[Ffmpeg-devel] Bad image with H.263

[Cool_Zer0]

Hi there!

I'm having some problems decoding H.263.
Here's the situation:

I'm receiving the H.263 frame on a RTP packets. I can extract the H.263
packet from the RTP Packet.
After that I send the full H.263 packet to ffmpeg with something like:

{
...
video_decode((unsigned char*)payload, payloadlen);
...
}

At the end I put the code that I use to handle video...
The problem is that the image looks very strange (I can't explain in in
English...)... I've upload to a server two things:

- Print screen of image problems:
http://student.dei.uc.pt/~ncenteio/ffmpeg/raw_images.bmp (890kb)
- RAW format in RGB24 of the images in
http://student.dei.uc.pt/~ncenteio/ffmpeg/raw.zip (4Mb)


I appreciate any help that you can give me.



Thanks



---------------------------

AVCodec *codec;
AVCodecContext *c = NULL;
int frame, size, got_picture, len;
AVFrame *picture;
uint8_t inbuf[INBUF_SIZE + FF_INPUT_BUFFER_PADDING_SIZE], *inbuf_ptr;
char buf[1024];
AVFrame *pFrameRGB;
int     numBytes;
uint8_t *buffer;

void video_decode_init() {

    /* must be called before using avcodec lib */
    avcodec_init();

    /* register all the codecs (you can also register only the codec
       you wish to have smaller code */
    register_avcodec(&h263_decoder);
    av_register_codec_parser(&h263_parser);   


    // Allocate an AVFrame structure
    pFrameRGB=avcodec_alloc_frame();
    if(pFrameRGB==NULL) {
        printf("Error no avcodec_alloc_frame do RGB!!!\n");
        exit(1);
    }

    // Determine required buffer size and allocate buffer
    numBytes=avpicture_get_size(PIX_FMT_RGB24, 176, 144);
    buffer=new uint8_t[numBytes];

    // Assign appropriate parts of buffer to image planes in pFrameRGB
    avpicture_fill((AVPicture *)pFrameRGB, buffer, PIX_FMT_RGB24, 176, 144);


    /* 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);

    printf("Video decoding\n");

    /* find the mpeg1 video decoder */
    codec = avcodec_find_decoder(CODEC_ID_H263);
    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 dont send complete frames */

    /* for some codecs, such as msmpeg4 and mpeg4, width and height
       MUST be initialized there because these info are not available
       in the bitstream */
    //c->width=176;
    //c->height=144;

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

    img_convert_create(); // I need this because the initialization of
the array doesn't work in Microsoft Visual C++ Compiler
    frame = 0;

}

void video_decode_terminate() {

    avcodec_close(c);
    av_free(c);
    av_free(picture);

}

void video_decode(unsigned char* payload, int payloadsize)
{

    //dump_frame_header(payload, frame);

    inbuf_ptr = payload;
    size = payloadsize;
    while (size > 0) {
        len = avcodec_decode_video(c, picture, &got_picture, inbuf_ptr,
size);

        if (len < 0) {
            return;
        }
        if (got_picture) {
            img_convert((AVPicture *)pFrameRGB, PIX_FMT_RGB24,
(AVPicture*)picture, c->pix_fmt, 176, 144);
            rgb_save(pFrameRGB->data[0], "frame");
            frame++;
        }
        size -= len;
        inbuf_ptr += len;       
    }

    len = avcodec_decode_video(c, picture, &got_picture, NULL, 0);
    if (got_picture) {
        img_convert((AVPicture *)pFrameRGB, PIX_FMT_RGB24,
(AVPicture*)picture, c->pix_fmt, 176, 144);      
        rgb_save(pFrameRGB->data[0], "frame");
        frame++;
    }

}

void rgb_save(unsigned char *buf, char *filename)
{
    static int frame_nbr = 0;
    char file[200];
    sprintf(file, "0%d_frame.raw", (frame_nbr++));

    FILE *f;
 
    f=fopen(file,"wb");
    fwrite(buf, 1, 176*144*3, f);   
    fclose(file);

}