能ffmpeg 的请进！

会ffmpeg 的请进！！
本帖最后由 zhuweigangzwg 于 2012-02-17 16:32:09 编辑

while(av_read_frame(pDlg->pFormatCtx, &pDlg->packet) >= 0) 
{
// Is this a packet from the video stream?
if(pDlg->packet.stream_index == pDlg->videoStream) 
{
// Decode video frame
avcodec_decode_video(pDlg->pCodecCtx, pDlg->pFrame, &pDlg->frameFinished,
pDlg->packet.data, pDlg->packet.size);

// Did we get a video frame?
if(pDlg->frameFinished) 
{
AVPicture pict;

// Convert the image from its native format to RGB

struct SwsContext *img_convert_ctx;
img_convert_ctx = sws_getContext(pDlg->pCodecCtx->width,pDlg->pCodecCtx->height, pDlg->pCodecCtx->pix_fmt,
pDlg->pCodecCtx->width,pDlg->pCodecCtx->height,PIX_FMT_YUVJ420P,SWS_BICUBIC, NULL,NULL,NULL);      
if(img_convert_ctx == NULL)
{
fprintf(stderr, "Cannot initialize the conversion context!\n");
getchar();
}

// 将图片转换为RGB格式
sws_scale(img_convert_ctx,pDlg->pFrame->data,pDlg->pFrame->linesize,0,
pDlg->pCodecCtx->height,pict.data,pict.linesize);

//pDlg->ShowVido(RGBbuf);

Sleep(50);
}
}
// Free the packet that was allocated by av_read_frame
av_free_packet(&pDlg->packet);
}