func: static int parse_chunks(AVFormatContext *s, int mode, int64_t seekts, int *len_ptr)
  
  {
  
      WtvContext *wtv = s->priv_data;
  
      AVIOContext *pb = wtv->pb;
  
      while (!url_feof(pb)) {
  
          ff_asf_guid g;
  
          int len, sid, consumed;
  
  
  
          ff_get_guid(pb, &g);
  
          len = avio_rl32(pb);
  
          if (len < 32)
  
              break;
  
          sid = avio_rl32(pb) & 0x7FFF;
  
          avio_skip(pb, 8);
  
          consumed = 32;
  
  
  
          if (!ff_guidcmp(g, ff_SBE2_STREAM_DESC_EVENT)) {
  
              if (ff_find_stream_index(s, sid) < 0) {
  
                  ff_asf_guid mediatype, subtype, formattype;
  
                  int size;
  
                  avio_skip(pb, 28);
  
                  ff_get_guid(pb, &mediatype);
  
                  ff_get_guid(pb, &subtype);
  
                  avio_skip(pb, 12);
  
                  ff_get_guid(pb, &formattype);
  
                  size = avio_rl32(pb);
  
                  parse_media_type(s, 0, sid, mediatype, subtype, formattype, size);
  
                  consumed += 92 + size;
  
              }
  
          } else if (!ff_guidcmp(g, ff_stream2_guid)) {
  
              int stream_index = ff_find_stream_index(s, sid);
  
              if (stream_index >= 0 && !((WtvStream*)s->streams[stream_index]->priv_data)->seen_data) {
  
                  ff_asf_guid mediatype, subtype, formattype;
  
                  int size;
  
                  avio_skip(pb, 12);
  
                  ff_get_guid(pb, &mediatype);
  
                  ff_get_guid(pb, &subtype);
  
                  avio_skip(pb, 12);
  
                  ff_get_guid(pb, &formattype);
  
                  size = avio_rl32(pb);
  
                  parse_media_type(s, s->streams[stream_index], sid, mediatype, subtype, formattype, size);
  
                  consumed += 76 + size;
  
              }
  
          } else if (!ff_guidcmp(g, EVENTID_AudioDescriptorSpanningEvent) ||
  
                     !ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
  
                     !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent) ||
  
                     !ff_guidcmp(g, EVENTID_StreamIDSpanningEvent) ||
  
                     !ff_guidcmp(g, EVENTID_SubtitleSpanningEvent) ||
  
                     !ff_guidcmp(g, EVENTID_TeletextSpanningEvent)) {
  
              int stream_index = ff_find_stream_index(s, sid);
  
              if (stream_index >= 0) {
  
                  AVStream *st = s->streams[stream_index];
  
                  uint8_t buf[258];
  
                  const uint8_t *pbuf = buf;
  
                  int buf_size;
  
  
  
                  avio_skip(pb, 8);
  
                  consumed += 8;
  
                  if (!ff_guidcmp(g, EVENTID_CtxADescriptorSpanningEvent) ||
  
                      !ff_guidcmp(g, EVENTID_CSDescriptorSpanningEvent)) {
  
                      avio_skip(pb, 6);
  
                      consumed += 6;
  
                  }
  
  
  
                  buf_size = FFMIN(len - consumed, sizeof(buf));
  
                  avio_read(pb, buf, buf_size);
  
                  consumed += buf_size;
  
                  ff_parse_mpeg2_descriptor(s, st, 0, &pbuf, buf + buf_size, NULL, 0, 0, NULL);
  
              }
  
          } else if (!ff_guidcmp(g, EVENTID_AudioTypeSpanningEvent)) {
  
              int stream_index = ff_find_stream_index(s, sid);
  
              if (stream_index >= 0) {
  
                  AVStream *st = s->streams[stream_index];
  
                  int audio_type;
  
                  avio_skip(pb, 8);
  
                  audio_type = avio_r8(pb);
  
                  if (audio_type == 2)
  
                      st->disposition |= AV_DISPOSITION_HEARING_IMPAIRED;
  
                  else if (audio_type == 3)
  
                      st->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED;
  
                  consumed += 9;
  
