ffmpeg--编码解码h264

YUV转H264

代码如下：

#define   _WIDTH   352   #define    _HEIGHT 288   void CEncodeYUVDlg::OnButEncode()   {   // TODO: Add your control notification handler code here      uint8_t *video_outbuf;   int video_outbuf_size, out_size;      /* alloc image and output buffer */      video_outbuf_size = 10000000;      video_outbuf = (unsigned char *)malloc(video_outbuf_size);        av_register_all();   avcodec_init();   unsigned char  sYUV_data[_WIDTH*_HEIGHT*3/2];   AVCodecContext *pContext = avcodec_alloc_context();   /* put sample parameters */      pContext->codec_id = CODEC_ID_H264;  //也可设其他类型，如：CODEC_ID_MPEG1VIDEO，但参数需更改，如：400K码率，10的帧率，就会崩溃。  pContext->codec_type = CODEC_TYPE_VIDEO;    pContext->bit_rate = 400000;    pContext->width = _WIDTH;    pContext->height = _HEIGHT;    pContext->time_base.den = 25;    pContext->time_base.num = 1;    pContext->gop_size = 25;       pContext->pix_fmt = PIX_FMT_YUV420P;   pContext->dct_algo = 0;    pContext->me_pre_cmp=2;    pContext->cqp = 26;    pContext->me_method =7;    pContext->qmin = 3;    pContext->qmax = 31;    pContext->max_qdiff = 3;    pContext->qcompress = 0.5;    pContext->qblur = 0.5;    pContext->nsse_weight = 8;    pContext->i_quant_factor = (float)0.8;    pContext->b_quant_factor = 1.25;    pContext->b_quant_offset = 1.25;   /* find the mpeg1 video encoder */      AVCodec* codec = avcodec_find_encoder(pContext->codec_id);      avcodec_open(pContext, codec);            AVFrame* g_pInFrame = avcodec_alloc_frame();     int isize = pContext->width * pContext->height;   g_pInFrame->data[0] = sYUV_data;      g_pInFrame->data[1] = g_pInFrame->data[0] + isize;   g_pInFrame->data[2] = g_pInFrame->data[1] + isize / 4;   g_pInFrame->linesize[0] = pContext->width;   g_pInFrame->linesize[1] = pContext->width / 2;   g_pInFrame->linesize[2] = pContext->width / 2;     FILE* fp = fopen("01.mov","rb");   int nread = -1;   if (fp!=NULL)   {    while(nread!=0)    {          nread = fread(sYUV_data,1,_WIDTH*_HEIGHT*3/2,fp);       out_size = avcodec_encode_video(pContext, video_outbuf, video_outbuf_size, g_pInFrame);        if (out_size>0)       {        FILE* ff = fopen("1.mov","ab");        if (ff!=NULL)        {         fwrite(video_outbuf,1,out_size,ff);         fclose(ff);        }       }    }    fclose(fp);    AfxMessageBox("Encode Over!");   }  }  

 

H264转YUV

有一帧H264码流，如何变成YUV数据。
ffmpeg解码

代码如下：

avcodec_init();   av_register_all();  AVCodec* m_pCodec=avcodec_find_decoder(CODEC_ID_H264);  if(NULL==m_pCodec)  return FALSE;  AVCodecContext* m_pContext = avcodec_alloc_context();  AVFrame* m_pFrame = avcodec_alloc_frame();  if(NULL==m_pContext ||NULL==m_pFrame)  return FALSE;  if (avcodec_open(m_pContext, m_pCodec) < 0)  {  return FALSE;  }   int nWidth = 352; int nHeight = 288;int uSize;int iLen=avcodec_decode_video(m_pContext,m_pFrame,&uSize,pInBuffer,iBufferSize);if((uSize>0) &&(iLen>0)){LPBYTE PtrY = m_pFrame->data[0];LPBYTE PtrU = m_pFrame->data[1];LPBYTE PtrV = m_pFrame->data[2];int iSizeY = m_pFrame->linesize[0];int iSizeU = m_pFrame->linesize[1];int iSizeV = m_pFrame->linesize[2];FILE*fp = fopen("1.yuv","ab");if (fp!=NULL){//copy yfor (int i =0;i<nHeight;i++){fwrite(PtrY,1,nWidth,fp);PtrY+=iSizeY;}//copy ufor (int i =0;i<nHeight/2;i++){fwrite(PtrU,1,nWidth/2,fp);PtrU+=iSizeU;}//copy vfor (int i =0;i<nHeight/2;i++){fwrite(PtrV,1,nWidth/2,fp);PtrV+=iSizeV;}////copy to filefclose(fp);}}