分析一下GitHub上一份FLV文件分析和解析器的開源代碼
GitHub源碼地址：功能強大的 FLV 文件分析和解析器

：可以將flv文件的視頻tag中的h264類型數據和音頻tag中的aac類型數據導出
（只限h264和aac）
(這個代碼不太適合用于大文件的分析，因為所有數據都會一直存在內存中)

main.cpp

#include <iostream> #include <fstream> #include "FlvParser.h"using namespace std;void Pro(fstream &fin);int main() {cout << "Hello World!" << endl;string infilename("test.flv");if(!infilename.length()){cout<<"!infilename.length() "<<endl;}fstream fin;fin.open(infilename, ios_base::in | ios_base::binary);if(!fin){cout<<"fin.open failed!"<<endl;return 0;}Pro(fin);fin.close();return 0;}void Pro(fstream& fin) {FlvParser parser;int nBufSize = 2 * 1024 * 1024;int nFlvPos = 0;uint8_t *pBuf, *pBak;pBuf = new uint8_t[nBufSize];pBak = new uint8_t[nBufSize];while (1){int nReadNum = 0;int nUsedLen = 0;fin.read((char*)pBuf + nFlvPos, nBufSize - nFlvPos);//獲取上次讀取的字符數nReadNum = fin.gcount();//結束讀取if(nReadNum == 0)break;nFlvPos += nReadNum;parser.Parse(pBuf, nFlvPos, nUsedLen);//判斷沒有處理nFlvPos長度，就前移剩下的數據到前面if(nFlvPos != nUsedLen){memcpy(pBak, pBuf + nUsedLen, nFlvPos - nUsedLen);memcpy(pBuf, pBak, nFlvPos - nUsedLen);}nFlvPos -= nUsedLen;}//輸出文件信息parser.PrintInfo();//輸出h264數據parser.DumpH264("parser.h264");//輸出aac數據parser.DumpAAC("parser.aac");delete[] pBak;delete[] pBuf;}

FlvParser.h

#ifndef FLVPARSER_H #define FLVPARSER_H#include <vector> #include <stdint.h> #include <string>using namespace std;class FlvParser { public:FlvParser();virtual ~FlvParser();int Parse(uint8_t *pBuf, int nBufSize,int& nUsedLen);int PrintInfo();int DumpH264(const std::string& path);int DumpAAC(const std::string& path);private://flv頭部信息typedef struct _FlvHeader{int nVersion; //版本int bHaveVideo;//是否有音頻int bHaveAudio;//是否有視頻int nHeadSize;//FLV頭部長度//頭部數據uint8_t *pFlvHeader;}FlvHeader;//Tag頭部struct TagHeader{int nType;//類型int nDataSize;//body的大小int nTimeStamp;//時間戳int nTSEx; //時間戳的擴展字節int nStreamID;//流的ID,總是0//完整的時間戳nTimeStamp和nTSEx拼裝uint32_t nTotalTS;TagHeader():nType(0), nDataSize(0), nTimeStamp(0), nTSEx(0), nStreamID(0), nTotalTS(0){}~TagHeader(){}};class Tag{public:TagHeader _header;uint8_t* _pTagHeader;//tag頭部uint8_t* _pTagData;//tag bodyuint8_t* _pMedia;//tag 元數據，改造后的數據int _nMediaLen;//數據長度public:Tag():_pTagHeader(0), _pTagData(0), _pMedia(0), _nMediaLen(0){}void Init(TagHeader* pHeader, uint8_t* pBuf, int nLeftLen);};class VideoTag: public Tag{public:int _nFrameType;//幀類型int _nCodecID;//視頻編解碼類型public:VideoTag(TagHeader* pHeader, uint8_t* pBuf, int nLeftLen, FlvParser* pParser);int ParseH264Tag(FlvParser *pParser);int ParseH264Configuration(FlvParser* pParser, uint8_t* pTagData);int ParseNalu(FlvParser* pParser, uint8_t* pTagData);};class AudioTag:public Tag{public:int _nSoundFormat; //編碼類型int _nSoundRate;//采樣率int _nSoundSize;//精度int _nSoundType;//類型static int _aacProfile;//AAC profilestatic int _sampleRateIndex;//采樣率索引static int _channelConfig;//通道設置public:AudioTag(TagHeader* pHeader, uint8_t* pBuf, int nLeftLen, FlvParser* pParser);int ParseAACTag(FlvParser *pParser);int ParseAudioSpecificConfig(FlvParser* pParser, uint8_t *pTagData);int ParserRawAAC(FlvParser* pParser, uint8_t* pTagData);};class MetaDataTag: public Tag{public:uint8_t m_amf1_type;uint32_t m_amf1_size;uint8_t m_amf2_type;unsigned char* m_meta;unsigned int m_length;double m_duration;double m_width;double m_height;double m_videodatarate;double m_framerate;double m_videocodecid;double m_audiodatarate;double m_audiosamplerate;double m_audiosamplesize;bool m_stereo;double m_audiocodecid;string m_major_brand;string m_minor_version;string m_compatible_brands;string m_encoder;double m_filesize;public:MetaDataTag(TagHeader *pHeader, uint8_t *pBuf, int nLeftLen, FlvParser *pParser);double hexStr2double(const unsigned char* hex, const unsigned int length);int parseMeta(FlvParser* pParser);void printMeta();};struct FlvStat{int nMetaNum, nVideoNum, nAudioNum;int nMaxTimeStamp;int nLengthSize;FlvStat(): nMetaNum(0), nVideoNum(0), nAudioNum(0), nMaxTimeStamp(0), nLengthSize(0){}~FlvStat(){}};//取4字節數值static uint32_t ShowU32(uint8_t* pBuf){return (pBuf[0] << 24) | (pBuf[1] << 16) | (pBuf[2] << 8) | pBuf[3];}//取3字節數值static uint32_t ShowU24(uint8_t* pBuf){return (pBuf[0] << 16) | (pBuf[1] << 8) | pBuf[2];}//取2字節數值static uint32_t ShowU16(uint8_t* pBuf){return (pBuf[0] << 8) | pBuf[1];}//取1字節數值static uint32_t ShowU8(uint8_t* pBuf){return pBuf[0];}//按位的數據寫入到64位中，x 本來的值會往左移（高位移）//length : 多少位數據//value : 實際的值static void WriteU64(uint64_t& x, int length, int value){uint64_t mask = 0xFFFFFFFFFFFFFFFF >> (64 - length);x = (x << length) | ((uint64_t)value & mask);}//字節序替換static uint32_t WriteU32(uint32_t n){uint32_t nn = 0;uint8_t *p = (uint8_t*)&n;uint8_t *pp= (uint8_t*)&nn;pp[0] = p[3];pp[1] = p[2];pp[2] = p[1];pp[3] = p[0];return nn;}friend class Tag;private:FlvHeader* CreateFlvHeader(uint8_t* pBuf);int DestroyFlvHeader(FlvHeader* pHeader);Tag* CreateTag(uint8_t* pBuf, int nLeftLen);int DestroyTag(Tag* pTag);int Stat();int StatVideo(Tag* pTag);int IsUserDataTag(Tag* pTag);private:FlvHeader* _pFlvHeader;vector<Tag*> _vpTag;FlvStat _sStat;//Videojj* _vjj;//h264int _nNaluUintLength;};#endif // FLVPARSER_H

FlvParser.cpp

