Read h264 RTP stream with libvlc and process it with OpenCV

Hi everybody ! I want to read stream from ipCamera in h264 1920*1072 and process it using Opencv. I tried the easy way with videoCapture("rtp://myadress") but the image is very bad and i have error like : "error while decoding : MB...". So I want to use libVlc to read the stream and access the data with openCV. I find this post and I use his code : http://answers.opencv.org/question/56000/open-mp4-with-libvlc-and-opencv-c/ I change the size of the data for matching mine 1920*1072. But I don't really understand this code. But i have always the same console logs : - [rawvideo @ 0x7fe04c2cd440] AVFrame.format is not set - [rawvideo @ 0x7fe04c2cd440]AVFrame.width or height is not set - MediaPlayerPositionChanged - MediaPlayerTimeChanged 0 ms And i have in my file log: - rtp debug: ignoring late packet (sequence: 27130) - rtp debug: ignoring late packet (sequence: 27131) - packetizer_h264 warning: waiting for SPS/PPS - rtp debug: ignoring late packet (sequence: 27132) and no image is shown.

using namespace cv;
    using namespace std;
    struct VideoDataStruct {
      int param;
    };
    int done = 0;
    libvlc_media_player_t *mp;
    unsigned int videoBufferSize = 0;
    uint8_t *videoBuffer = 0;
     void cbVideoPrerender(void *p_video_data, uint8_t **pp_pixel_buffer, int size) {
    // Locking
      if (size > videoBufferSize || !videoBuffer)
      {
        printf("Reallocate raw video buffer\n");
        free(videoBuffer);
        videoBuffer = (uint8_t *) malloc(size);
        videoBufferSize = size;
      }
       *pp_pixel_buffer = videoBuffer;
    }
     void cbVideoPostrender(void *p_video_data, uint8_t *p_pixel_buffer, int width, int height, int pixel_pitch, int size, int64_t pts) {
         // Unlocking
         //CloseHandle(hMutex);
     }
     static void handleEvent(const libvlc_event_t* pEvt, void* pUserData) {
       libvlc_time_t time;
       switch(pEvt->type)
       {
          case libvlc_MediaPlayerTimeChanged:
              time = libvlc_media_player_get_time(mp);
              printf("MediaPlayerTimeChanged %lld ms\n", (long long)time);
              break;
          case libvlc_MediaPlayerEndReached:
              printf ("MediaPlayerEndReached\n");
              done = 1;
            break;
           default:
              printf("%s\n", libvlc_event_type_name(pEvt->type));
        }
    }
    int main(int argc, char* argv[]) {
    // VLC pointers
    libvlc_instance_t *inst;
    libvlc_media_t *m;
    void *pUserData = 0;
    VideoDataStruct dataStruct;
    // VLC options
    char smem_options[1000];
    // RV24
    sprintf(smem_options
        , "#transcode{vcodec=RV24}:smem{"
         "video-prerender-callback=%lld,"
         "video-postrender-callback=%lld,"
         "video-data=%lld,"
         "no-time-sync},"
        , (long long int)(intptr_t)(void*)&cbVideoPrerender
        , (long long int)(intptr_t)(void*)&cbVideoPostrender
        , (long long int)(intptr_t)(void*)&dataStruct
    );
    const char * const vlc_args[] = {
              "-I", "dummy",            // Don't use any interface
              "--ignore-config",        // Don't use VLC's config
              "--extraintf=logger",     // Log anything
              "--verbose=2",            // Be verbose
              "--sout", smem_options    // Stream to memory
               };
    // We launch VLC
    inst = libvlc_new(sizeof(vlc_args) / sizeof(vlc_args[0]), vlc_args);
    /* Create a new item */
    //m = libvlc_media_new_path(inst, "outputDiff.avi");
        m= libvlc_media_new_location(inst, "rtp://myadress:myport");
    /* Create a media player playing environement */
    mp = libvlc_media_player_new_from_media (m);
    libvlc_event_manager_t* eventManager = libvlc_media_player_event_manager(mp);
    libvlc_event_attach(eventManager, libvlc_MediaPlayerTimeChanged, handleEvent, pUserData);
    libvlc_event_attach(eventManager, libvlc_MediaPlayerEndReached, handleEvent, pUserData);
    libvlc_event_attach(eventManager, libvlc_MediaPlayerPositionChanged, handleEvent, pUserData);
    libvlc_video_set_format(mp, "RV24", VIDEOWIDTH, VIDEOHEIGHT, VIDEOWIDTH* 3 );
    /* play the media_player */
    libvlc_media_player_play (mp);
     while(1)
     {
         if(videoBuffer)            // Check for invalid input
         {
             // CV_8UC3 = 8 bits, 3 chanels
             Mat img = Mat(Size(VIDEOWIDTH, VIDEOHEIGHT), CV_8UC3, videoBuffer);
             cvtColor(img, img, CV_RGB2BGR);
             namedWindow("Display window", WINDOW_AUTOSIZE);    // Create a window for display.
             imshow("Display window", img);     // Show our image inside it.
         }
     }
     libvlc_release (inst);
    }
Thank you guys.
Bye