func: int ff_wms_parse_sdp_a_line(AVFormatContext *s, const char *p)
  
  {
  
      int ret = 0;
  
      if (av_strstart(p, "pgmpu:data:application/vnd.ms.wms-hdr.asfv1;base64,", &p)) {
  
          AVIOContext pb;
  
          RTSPState *rt = s->priv_data;
  
          AVDictionary *opts = NULL;
  
          int len = strlen(p) * 6 / 8;
  
          char *buf = av_mallocz(len);
  
          AVInputFormat *iformat;
  
  
  
          if (!buf)
  
              return AVERROR(ENOMEM);
  
          av_base64_decode(buf, p, len);
  
  
  
          if (rtp_asf_fix_header(buf, len) < 0)
  
              av_log(s, AV_LOG_ERROR,
  
                     "Failed to fix invalid RTSP-MS/ASF min_pktsize\n");
  
          init_packetizer(&pb, buf, len);
  
          if (rt->asf_ctx) {
  
              avformat_close_input(&rt->asf_ctx);
  
          }
  
  
  
          if (!(iformat = av_find_input_format("asf")))
  
              return AVERROR_DEMUXER_NOT_FOUND;
  
  
  
          rt->asf_ctx = avformat_alloc_context();
  
          if (!rt->asf_ctx) {
  
              av_free(buf);
  
              return AVERROR(ENOMEM);
  
          }
  
          rt->asf_ctx->pb      = &pb;
  
          av_dict_set(&opts, "no_resync_search", "1", 0);
  
  
  
          if ((ret = ff_copy_whiteblacklists(rt->asf_ctx, s)) < 0) {
  
              av_dict_free(&opts);
  
              return ret;
  
          }
  
  
  
          ret = avformat_open_input(&rt->asf_ctx, "", iformat, &opts);
  
          av_dict_free(&opts);
  
          if (ret < 0) {
  
              av_free(buf);
  
              return ret;
  
          }
  
          av_dict_copy(&s->metadata, rt->asf_ctx->metadata, 0);
  
          rt->asf_pb_pos = avio_tell(&pb);
  
          av_free(buf);
  
          rt->asf_ctx->pb = NULL;
  
      }
  
      return ret;
  
  }
  