笔记：使用FFMpeg进行H264编码

转自：http://blog.csdn.net/eightdegree/article/details/7425635

 

使用FFMpeg可以很方便的对音视频进行编码，并且写文件。

    下面的代码是将5幅1280*720大小的图片进行编码，并且写到文件中。

    代码有些乱，但希望能抛砖引玉，对学习这方面的朋友有帮助。

 

CFile file[5];BYTE *szTxt[5];int nWidth = 0;int nHeight= 0;int nDataLen=0;int nLen;CString csFileName;for (int fileI = 1; fileI <= 5; fileI ++){  csFileName.Format("e:\\pics\\%d.bmp", fileI);  file[fileI - 1].Open(csFileName,CFile::modeRead | CFile::typeBinary);  nLen = file[fileI - 1].GetLength();  szTxt[fileI -1] = new BYTE[nLen];  file[fileI - 1].Read(szTxt[fileI - 1], nLen);  file[fileI - 1].Close();  //BMP bmi;//BITMAPINFO bmi;  //int nHeadLen = sizeof(BMP);  BITMAPFILEHEADER bmpFHeader;  BITMAPINFOHEADER bmpIHeader;  memcpy(&bmpFHeader,szTxt[fileI -1],sizeof(BITMAPFILEHEADER));  int nHeadLen = bmpFHeader.bfOffBits - sizeof(BITMAPFILEHEADER);  memcpy(&bmpIHeader,szTxt[fileI - 1]+sizeof(BITMAPFILEHEADER),nHeadLen);nWidth = bmpIHeader.biWidth;// 464;// bmi.bmpInfo.bmiHeader.biWidth;// ;  nHeight = bmpIHeader.biHeight;//362;// bmi.bmpInfo.bmiHeader.biHeight;// ;  szTxt[fileI - 1] += bmpFHeader.bfOffBits;  nDataLen = nLen-bmpFHeader.bfOffBits;}av_register_all();avcodec_register_all();AVFrame *m_pRGBFrame =  new AVFrame[1];  //RGB帧数据  AVFrame *m_pYUVFrame = new AVFrame[1];;  //YUV帧数据AVCodecContext *c= NULL;AVCodecContext *in_c= NULL;AVCodec *pCodecH264; //编码器uint8_t * yuv_buff;////查找h264编码器pCodecH264 = avcodec_find_encoder(CODEC_ID_H264);if(!pCodecH264){  fprintf(stderr, "h264 codec not found\n");  exit(1);}c= avcodec_alloc_context3(pCodecH264);c->bit_rate = 3000000;// put sample parameters c->width =nWidth;// c->height = nHeight;// // frames per second AVRational rate;rate.num = 1;rate.den = 25;c->time_base= rate;//(AVRational){1,25};c->gop_size = 10; // emit one intra frame every ten frames c->max_b_frames=1;c->thread_count = 1;c->pix_fmt = PIX_FMT_YUV420P;//PIX_FMT_RGB24;//av_opt_set(c->priv_data, /*"preset"*/"libvpx-1080p.ffpreset", /*"slow"*/NULL, 0);//打开编码器if(avcodec_open2(c,pCodecH264,NULL)<0)  TRACE("不能打开编码库");int size = c->width * c->height;yuv_buff = (uint8_t *) malloc((size * 3) / 2); // size for YUV 420 //将rgb图像数据填充rgb帧uint8_t * rgb_buff = new uint8_t[nDataLen];//图象编码int outbuf_size=100000;uint8_t * outbuf= (uint8_t*)malloc(outbuf_size); int u_size = 0;FILE *f=NULL; char * filename = "e:\\pics\\myData.h264";f = fopen(filename, "wb");if (!f){  TRACE( "could not open %s\n", filename);  exit(1);}//初始化SwsContextSwsContext * scxt = sws_getContext(c->width,c->height,PIX_FMT_BGR24,c->width,c->height,PIX_FMT_YUV420P,SWS_POINT,NULL,NULL,NULL);AVPacket avpkt;//AVFrame *pTFrame=new AVFramefor (int i=0;i<250;++i){  //AVFrame *m_pYUVFrame = new AVFrame[1];    int index = (i / 25) % 5;  memcpy(rgb_buff,szTxt[index],nDataLen);  avpicture_fill((AVPicture*)m_pRGBFrame, (uint8_t*)rgb_buff, PIX_FMT_RGB24, nWidth, nHeight);    //将YUV buffer 填充YUV Frame  avpicture_fill((AVPicture*)m_pYUVFrame, (uint8_t*)yuv_buff, PIX_FMT_YUV420P, nWidth, nHeight);  // 翻转RGB图像  m_pRGBFrame->data[0]  += m_pRGBFrame->linesize[0] * (nHeight - 1);  m_pRGBFrame->linesize[0] *= -1;                     m_pRGBFrame->data[1]  += m_pRGBFrame->linesize[1] * (nHeight / 2 - 1);  m_pRGBFrame->linesize[1] *= -1;  m_pRGBFrame->data[2]  += m_pRGBFrame->linesize[2] * (nHeight / 2 - 1);  m_pRGBFrame->linesize[2] *= -1;  //将RGB转化为YUV  sws_scale(scxt,m_pRGBFrame->data,m_pRGBFrame->linesize,0,c->height,m_pYUVFrame->data,m_pYUVFrame->linesize);    int got_packet_ptr = 0;  av_init_packet(&avpkt);  avpkt.data = outbuf;  avpkt.size = outbuf_size;  u_size = avcodec_encode_video2(c, &avpkt, m_pYUVFrame, &got_packet_ptr);  if (u_size == 0)  {   fwrite(avpkt.data, 1, avpkt.size, f);  }}fclose(f); delete []m_pRGBFrame;delete []m_pYUVFrame;delete []rgb_buff;free(outbuf);avcodec_close(c);av_free(c);