#include "FlvParser.h" #include <iostream> #include <fstream> #include <string.h>using namespace std;#define CheckBuffer(x) { if((nBufSize - nOffset) < (x)){ nUsedLen = nOffset; return 0;} }int FlvParser::AudioTag::_aacProfile; int FlvParser::AudioTag::_sampleRateIndex; int FlvParser::AudioTag::_channelConfig;static const uint32_t nH264StartCode = 0x01000000;FlvParser::FlvParser() {_pFlvHeader = NULL;}FlvParser::~FlvParser() {for(int i = 0; i < _vpTag.size(); i++){DestroyTag(_vpTag[i]);delete _vpTag[i];}}int FlvParser::Parse(uint8_t *pBuf, int nBufSize,int& nUsedLen) {int nOffset = 0;//初始化flv解析器if(_pFlvHeader == 0){//CheckBuffer(9);//如果不夠flv header長度就返回if((nBufSize - nOffset) < 9){nUsedLen = nOffset;return 0;}_pFlvHeader = CreateFlvHeader(pBuf + nOffset);nOffset += _pFlvHeader->nHeadSize;}while (1){//CheckBuffer(15);if((nBufSize - nOffset) < 15){nUsedLen = nOffset;return 0;}int nPrevSize = ShowU32(pBuf + nOffset);nOffset += 4;//移過4個字節的PreviousTagSizeTag* pTag = CreateTag(pBuf + nOffset, nBufSize - nOffset);if(pTag == NULL){nOffset -= 4;break;}nOffset += (11 + pTag->_header.nDataSize);_vpTag.push_back(pTag);}nUsedLen = nOffset;return 0; }int FlvParser::PrintInfo() {Stat();cout << "vnum: " << _sStat.nVideoNum << " , anum: " << _sStat.nAudioNum << " , mnum: " << _sStat.nMetaNum << endl;cout << "maxTimeStamp: " << _sStat.nMaxTimeStamp << " ,nLengthSize: " << _sStat.nLengthSize << endl;return 0; }//輸出h264文件 int FlvParser::DumpH264(const std::string& path) {fstream f;f.open(path.c_str(), ios_base::out | ios_base::binary);vector<Tag*>::iterator it_tag;for(it_tag = _vpTag.begin(); it_tag != _vpTag.end(); it_tag++){if((*it_tag)->_header.nType != 0x09)continue;f.write((char*)(*it_tag)->_pMedia, (*it_tag)->_nMediaLen);}f.close();return 1; }//輸出AAC文件 int FlvParser::DumpAAC(const std::string& path) {fstream f;f.open(path.c_str(), ios_base::out | ios_base::binary);vector<Tag*>::iterator it_tag;for(it_tag = _vpTag.begin(); it_tag != _vpTag.end(); it_tag ++){if((*it_tag)->_header.nType != 0x08){continue;}AudioTag* pAudioTag = (AudioTag*)(*it_tag);if(pAudioTag->_nSoundFormat != 10)//不是AACcontinue;if(pAudioTag->_nMediaLen != 0){f.write((char*)(*it_tag)->_pMedia, (*it_tag)->_nMediaLen);}}f.close();return 1; }//創建保存Flv Header信息 FlvParser::FlvHeader* FlvParser::CreateFlvHeader(uint8_t *pBuf) {FlvHeader* pHeader = new FlvHeader;pHeader->nVersion = pBuf[3]; //版本號pHeader->bHaveAudio = (pBuf[4] >> 2) & 0x01;//是否有音頻pHeader->bHaveVideo = (pBuf[4] >> 0) & 0x01;//是否有視頻pHeader->nHeadSize = ShowU32(pBuf + 5);// 頭部長度//將原來的flv header 數據保存一份pHeader->pFlvHeader = new uint8_t[pHeader->nHeadSize];memcpy(pHeader->pFlvHeader, pBuf, pHeader->nHeadSize);return pHeader; }//釋放Flv Header信息相關內存 int FlvParser::DestroyFlvHeader(FlvHeader *pHeader) {if(pHeader == NULL)return 0;delete pHeader->pFlvHeader;delete pHeader;pHeader = NULL;return 1; }int FlvParser::Stat() {for(int i = 0; i< _vpTag.size(); i++){switch (_vpTag[i]->_header.nType){case 