Lars Blumberg <Lars.Blumberg <at> aquasoft.de> writes:

...

Thanks Martin, that helps a lot to test my code! Best regards Lars "Martin Boehme" <boehme <at> inb.uni-luebeck.de> schrieb im Newsbeitrag news:4378513F.2070904 <at> inb.uni-luebeck.de... Hi Lars, I want to use the libavcodec/libavformat DLLs to encode a video/sound stream. Therefore I want to put every single frame into the stream. Is there any place where I can find some information about how to do that, may be a sample application, tutorial or something like that? I am programming with Delphi, but I guess als VC++ or VB code would be helpfull. I want to load the DLLs dynamically into the application. Thanks for any comments. Try output_example.c (included in the FFmpeg distribution). That's a pretty accessible example of how to output video and audio streams. Martin

Has anyone been able to successfully use libavcodec dll in a VC++ program? I tried doing this by creating a Dialog based applicatio, dynamically linking and then mashing/modifying the code given in apiexample.c and output_example.c I now have a workable code that encodes a 12Mb file to a 100kb MPEG video file but this file doesnt even play on WindMediaPLayer. I dont think I am encoding the entire file/ all the frames so any help will be greatly appreciated. Am posting the code that I have written so far void Cfflib4Dlg::pgmsave(unsigned char *buf,int wrap, int xsize,int ysize,char *filename) { FILE *f2; int i; f2=fopen("C:/test.mpeg","w"); if(!f2){ CString str; int a = GetLastError(); str.Format("%d",a); AfxMessageBox(str); AfxMessageBox("file"); } fprintf(f2,"P5\n%d %d\n%d\n",xsize,ysize,255); for(i=0;i<ysize;i++) fwrite(buf + i * wrap,1,xsize,f2); fclose(f2); } void Cfflib4Dlg::OnBnClickedOk() { // int frame, sized, got_picture, len,outbuf_size; uint8_t inbuf[INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE], *inbuf_ptr; char buf[1024]; /* set end of buffer to 0 (this ensures that no overreading happens for damaged mpeg streams) */ memset(inbuf + INBUF_SIZE, 0, FF_INPUT_BUFFER_PADDING_SIZE); int i, out_size, size, x, y, outbuf_size,len,got_picture,frame; FILE *f; uint8_t *outbuf, *picture_buf; HMODULE hDll = LoadLibrary("avcodec.dll"); if(hDll== NULL) { CString str; int a = GetLastError(); str.Format("%d",a); AfxMessageBox(str); AfxMessageBox("first"); AfxMessageBox("Failed loading1"); } typedef void (avcodec_init)(); avcodec_init* p = (avcodec_init*)GetProcAddress(hDll, "avcodec_init"); if(p==NULL) AfxMessageBox("Failed loading2"); p(); typedef void (avcodec_register_all)(); avcodec_register_all* p1a = (avcodec_register_all*)GetProcAddress(hDll, "avcodec_register_all"); if(p1a==NULL) AfxMessageBox("Failed loading3"); p1a(); typedef AVCodec * (avcodec_find_encoder)(int CODECID); avcodec_find_encoder* p3 = (avcodec_find_encoder*)GetProcAddress(hDll, "avcodec_find_encoder"); if(p3==NULL) AfxMessageBox("Failed loading3"); p3(CODEC_ID_MPEG1VIDEO); AVCodec *codec=p3(CODEC_ID_MPEG1VIDEO); typedef AVCodecContext* (avcodec_alloc_context)(); avcodec_alloc_context* p4 = (avcodec_alloc_context*)GetProcAddress(hDll, "avcodec_alloc_context"); if(p4==NULL) AfxMessageBox("Failed loading4"); p4(); AVCodecContext *avctx = p4(); typedef AVFrame* (avcodec_alloc_frame)(); avcodec_alloc_frame* p7 =(avcodec_alloc_frame*)GetProcAddress(hDll,"avcodec_alloc_frame"); p7(); AVFrame *picture =p7(); avctx->width = 352; avctx->height = 288; avctx->frame_rate = 25; typedef int (avcodec_open)(AVCodecContext *avctx, AVCodec *codec); avcodec_open* p2 = (avcodec_open*)GetProcAddress(hDll, "avcodec_open"); if(p2==NULL) AfxMessageBox("Failed loading2"); p2(avctx,codec); typedef int (avcodec_encode_video)(AVCodecContext *avctx, uint8_t *buf, int buf_size, const AVFrame *pict); avcodec_encode_video *p9=(avcodec_encode_video*)GetProcAddress(hDll, "avcodec_encode_video"); if(p9==NULL) AfxMessageBox("Failed loading9"); typedef int (avcodec_close)(AVCodecContext *avctx); avcodec_close *p10=(avcodec_close*)GetProcAddress(hDll, "avcodec_close"); if(p10==NULL) AfxMessageBox("Failed loading9"); f=fopen("C:/Rahul.avi","r"); if(!f){ CString str; int a = GetLastError(); str.Format("%d",a); AfxMessageBox(str); AfxMessageBox("file"); } outbuf_size = 100000; outbuf = (uint8_t*)malloc(outbuf_size); size = avctx->width * avctx->height; picture_buf = (uint8_t*)malloc((size * 3) / 2); /* size for YUV 420 */ picture->data[0] = picture_buf; picture->data[1] = picture->data[0] + size; picture->data[2] = picture->data[1] + size / 4; picture->linesize[0] = avctx->width; picture->linesize[1] = avctx->width / 2; picture->linesize[2] = avctx->width / 2; frame = 0; for(;;) { size = fread(inbuf, 1, INBUF_SIZE, f); if (size == 0) break; inbuf_ptr = inbuf; while (size > 0) { len = p9(avctx,outbuf, outbuf_size, picture); if (len < 0) { //fprintf(stderr, "Error while decoding frame %d\n", frame); //("error while encoding"); exit(1); } else { //printf("saving frame %3d\n", frame); fflush(stdout); _snprintf(buf, sizeof(buf),"C:\test.mpeg",frame); //buf +=sprintf(buf,frame); pgmsave(picture->data[0], picture->linesize[0], avctx->width, avctx->height, buf); frame++; } size -= len; inbuf_ptr += len; } } len = p9(avctx,outbuf, outbuf_size, picture); // if (got_picture) { // printf("saving last frame %3d\n", frame); fflush(stdout); /* the picture is allocated by the decoder. no need to free it */ _snprintf(buf, sizeof(buf),"C:\test.mpeg",frame); pgmsave(picture->data[0], picture->linesize[0], avctx->width, avctx->height, buf); frame++; // } outbuf[0] = 0x00; outbuf[1] = 0x00; outbuf[2] = 0x01; outbuf[3] = 0xb7; FILE *f2; // int i; f2=fopen("C:/test.mpeg","a+"); fwrite(outbuf,1,4,f2); fclose(f); fclose(f2); p10(avctx); // TODO: Add your control notification handler code here FreeLibrary(hDll); OnOK(); }