284 lines
10 KiB
C++
284 lines
10 KiB
C++
/*
|
||
* MIT License
|
||
*
|
||
* Copyright (c) 2016-2019 xiongziliang <771730766@qq.com>
|
||
* Copyright (c) 2019 火宣 <459502659@qq.com>
|
||
*
|
||
* This file is part of ZLMediaKit(https://github.com/xiongziliang/ZLMediaKit).
|
||
*
|
||
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
||
* of this software and associated documentation files (the "Software"), to deal
|
||
* in the Software without restriction, including without limitation the rights
|
||
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||
* copies of the Software, and to permit persons to whom the Software is
|
||
* furnished to do so, subject to the following conditions:
|
||
*
|
||
* The above copyright notice and this permission notice shall be included in all
|
||
* copies or substantial portions of the Software.
|
||
*
|
||
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
||
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
||
* SOFTWARE.
|
||
*/
|
||
|
||
#include "H264Rtp.h"
|
||
|
||
namespace mediakit{
|
||
|
||
|
||
typedef struct {
|
||
unsigned forbidden_zero_bit :1;
|
||
unsigned nal_ref_idc :2;
|
||
unsigned type :5;
|
||
} NALU;
|
||
|
||
typedef struct {
|
||
unsigned S :1;
|
||
unsigned E :1;
|
||
unsigned R :1;
|
||
unsigned type :5;
|
||
} FU;
|
||
|
||
static bool MakeNalu(uint8_t in, NALU &nal) {
|
||
nal.forbidden_zero_bit = in >> 7;
|
||
if (nal.forbidden_zero_bit) {
|
||
return false;
|
||
}
|
||
nal.nal_ref_idc = (in & 0x60) >> 5;
|
||
nal.type = in & 0x1f;
|
||
return true;
|
||
}
|
||
static bool MakeFU(uint8_t in, FU &fu) {
|
||
fu.S = in >> 7;
|
||
fu.E = (in >> 6) & 0x01;
|
||
fu.R = (in >> 5) & 0x01;
|
||
fu.type = in & 0x1f;
|
||
if (fu.R != 0) {
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
H264RtpDecoder::H264RtpDecoder() {
|
||
_h264frame = obtainFrame();
|
||
}
|
||
|
||
H264Frame::Ptr H264RtpDecoder::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<H264Frame>::obtainObj();
|
||
frame->buffer.clear();
|
||
frame->iPrefixSize = 4;
|
||
return frame;
|
||
}
|
||
|
||
bool H264RtpDecoder::inputRtp(const RtpPacket::Ptr &rtp, bool key_pos) {
|
||
key_pos = decodeRtp(rtp);
|
||
RtpCodec::inputRtp(rtp, key_pos);
|
||
return key_pos;
|
||
}
|
||
|
||
bool H264RtpDecoder::decodeRtp(const RtpPacket::Ptr &rtppack) {
|
||
/**
|
||
* h264帧类型
|
||
* Type==1:P/B frame
|
||
* Type==5:IDR frame
|
||
* Type==6:SEI frame
|
||
* Type==7:SPS frame
|
||
* Type==8:PPS frame
|
||
*/
|
||
/*
|
||
RTF3984 5.2节 Common Structure of the RTP Payload Format
|
||
Table 1. Summary of NAL unit types and their payload structures
|
||
|
||
Type Packet Type name Section
|
||
---------------------------------------------------------
|
||
0 undefined -
|
||
1-23 NAL unit Single NAL unit packet per H.264 5.6