0x08:_sStat.nAudioNum++;break;case 0x09:StatVideo(_vpTag[i]);break;case 0x12:_sStat.nMetaNum++;break;default:break;}}return 1; }int FlvParser::StatVideo(Tag *pTag) {_sStat.nVideoNum++;_sStat.nMaxTimeStamp = pTag->_header.nTimeStamp;//0x17 = 幀類型為 1 (h264的IDR 關鍵幀標識)// 7 (avc)//0x00 = AVC 包類型為 0 （AVC sequence header）if(pTag->_pTagData[0] == 0x17 && pTag->_pTagData[1] == 0x00){//獲取nalu 長度使用多少個字節表示//注意：根據上面知道AVC sequence header包（包含SPS 、PPS）時，//幀類型是 1 ，是使用h264的IDR 關鍵幀相同標識的）_sStat.nLengthSize = (pTag->_pTagData[9] & 0x03) + 1;}return 1; }//創建Tag FlvParser::Tag* FlvParser::CreateTag(uint8_t *pBuf, int nLeftLen) {//開始解析tag頭部TagHeader header;header.nType = ShowU8(pBuf + 0);//類型header.nDataSize = ShowU24(pBuf + 1);//tag body的長度header.nTimeStamp = ShowU24(pBuf + 4);//時間戳，低24位header.nTSEx = ShowU8(pBuf + 7);//時間戳擴展字段，高8位header.nStreamID = ShowU24(pBuf + 8);//流的idheader.nTotalTS = (uint32_t)((header.nTSEx << 24)) + header.nTimeStamp;//合成完整的時間戳//如果這次數據不夠整個tag長度（包括tag header 和 tag body）就不處理if((header.nDataSize + 11) > nLeftLen){return NULL;}Tag* pTag;switch (header.nType) {case 0x09://視頻類型pTag = new VideoTag(&header, pBuf, nLeftLen, this);break;case 0x08://音頻類型pTag = new AudioTag(&header, pBuf, nLeftLen, this);break;case 0x12://script 類型pTag = new MetaDataTag(&header, pBuf, nLeftLen, this);break;default:pTag = new Tag();pTag->Init(&header, pBuf, nLeftLen);break;}return pTag;}//釋放Tag相應的內存 int FlvParser::DestroyTag(Tag* pTag) {if(pTag->_pMedia != NULL)delete[] pTag->_pMedia;if(pTag->_pTagData != NULL)delete[] pTag->_pTagData;if(pTag->_pTagHeader != NULL)delete[] pTag->_pTagHeader;return 1; }//tag 初始化 void FlvParser::Tag::Init(TagHeader *pHeader, uint8_t *pBuf, int nLeftLen) {//復制tag頭部信息(解析好的)memcpy(&_header, pHeader, sizeof(TagHeader));//復制tag頭部信息（原數據）_pTagHeader = new uint8_t[11];memcpy(_pTagHeader, pBuf, 11);//復制tag body_pTagData = new uint8_t[_header.nDataSize];memcpy(_pTagData, pBuf + 11, _header.nDataSize); }FlvParser::MetaDataTag::MetaDataTag(TagHeader *pHeader, uint8_t *pBuf, int nLeftLen, FlvParser *pParser) {Init(pHeader, pBuf, nLeftLen);uint8_t* pd = _pTagData;m_amf1_type = ShowU8(pd);//第一個AMF 包類型一般為2（字符串）m_amf1_size = ShowU16(pd + 1);//字符串數據的長度//不是字符串就返回，不處理if(m_amf1_type != 2){printf("no metadata\n");return;}//判斷字符串是否等于onMetaData就進行處理if(strncmp((const char*)"onMetaData", (const char*)(pd + 3), 10) == 0){parseMeta(pParser);}}//使用字符串的方式提取double類型值，直接將原來的double8個字節，字節序調轉一下也一樣的 double FlvParser::MetaDataTag::hexStr2double(const unsigned char* hex, const unsigned int length) {double ret = 0; #if 0char hexstr[length * 2];memset(hexstr, 0, sizeof(hexstr));for(uint32_t i = 0; i < length; i++){sprintf(hexstr + i * 2, "%02x", hex[i]);}sscanf(hexstr, "%llx", (unsigned