func: static int srt_decode_frame(AVCodecContext *avctx,
  
                              void *data, int *got_sub_ptr, AVPacket *avpkt)
  
  {
  
      AVSubtitle *sub = data;
  
      AVBPrint buffer;
  
      int x1 = -1, y1 = -1, x2 = -1, y2 = -1;
  
      int size, ret;
  
      const uint8_t *p = av_packet_get_side_data(avpkt, AV_PKT_DATA_SUBTITLE_POSITION, &size);
  
      FFASSDecoderContext *s = avctx->priv_data;
  
  
  
      if (p && size == 16) {
  
          x1 = AV_RL32(p     );
  
          y1 = AV_RL32(p +  4);
  
          x2 = AV_RL32(p +  8);
  
          y2 = AV_RL32(p + 12);
  
      }
  
  
  
      if (avpkt->size <= 0)
  
          return avpkt->size;
  
  
  
      av_bprint_init(&buffer, 0, AV_BPRINT_SIZE_UNLIMITED);
  
  
  
      srt_to_ass(avctx, &buffer, avpkt->data, x1, y1, x2, y2);
  
      ret = ff_ass_add_rect(sub, buffer.str, s->readorder++, 0, NULL, NULL);
  
      av_bprint_finalize(&buffer, NULL);
  
      if (ret < 0)
  
          return ret;
  
  
  
      *got_sub_ptr = sub->num_rects > 0;
  
      return avpkt->size;
  
  }
  