|
||
24 STAP-A Single-time aggregation packet 5.7.1
|
||
25 STAP-B Single-time aggregation packet 5.7.1
|
||
26 MTAP16 Multi-time aggregation packet 5.7.2
|
||
27 MTAP24 Multi-time aggregation packet 5.7.2
|
||
28 FU-A Fragmentation unit 5.8
|
||
29 FU-B Fragmentation unit 5.8
|
||
30-31 undefined -
|
||
|
||
|
||
*/
|
||
const uint8_t *frame = (uint8_t *) rtppack->data() + rtppack->offset;
|
||
int length = rtppack->size() - rtppack->offset;
|
||
NALU nal;
|
||
MakeNalu(*frame, nal);
|
||
|
||
if (nal.type >= 0 && nal.type < 24) {
|
||
//a full frame
|
||
_h264frame->buffer.assign("\x0\x0\x0\x1", 4);
|
||
_h264frame->buffer.append((char *)frame, length);
|
||
_h264frame->timeStamp = rtppack->timeStamp;
|
||
auto key = _h264frame->keyFrame();
|
||
onGetH264(_h264frame);
|
||
return (key); //i frame
|
||
}
|
||
|
||
switch (nal.type){
|
||
case 24:{
|
||
// 24 STAP-A 单一时间的组合包
|
||
bool haveIDR = false;
|
||
auto ptr = frame + 1;
|
||
while(true){
|
||
int off = ptr - frame;
|
||
if (off >= length) {
|
||
break;
|
||
}
|
||
//获取当前nalu的大小
|
||
uint16_t len = *ptr++;
|
||
len <<= 8;
|
||
len |= *ptr++;
|
||
if (off + len > length) {
|
||
break;
|
||
}
|
||
if(len >= 10){
|
||
//过小的帧丢弃
|
||
NALU nal;
|
||
MakeNalu(ptr[0], nal);
|
||
_h264frame->buffer.assign("\x0\x0\x0\x1", 4);
|
||
_h264frame->buffer.append((char *)ptr, len);
|
||
_h264frame->timeStamp = rtppack->timeStamp;
|
||
if(nal.type == H264Frame::NAL_IDR){
|
||
haveIDR = true;
|
||
}
|
||
onGetH264(_h264frame);
|
||
}
|
||
ptr += len;
|
||
}
|
||
return haveIDR;
|
||
}
|
||
|
||
case 28:{
|
||
//FU-A
|
||
FU fu;
|
||
MakeFU(frame[1], fu);
|
||
if (fu.S) {
|
||
//该帧的第一个rtp包 FU-A start
|
||
char tmp = (nal.forbidden_zero_bit << 7 | nal.nal_ref_idc << 5 | fu.type);
|
||
_h264frame->buffer.assign("\x0\x0\x0\x1", 4);
|
||
_h264frame->buffer.push_back(tmp);
|
||
_h264frame->buffer.append((char *)frame + 2, length - 2);
|
||
_h264frame->timeStamp = rtppack->timeStamp;
|
||
//该函数return时，保存下当前sequence,以便下次对比seq是否连续
|
||
_lastSeq = rtppack->sequence;
|
||
return _h264frame->keyFrame();
|
||
}
|
||
|
||
if (rtppack->sequence != _lastSeq + 1 && rtppack->sequence != 0) {
|
||
//中间的或末尾的rtp包，其seq必须连续(如果回环了则判定为连续)，否则说明rtp丢包，那么该帧不完整，必须得丢弃
|
||
_h264frame->buffer.clear();
|
||
WarnL << "rtp sequence不连续: " << rtppack->sequence << " != " << _lastSeq << " + 1,该帧被废弃";
|
||
return false;
|
||
}
|
||
|
||
if (!fu.E) {
|
||
//该帧的中间rtp包 FU-A mid
|
||
_h264frame->buffer.append((char *)frame + 2, length - 2);
|
||
//该函数return时，保存下当前sequence,以便下次对比seq是否连续
|
||
_lastSeq = rtppack->sequence;
|
||
return false;
|
||
}
|
||
|
||
//该帧最后一个rtp包 FU-A end
|
||
_h264frame->buffer.append((char *)frame + 2, length - 2);
|
||
_h264frame->timeStamp = rtppack->timeStamp;
|
||
auto key = _h264frame->keyFrame();
|
||
onGetH264(_h264frame);
