text: /*
   * Copyright (c) 2012 Clément Bœsch
   *
   * This file is part of FFmpeg.
   *
   * FFmpeg is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * FFmpeg is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with FFmpeg; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
   */
  
  /**
   * @file
   * MPlayer subtitles format demuxer
   */
  
  #include "avformat.h"
  #include "internal.h"
  #include "subtitles.h"
  
  typedef struct {
      FFDemuxSubtitlesQueue q;
  } MPSubContext;
  
  static int mpsub_probe(AVProbeData *p)
  {
      const char *ptr     = p->buf;
      const char *ptr_end = p->buf + p->buf_size;
  
      while (ptr < ptr_end) {
          if (!memcmp(ptr, "FORMAT=TIME", 11))
              return AVPROBE_SCORE_EXTENSION;
          if (!memcmp(ptr, "FORMAT=", 7))
              return AVPROBE_SCORE_EXTENSION / 3;
          ptr += strcspn(ptr, "\n") + 1;
      }
      return 0;
  }
  
  static int mpsub_read_header(AVFormatContext *s)
  {
      MPSubContext *mpsub = s->priv_data;
      AVStream *st;
      AVBPrint buf;
      AVRational pts_info = (AVRational){ 100, 1 }; // ts based by default
      int res = 0;
      float multiplier = 100.0;
      float current_pts = 0;
  
      av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED);
  
      while (!url_feof(s->pb)) {
          char line[1024];
          float start, duration;
          int fps, len = ff_get_line(s->pb, line, sizeof(line));
  
          if (!len)
              break;
  
          line[strcspn(line, "\r\n")] = 0;
  
          if (sscanf(line, "FORMAT=%d", &fps) == 1 && fps > 3 && fps < 100) {
              /* frame based timing */
              pts_info = (AVRational){ fps, 1 };
              multiplier = 1.0;
          } else if (sscanf(line, "%f %f", &start, &duration) == 2) {
              AVPacket *sub;
              const int64_t pos = avio_tell(s->pb);
  
              ff_subtitles_read_chunk(s->pb, &buf);
              if (buf.len) {
                  sub = ff_subtitles_queue_insert(&mpsub->q, buf.str, buf.len, 0);
                  if (!sub) {
                      res = AVERROR(ENOMEM);
                      goto end;
                  }
                  sub->pts = (int64_t)(current_pts + start*multiplier);
                  sub->duration = (int)(duration * multiplier);
                  current_pts += (start + duration) * multiplier;
                  sub->pos = pos;
              }
          }
      }
  
      st = avformat_new_stream(s, NULL);
      if (!st)
          return AVERROR(ENOMEM);
      avpriv_set_pts_info(st, 64, pts_info.den, pts_info.num);
      st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
      st->codec->codec_id   = AV_CODEC_ID_TEXT;
  
      ff_subtitles_queue_finalize(&mpsub->q);
  
  end:
      av_bprint_finalize(&buf, NULL);
      return res;
  }
  
  static int mpsub_read_packet(AVFormatContext *s, AVPacket *pkt)
  {
      MPSubContext *mpsub = s->priv_data;
      return ff_subtitles_queue_read_packet(&mpsub->q, pkt);
  }
  
  static int mpsub_read_seek(AVFormatContext *s, int stream_index,
                             int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
  {
      MPSubContext *mpsub = s->priv_data;
      return ff_subtitles_queue_seek(&mpsub->q, s, stream_index,
                                     min_ts, ts, max_ts, flags);
  }
  
  static int mpsub_read_close(AVFormatContext *s)
  {
      MPSubContext *mpsub = s->priv_data;
      ff_subtitles_queue_clean(&mpsub->q);
      return 0;
  }
  
  AVInputFormat ff_mpsub_demuxer = {
      .name           = "mpsub",
      .long_name      = NULL_IF_CONFIG_SMALL("MPlayer subtitles"),
      .priv_data_size = sizeof(MPSubContext),
      .read_probe     = mpsub_probe,
      .read_header    = mpsub_read_header,
      .read_packet    = mpsub_read_packet,
      .read_seek2     = mpsub_read_seek,
      .read_close     = mpsub_read_close,
      .extensions     = "sub",
  };
  