long long*)&ret); #elseret = *(double*)hex;uint8_t* ret_begin = (uint8_t*)&ret;uint8_t* ret_end = ret_begin + 7;for(int i = 0; i<4; i++){uint8_t temp = *ret_begin;*ret_begin = *ret_end;*ret_end = temp;ret_begin++;ret_end--;}#endifreturn ret; }int FlvParser::MetaDataTag::parseMeta(FlvParser* pParser) {uint8_t* pd = _pTagData;int dataSize = _header.nDataSize;uint32_t arrayLen = 0;//跨過第一個AMF結構，到第二個AFM結構uint32_t offset = 13;uint32_t nameLen = 0;double doubleValue = 0;string strValue = "";bool boolValue = false;uint32_t valueLen =0;uint8_t u8Value = 0;//判斷類型是否等于8（數組）if(pd[offset++] == 0x08){//數組元素長度arrayLen = ShowU32(pd + offset);offset += 4;//跨過數組長度占用的4個字節cout<<"MetaData ArrayLen = " << arrayLen << endl;}else{cout<<"MetaData format error!" <<endl;return -1;}for(uint32_t i = 0; i < arrayLen; i++){doubleValue = 0;boolValue = false;strValue = "";//讀取字段名稱的長度nameLen = ShowU16(pd + offset);offset += 2;char name[nameLen + 1];//字段存儲memset(name, 0, sizeof(name));//復制字段名稱memcpy(name, &pd[offset], nameLen);offset += nameLen;//獲取AFM類型uint8_t amfType = pd[offset++];switch (amfType) {case 0x0://double 8字節doubleValue = hexStr2double(&pd[offset], 8);offset += 8;break;case 0x1: //bool 1個字節u8Value = ShowU8(pd + offset);offset += 1;if(u8Value != 0)boolValue = true;elseboolValue = false;break;case 0x2://字符串valueLen = ShowU16(pd + offset);offset += 2;strValue.append(pd + offset, pd + offset + valueLen);strValue.append("");offset += valueLen;break;default:printf("un handle amfType:%d\n", amfType);break;}//保存相應的參數值if(strncmp(name, "duration", 8) == 0){m_duration = doubleValue;}else if(strncmp(name, "width", 5) == 0){m_width = doubleValue;}else if(strncmp(name, "height", 6) == 0){m_height = doubleValue;}else if(strncmp(name, "videodatarate", 13) == 0){m_videodatarate = doubleValue;}else if(strncmp(name, "framerate", 9) == 0){m_framerate = doubleValue;}else if(strncmp(name, "videocodecid", 12) == 0){m_videocodecid = doubleValue;}else if(strncmp(name, "audiodatarate", 13) == 0){m_audiodatarate = doubleValue;}else if(strncmp(name, "audiosamplerate", 15) == 0){m_audiosamplerate = doubleValue;}else if(strncmp(name, "audiosamplesize", 15) == 0){m_audiosamplesize = doubleValue;}else if(strncmp(name, "stereo", 6) == 0){m_stereo = boolValue;}else if(strncmp(name, "audiocodecid", 12) == 0){m_audiocodecid = doubleValue;}else if(strncmp(name, "major_brand", 11) == 0){m_major_brand = strValue;}else if(strncmp(name, "minor_version", 13) == 0){m_minor_version = strValue;}else if(strncmp(name, "compatible_brands", 17) == 0){m_compatible_brands = strValue;}else if(strncmp(name, "encoder", 7) == 0){m_encoder = strValue;}else if(strncmp(name, "filesize", 8) == 0){m_filesize = doubleValue;}}printMeta();return 1; }void FlvParser::MetaDataTag::printMeta() {printf("\nduration: %0.2lfs, filesize: %.0lfbytes\n", m_duration, m_filesize);printf("width: %0.0lf, height: %0.0lf\n", m_width, m_height);printf("videodatarate: %0.2lfkbps, framerate: %0.0lffps\n", m_videodatarate, m_framerate);printf("videocodecid: %0.0lf\n", m_videocodecid);printf("audiodatarate: %0.2lfkbps, audiosamplerate: %0.0lfKhz\n",m_audiodatarate, m_audiosamplerate);printf("audiosamplesize: %0.0lfbit, stereo: %d\n", m_audiosamplesize, m_stereo);printf("audiocodecid: %0.0lf\n", m_audiocodecid);printf("major_brand: %s, minor_version: %s\n", m_major_brand.c_str(), m_minor_version.c_str());printf("compatible_brands: %s, encoder: %s\n\n", m_compatible_brands.c_str(), m_encoder.c_str()); }FlvParser::AudioTag::AudioTag(TagHeader* pHeader, uint8_t* pBuf, int nLeftLen, FlvParser* pParser) {Init(pHeader, pBuf, nLeftLen);uint8_t *pd = _pTagData;_nSoundFormat = (pd[0] & 0xf0) >> 4;//音頻格式 如：AAC_nSoundRate = (pd[0] & 0x0c) >> 2;//采樣率_nSoundSize = (pd[0] & 0x02) >> 1;//采樣精度_nSoundType = (pd[0] & 0x01);//是否立體聲if(_nSoundFormat == 10)//AAC{ParseAACTag(pParser);}}int FlvParser::AudioTag::ParseAACTag(FlvParser *pParser) {uint8_t* pd = _pTagData;//數據包的類型：音頻配置信息，音頻數據int nAACPacketType = pd[1];//AAC sequence headerif(nAACPacketType == 0){ParseAudioSpecificConfig(pParser, pd);}//AAC 數據（AAC RAW）else if(nAACPacketType == 1){ParserRawAAC(pParser, pd);}else{cout<<"ParseAACTag nAACPacketType = "<< nAACPacketType << endl;}return 1; }int FlvParser::AudioTag::ParseAudioSpecificConfig(FlvParser* pParser, uint8_t *pTagData) {uint8_t* pd = _pTagData;_aacProfile = ((pd[2] & 0xf8) >> 3);//5位 AAC 編碼級別_sampleRateIndex = ((pd[2] & 0x07) << 1) | (pd[3] >> 7);//4bit 真正采樣率索引_channelConfig = (pd[3] >> 3) & 0x0f; //4bit 通道數量printf("----- AAC info------\n");printf("profile:%d\n", _aacProfile);printf("sample rate index:%d\n", _sampleRateIndex);printf("channel config:%d\n", _channelConfig);_pMedia = NULL;_nMediaLen = 0;return 0; }int FlvParser::AudioTag::ParserRawAAC(FlvParser* pParser, uint8_t* pTagData) {uint64_t bits = 0;//數據長度，跳過tag data的第一個第二個字節int dataSize = _header.nDataSize - 2;//制作 AAC ADTSWriteU64(bits, 12, 0xFFF);WriteU64(bits, 1, 0);WriteU64(bits, 2, 0);WriteU64(bits, 1, 1);WriteU64(bits, 2, _aacProfile - 1);WriteU64(bits, 4, _sampleRateIndex);WriteU64(bits, 1, 0);WriteU64(bits, 3, _channelConfig);WriteU64(bits, 1, 0);WriteU64(bits, 1, 0);WriteU64(bits, 1, 0);WriteU64(bits, 1, 0);WriteU64(bits, 13, 7 + dataSize);WriteU64(bits, 11, 0x7FF);WriteU64(bits, 2, 0);//_nMediaLen = 7 + dataSize;_pMedia = new uint8_t[_nMediaLen];uint8_t p64[8];//調轉字節序p64[0] = (uint8_t)(bits >> 