm16b_Encode(&sample_value, 1, encoded_sample_);
RTC_CHECK_EQ(2U, encoded_len);
}
std::unique_ptr<Packet> ConstantPcmPacketSource::NextPacket() {
RTC_CHECK_GT(packet_len_bytes_, kHeaderLenBytes);
rtc::CopyOnWriteBuffer packet_buffer(packet_len_bytes_);
uint8_t* packet_memory = packet_buffer.MutableData();
// Fill the payload part of the packet memory with the pre-encoded value.
for (unsigned i = 0; i < 2 * payload_len_samples_; ++i)
packet_memory[kHeaderLenBytes + i] = encoded_sample_[i % 2];
WriteHeader(packet_memory);
// `packet` assumes ownership of `packet_memory`.
auto packet =
std::make_unique<Packet>(std::move(packet_buffer), next_arrival_time_ms_);
next_arrival_time_ms_ += payload_len_samples_ / samples_per_ms_;
return packet;
}
void ConstantPcmPacketSource::WriteHeader(uint8_t* packet_memory) {
packet_memory[0] = 0x80;
packet_memory[1] = static_cast<uint8_t>(payload_type_);
packet_memory[2] = seq_number_ >> 8;
packet_memory[3] = seq_number_ & 0xFF;
packet_memory[4] = timestamp_ >> 24;
packet_memory[5] = (timestamp_ >> 16) & 0xFF;
packet_memory[6] = (timestamp_ >> 8) & 0xFF;
packet_memory[7] = timestamp_ & 0xFF;
packet_memory[8] = payload_ssrc_ >> 24;
packet_memory[9] = (payload_ssrc_ >> 16) & 0xFF;
packet_memory[10] = (payload_ssrc_ >> 8) & 0xFF;
packet_memory[11] = payload_ssrc_ & 0xFF;
++seq_number_;
timestamp_ += static_cast<uint32_t>(payload_len_samples_);
}
} // namespace test
} // namespace webrtc