              }
  
          } else if (!ff_guidcmp(g, EVENTID_DVBScramblingControlSpanningEvent)) {
  
              int stream_index = ff_find_stream_index(s, sid);
  
              if (stream_index >= 0) {
  
                  avio_skip(pb, 12);
  
                  if (avio_rl32(pb))
  
                      av_log(s, AV_LOG_WARNING, "DVB scrambled stream detected (st:%d), decoding will likely fail\n", stream_index);
  
                  consumed += 16;
  
              }
  
          } else if (!ff_guidcmp(g, EVENTID_LanguageSpanningEvent)) {
  
              int stream_index = ff_find_stream_index(s, sid);
  
              if (stream_index >= 0) {
  
                  AVStream *st = s->streams[stream_index];
  
                  uint8_t language[4];
  
                  avio_skip(pb, 12);
  
                  avio_read(pb, language, 3);
  
                  if (language[0]) {
  
                      language[3] = 0;
  
                      av_dict_set(&st->metadata, "language", language, 0);
  
                      if (!strcmp(language, "nar") || !strcmp(language, "NAR"))
  
                          st->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED;
  
                  }
  
                  consumed += 15;
  
              }
  
          } else if (!ff_guidcmp(g, ff_timestamp_guid)) {
  
              int stream_index = ff_find_stream_index(s, sid);
  
              if (stream_index >= 0) {
  
                  avio_skip(pb, 8);
  
                  wtv->pts = avio_rl64(pb);
  
                  consumed += 16;
  
                  if (wtv->pts == -1)
  
                      wtv->pts = AV_NOPTS_VALUE;
  
                  else {
  
                      wtv->last_valid_pts = wtv->pts;
  
                      if (wtv->epoch == AV_NOPTS_VALUE || wtv->pts < wtv->epoch)
  
                          wtv->epoch = wtv->pts;
  
                  if (mode == SEEK_TO_PTS && wtv->pts >= seekts) {
  
                      avio_skip(pb, WTV_PAD8(len) - consumed);
  
                      return 0;
  
                  }
  
                  }
  
              }
  
          } else if (!ff_guidcmp(g, ff_data_guid)) {
  
              int stream_index = ff_find_stream_index(s, sid);
  
              if (mode == SEEK_TO_DATA && stream_index >= 0 && len > 32 && s->streams[stream_index]->priv_data) {
  
                  WtvStream *wst = s->streams[stream_index]->priv_data;
  
                  wst->seen_data = 1;
  
                  if (len_ptr) {
  
                      *len_ptr = len;
  
                  }
  
                  return stream_index;
  
              }
  
          } else if (!ff_guidcmp(g, /* DSATTRIB_WMDRMProtectionInfo */ (const ff_asf_guid){0x83,0x95,0x74,0x40,0x9D,0x6B,0xEC,0x4E,0xB4,0x3C,0x67,0xA1,0x80,0x1E,0x1A,0x9B})) {
  
              int stream_index = ff_find_stream_index(s, sid);
  
              if (stream_index >= 0)
  
                  av_log(s, AV_LOG_WARNING, "encrypted stream detected (st:%d), decoding will likely fail\n", stream_index);
  
          } else if (
  
              !ff_guidcmp(g, /* DSATTRIB_CAPTURE_STREAMTIME */ (const ff_asf_guid){0x14,0x56,0x1A,0x0C,0xCD,0x30,0x40,0x4F,0xBC,0xBF,0xD0,0x3E,0x52,0x30,0x62,0x07}) ||
  
              !ff_guidcmp(g, /* DSATTRIB_PBDATAG_ATTRIBUTE */ (const ff_asf_guid){0x79,0x66,0xB5,0xE0,0xB9,0x12,0xCC,0x43,0xB7,0xDF,0x57,0x8C,0xAA,0x5A,0x7B,0x63}) ||
  
              !ff_guidcmp(g, /* DSATTRIB_PicSampleSeq */ (const ff_asf_guid){0x02,0xAE,0x5B,0x2F,0x8F,0x7B,0x60,0x4F,0x82,0xD6,0xE4,0xEA,0x2F,0x1F,0x4C,0x99}) ||
  
              !ff_guidcmp(g, /* DSATTRIB_TRANSPORT_PROPERTIES */ ff_DSATTRIB_TRANSPORT_PROPERTIES) ||
  
              !ff_guidcmp(g, /* dvr_ms_vid_frame_rep_data */ (const ff_asf_guid){0xCC,0x32,0x64,0xDD,0x29,0xE2,0xDB,0x40,0x80,0xF6,0xD2,0x63,0x28,0xD2,0x76,0x1F}) ||
  