56);//0,沒用數據p64[1] = (uint8_t)(bits >> 48);//ADTS 頭的0xfff開始位置p64[2] = (uint8_t)(bits >> 40);p64[3] = (uint8_t)(bits >> 32);p64[4] = (uint8_t)(bits >> 24);p64[5] = (uint8_t)(bits >> 16);p64[6] = (uint8_t)(bits >> 8);p64[7] = (uint8_t)(bits);//ADTS header，從p64 + 1 開始的memcpy(_pMedia, p64 + 1, 7);//AAC RAW 從 audio tag data的第3個字節開始的memcpy(_pMedia + 7, pTagData + 2, dataSize);return 1; }//VideoTag構造 FlvParser::VideoTag::VideoTag(TagHeader* pHeader, uint8_t* pBuf, int nLeftLen, FlvParser* pParser) {//初始化Init(pHeader, pBuf, nLeftLen);uint8_t *pd = _pTagData;_nFrameType = (pd[0] & 0xf0) >> 4;//幀類型 (HDR / 普通幀)_nCodecID = pd[0] & 0x0f;//視頻編碼類型(avc)//開始解析 (視頻類型 的tag 、 avc 編碼類型)if(_header.nType == 0x09 && _nCodecID == 7){ParseH264Tag(pParser);} }//解析h264 FlvParser::VideoTag::ParseH264Tag(FlvParser *pParser) {uint8_t* pd = _pTagData;int nAVCPacketType = pd[1];int nCompositionTime = FlvParser::ShowU24(pd + 2);//視頻配置信息（sps、pps）if(nAVCPacketType == 0){ParseH264Configuration(pParser, pd);}//視頻數據else if(nAVCPacketType == 1){ParseNalu(pParser, pd);}else{cout<<"Unknow ParseH264Tag nAVCPacketType = "<< nAVCPacketType << endl;}return 1;}FlvParser::VideoTag::ParseH264Configuration(FlvParser *pParser, uint8_t *pTagData) {uint8_t* pd = pTagData;//獲取nalu長度使用多少個字節進行存儲pParser->_nNaluUintLength = (pd[9] & 0x03) + 1;int sps_size, pps_size;//sps(序列參數集)的長度sps_size = FlvParser::ShowU16(pd + 11);//pps(圖像參數集)的長度pps_size = FlvParser::ShowU16(pd + 11 + (2 + sps_size) + 1);//制作元數據(4表示start code)_nMediaLen = 4 + sps_size + 4 + pps_size;_pMedia = new uint8_t[_nMediaLen];memcpy(_pMedia, &nH264StartCode, 4);memcpy(_pMedia + 4, pd + 11 + 2, sps_size);memcpy(_pMedia + 4 + sps_size, &nH264StartCode, 4);memcpy(_pMedia + 4 + sps_size + 4, pd + 11 + 2 + sps_size + 2 + 1, pps_size);return 1; }FlvParser::VideoTag::ParseNalu(FlvParser *pParser, uint8_t *pTagData) {uint8_t* pd = pTagData;int nOffset = 0;_pMedia = new uint8_t[_header.nDataSize + 10];_nMediaLen = 0;nOffset = 5;while (1){//如果解析完了一個TAG，就跳出循環if(nOffset >= _header.nDataSize)break;//計算nalu的長度//一個tag可能包含多個nalu,每個nalu前面都有NalUnitLength字節表示每個nalu的長度int nNaluLen;switch (pParser->_nNaluUintLength){case 4:nNaluLen = FlvParser::ShowU32(pd + nOffset);break;case 3:nNaluLen = FlvParser::ShowU24(pd + nOffset);break;case 2:nNaluLen = FlvParser::ShowU16(pd + nOffset);break;default:nNaluLen = FlvParser::ShowU8(pd + nOffset);break;}//添加nalu start codememcpy(_pMedia + _nMediaLen, &nH264StartCode, 4);//復制nalu數據memcpy(_pMedia + _nMediaLen + 4, pd + nOffset + pParser->_nNaluUintLength, nNaluLen);_nMediaLen += (4 + nNaluLen);nOffset += (pParser->_nNaluUintLength + nNaluLen);} } 創作挑戰賽新人創作獎勵來咯，堅持創作打卡瓜分現金大獎

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