|
||
return key;
|
||
}
|
||
|
||
default:{
|
||
// 29 FU-B 单NAL单元B模式
|
||
// 25 STAP-B 单一时间的组合包
|
||
// 26 MTAP16 多个时间的组合包
|
||
// 27 MTAP24 多个时间的组合包
|
||
// 0 udef
|
||
// 30 udef
|
||
// 31 udef
|
||
WarnL << "不支持的rtp类型:" << (int)nal.type << " " << rtppack->sequence;
|
||
return false;
|
||
}
|
||
}
|
||
}
|
||
|
||
void H264RtpDecoder::onGetH264(const H264Frame::Ptr &frame) {
|
||
//写入环形缓存
|
||
RtpCodec::inputFrame(frame);
|
||
_h264frame = obtainFrame();
|
||
}
|
||
|
||
|
||
////////////////////////////////////////////////////////////////////////
|
||
|
||
H264RtpEncoder::H264RtpEncoder(uint32_t ui32Ssrc,
|
||
uint32_t ui32MtuSize,
|
||
uint32_t ui32SampleRate,
|
||
uint8_t ui8PlayloadType,
|
||
uint8_t ui8Interleaved) :
|
||
RtpInfo(ui32Ssrc,
|
||
ui32MtuSize,
|
||
ui32SampleRate,
|
||
ui8PlayloadType,
|
||
ui8Interleaved) {
|
||
}
|
||
|
||
void H264RtpEncoder::inputFrame(const Frame::Ptr &frame) {
|
||
RtpCodec::inputFrame(frame);
|
||
|
||
GET_CONFIG(uint32_t,cycleMS,Rtp::kCycleMS);
|
||
auto pcData = frame->data() + frame->prefixSize();
|
||
auto uiStamp = frame->stamp();
|
||
auto iLen = frame->size() - frame->prefixSize();
|
||
unsigned char naluType = H264_TYPE(pcData[0]); //获取NALU的5bit 帧类型
|
||
|
||
uiStamp %= cycleMS;
|
||
int iSize = _ui32MtuSize - 2;
|
||
if (iLen > iSize) { //超过MTU
|
||
const unsigned char s_e_r_Start = 0x80;
|
||
const unsigned char s_e_r_Mid = 0x00;
|
||
const unsigned char s_e_r_End = 0x40;
|
||
//获取帧头数据，1byte
|
||
unsigned char nal_ref_idc = *((unsigned char *) pcData) & 0x60; //获取NALU的2bit 帧重要程度 00 可以丢 11不能丢
|
||
//nal_ref_idc = 0x60;
|
||
//组装FU-A帧头数据 2byte
|
||
unsigned char f_nri_type = nal_ref_idc + 28;//F为0 1bit,nri上面获取到2bit,28为FU-A分片类型5bit
|
||
unsigned char s_e_r_type = naluType;
|
||
bool bFirst = true;
|
||
bool mark = false;
|
||
int nOffset = 1;
|
||
while (!mark) {
|
||
if (iLen < nOffset + iSize) { //是否拆分结束
|
||
iSize = iLen - nOffset;
|
||
mark = true;
|
||
s_e_r_type = s_e_r_End + naluType;
|
||
} else if (bFirst) {
|
||
s_e_r_type = s_e_r_Start + naluType;
|
||
} else {
|
||
s_e_r_type = s_e_r_Mid + naluType;
|
||
}
|
||
memcpy(_aucSectionBuf, &f_nri_type, 1);
|
||
memcpy(_aucSectionBuf + 1, &s_e_r_type, 1);
|
||
memcpy(_aucSectionBuf + 2, (unsigned char *) pcData + nOffset, iSize);
|
||
nOffset += iSize;
|
||
makeH264Rtp(naluType,_aucSectionBuf, iSize + 2, mark,bFirst, uiStamp);
|
||
bFirst = false;
|
||
}
|
||
} else {
|
||
makeH264Rtp(naluType,pcData, iLen, true, true, uiStamp);
|
||
}
|
||
}
|
||
|
||
void H264RtpEncoder::makeH264Rtp(int nal_type,const void* data, unsigned int len, bool mark, bool first_packet, uint32_t uiStamp) {
|
||
RtpCodec::inputRtp(makeRtp(getTrackType(),data,len,mark,uiStamp),first_packet && nal_type == H264Frame::NAL_IDR);
|
||
}
|
||
|
||
}//namespace mediakit
|