              !ff_guidcmp(g, /* EVENTID_ChannelChangeSpanningEvent */ (const ff_asf_guid){0xE5,0xC5,0x67,0x90,0x5C,0x4C,0x05,0x42,0x86,0xC8,0x7A,0xFE,0x20,0xFE,0x1E,0xFA}) ||
  
              !ff_guidcmp(g, /* EVENTID_ChannelInfoSpanningEvent */ (const ff_asf_guid){0x80,0x6D,0xF3,0x41,0x32,0x41,0xC2,0x4C,0xB1,0x21,0x01,0xA4,0x32,0x19,0xD8,0x1B}) ||
  
              !ff_guidcmp(g, /* EVENTID_ChannelTypeSpanningEvent */ (const ff_asf_guid){0x51,0x1D,0xAB,0x72,0xD2,0x87,0x9B,0x48,0xBA,0x11,0x0E,0x08,0xDC,0x21,0x02,0x43}) ||
  
              !ff_guidcmp(g, /* EVENTID_PIDListSpanningEvent */ (const ff_asf_guid){0x65,0x8F,0xFC,0x47,0xBB,0xE2,0x34,0x46,0x9C,0xEF,0xFD,0xBF,0xE6,0x26,0x1D,0x5C}) ||
  
              !ff_guidcmp(g, /* EVENTID_SignalAndServiceStatusSpanningEvent */ (const ff_asf_guid){0xCB,0xC5,0x68,0x80,0x04,0x3C,0x2B,0x49,0xB4,0x7D,0x03,0x08,0x82,0x0D,0xCE,0x51}) ||
  
              !ff_guidcmp(g, /* EVENTID_StreamTypeSpanningEvent */ (const ff_asf_guid){0xBC,0x2E,0xAF,0x82,0xA6,0x30,0x64,0x42,0xA8,0x0B,0xAD,0x2E,0x13,0x72,0xAC,0x60}) ||
  
              !ff_guidcmp(g, (const ff_asf_guid){0x1E,0xBE,0xC3,0xC5,0x43,0x92,0xDC,0x11,0x85,0xE5,0x00,0x12,0x3F,0x6F,0x73,0xB9}) ||
  
              !ff_guidcmp(g, (const ff_asf_guid){0x3B,0x86,0xA2,0xB1,0xEB,0x1E,0xC3,0x44,0x8C,0x88,0x1C,0xA3,0xFF,0xE3,0xE7,0x6A}) ||
  
              !ff_guidcmp(g, (const ff_asf_guid){0x4E,0x7F,0x4C,0x5B,0xC4,0xD0,0x38,0x4B,0xA8,0x3E,0x21,0x7F,0x7B,0xBF,0x52,0xE7}) ||
  
              !ff_guidcmp(g, (const ff_asf_guid){0x63,0x36,0xEB,0xFE,0xA1,0x7E,0xD9,0x11,0x83,0x08,0x00,0x07,0xE9,0x5E,0xAD,0x8D}) ||
  
              !ff_guidcmp(g, (const ff_asf_guid){0x70,0xE9,0xF1,0xF8,0x89,0xA4,0x4C,0x4D,0x83,0x73,0xB8,0x12,0xE0,0xD5,0xF8,0x1E}) ||
  
              !ff_guidcmp(g, ff_index_guid) ||
  
              !ff_guidcmp(g, ff_sync_guid) ||
  
              !ff_guidcmp(g, ff_stream1_guid) ||
  
              !ff_guidcmp(g, (const ff_asf_guid){0xF7,0x10,0x02,0xB9,0xEE,0x7C,0xED,0x4E,0xBD,0x7F,0x05,0x40,0x35,0x86,0x18,0xA1})) {
  
              //ignore known guids
  
          } else
  
              av_log(s, AV_LOG_WARNING, "unsupported chunk:"FF_PRI_GUID"\n", FF_ARG_GUID(g));
  
  
  
          avio_skip(pb, WTV_PAD8(len) - consumed);
  
      }
  
      return AVERROR_EOF;
  
  }
  