func: static int tb_unreliable(AVCodecContext *c)
  
  {
  
      if (c->time_base.den >= 101L * c->time_base.num ||
  
          c->time_base.den <    5L * c->time_base.num ||
  
          // c->codec_tag == AV_RL32("DIVX") ||
  
          // c->codec_tag == AV_RL32("XVID") ||
  
          c->codec_id == AV_CODEC_ID_MPEG2VIDEO ||
  
          c->codec_id == AV_CODEC_ID_H264)
  
          return 1;
  
      return 0;
  
  }
  