void video_decode_example const char outfilename const char filename A

void video_decode_example(const char *outfilename, const char *filename)
{
    AVCodec *codec;
    AVCodecContext *c = NULL;
    int frame, size, got_picture, len;
    FILE *f;
    AVFrame *picture;
    uint8_t inbuf[INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE], *inbuf_ptr;
    char buf[1024];
    memset(inbuf + INBUF_SIZE, 0, FF_INPUT_BUFFER_PADDING_SIZE);
    printf("Video = decoding\n");

    codec = avcodec_find_decoder(CODEC_ID_MPEG1VIDEO);
    if (!codec)
    {
        fprintf(stderr, "codec not found\n"); exit(1);
    }

    c = avcodec_alloc_context();
    picture = avcodec_alloc_frame();
    if(codec->capabilities&CODEC_CAP_TRUNCATED)
        c->flags|= CODEC_FLAG_TRUNCATED; /* we do not send complete frames */

    /* For some codecs, such as msmpeg4 and mpeg4, width and height
       MUST be initialized there because this information is not
       available in the bitstream. */

    /* open it */

    if (avcodec_open(c, codec) < 0) {
        fprintf(stderr, "could not open codec\n");
        exit(1);
    }

    /* the codec gives us the frame size, in samples */

    f = fopen(filename, "rb");
    if (!f) {
        fprintf(stderr, "could not open %s\n", filename);
        exit(1);
    }
    frame = 0;
    for(;;)
    {
        size = fread(inbuf, 1, INBUF_SIZE, f);
        if (size == 0)
            break;

        inbuf_ptr = inbuf;
        while (size > 0) {
            len = avcodec_decode_video(c, picture, &got_picture,
                                       inbuf_ptr, size);
            if (len < 0) {
                fprintf(stderr, "Error while decoding frame %d\n", frame);
                exit(1);
            }
            if (got_picture) {
                printf("saving frame %3d\n", frame);
                fflush(stdout);

                //snprintf(buf, sizeof(buf), outfilename, frame);
                SaveFrame(picture, c->width, c->height, frame); 
                frame++;
                break;

            }
            size -= len;
            inbuf_ptr += len;
        }
    }
    /* some codecs, such as MPEG, transmit the I and P frame with a
       latency of one frame. You must do the following to have a
       chance to get the last frame of the video */
    len = avcodec_decode_video(c, picture, &got_picture,
                               NULL, 0);
    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), outfilename, frame);
        return pgm_save(picture->data[0], picture->linesize[0],
                 c->width, c->height, buf);
        frame++;
    }

    fclose(f);

    avcodec_close(c);
    av_free(c);
    av_free(picture);
    printf("\n");
}