ZLMediaKit/src/Extension/AACRtp.cpp
2020-05-11 23:25:12 +08:00

137 lines
4.2 KiB
C++
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/*
* Copyright (c) 2016 The ZLMediaKit project authors. All Rights Reserved.
*
* This file is part of ZLMediaKit(https://github.com/xiongziliang/ZLMediaKit).
*
* Use of this source code is governed by MIT license that can be found in the
* LICENSE file in the root of the source tree. All contributing project authors
* may be found in the AUTHORS file in the root of the source tree.
*/
#include "AACRtp.h"
#define AAC_MAX_FRAME_SIZE (2 * 1024)
namespace mediakit{
AACRtpEncoder::AACRtpEncoder(uint32_t ui32Ssrc,
uint32_t ui32MtuSize,
uint32_t ui32SampleRate,
uint8_t ui8PlayloadType,
uint8_t ui8Interleaved) :
RtpInfo(ui32Ssrc,
ui32MtuSize,
ui32SampleRate,
ui8PlayloadType,
ui8Interleaved){
}
void AACRtpEncoder::inputFrame(const Frame::Ptr &frame) {
GET_CONFIG(uint32_t, cycleMS, Rtp::kCycleMS);
auto uiStamp = frame->dts();
auto pcData = frame->data() + frame->prefixSize();
auto iLen = frame->size() - frame->prefixSize();
uiStamp %= cycleMS;
char *ptr = (char *) pcData;
int iSize = iLen;
while (iSize > 0) {
if (iSize <= _ui32MtuSize - 20) {
_aucSectionBuf[0] = 0;
_aucSectionBuf[1] = 16;
_aucSectionBuf[2] = iLen >> 5;
_aucSectionBuf[3] = (iLen & 0x1F) << 3;
memcpy(_aucSectionBuf + 4, ptr, iSize);
makeAACRtp(_aucSectionBuf, iSize + 4, true, uiStamp);
break;
}
_aucSectionBuf[0] = 0;
_aucSectionBuf[1] = 16;
_aucSectionBuf[2] = (iLen) >> 5;
_aucSectionBuf[3] = (iLen & 0x1F) << 3;
memcpy(_aucSectionBuf + 4, ptr, _ui32MtuSize - 20);
makeAACRtp(_aucSectionBuf, _ui32MtuSize - 16, false, uiStamp);
ptr += (_ui32MtuSize - 20);
iSize -= (_ui32MtuSize - 20);
}
}
void AACRtpEncoder::makeAACRtp(const void *data, unsigned int len, bool mark, uint32_t uiStamp) {
RtpCodec::inputRtp(makeRtp(getTrackType(),data,len,mark,uiStamp), false);
}
/////////////////////////////////////////////////////////////////////////////////////
AACRtpDecoder::AACRtpDecoder(const Track::Ptr &track){
auto aacTrack = dynamic_pointer_cast<AACTrack>(track);
if(!aacTrack || !aacTrack->ready()){
WarnL << "该aac track无效!";
}else{
_aac_cfg = aacTrack->getAacCfg();
}
_adts = obtainFrame();
}
AACRtpDecoder::AACRtpDecoder() {
_adts = obtainFrame();
}
AACFrame::Ptr AACRtpDecoder::obtainFrame() {
//从缓存池重新申请对象,防止覆盖已经写入环形缓存的对象
auto frame = ResourcePoolHelper<AACFrame>::obtainObj();
frame->_prefix_size = ADTS_HEADER_LEN;
//预留7个字节的空位以便后续覆盖
frame->_buffer.assign(ADTS_HEADER_LEN,(char)0);
return frame;
}
bool AACRtpDecoder::inputRtp(const RtpPacket::Ptr &rtppack, bool key_pos) {
//rtp数据开始部分
uint8_t *ptr = (uint8_t *) rtppack->data() + rtppack->offset;
//rtp数据末尾
const uint8_t *end = (uint8_t *) rtppack->data() + rtppack->size();
//首2字节表示Au-Header的个数单位bit所以除以16得到Au-Header个数
const uint16_t au_header_count = ((ptr[0] << 8) | ptr[1]) >> 4;
//忽略Au-Header区
ptr += 2 + au_header_count * 2;
static const uint32_t max_size = AAC_MAX_FRAME_SIZE - ADTS_HEADER_LEN;
while (ptr < end) {
auto size = (uint32_t) (end - ptr);
if(size > max_size){
size = max_size;
}
if (_adts->size() + size > AAC_MAX_FRAME_SIZE) {
//数据太多了,先清空
flushData();
}
//追加aac数据
_adts->_buffer.append((char *)ptr, size);
_adts->_dts = rtppack->timeStamp;
ptr += size;
}
if (rtppack->mark) {
//最后一个rtp分片
flushData();
}
return false;
}
void AACRtpDecoder::flushData() {
if (_adts->size() == ADTS_HEADER_LEN) {
//没有有效数据
return;
}
//覆盖adts头
dumpAacConfig(_aac_cfg, _adts->size(), (uint8_t *) _adts->data());
RtpCodec::inputFrame(_adts);
_adts = obtainFrame();
}
}//namespace mediakit