git.sesse.net Git - ffmpeg/blob - libavformat/subviewer1dec.c

   1 /*
   2  * Copyright (c) 2012 Clément Bœsch
   3  *
   4  * This file is part of FFmpeg.
   5  *
   6  * FFmpeg is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * FFmpeg is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with FFmpeg; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 /**
  22  * @file
  23  * SubViewer v1 subtitle demuxer
  24  */
  25
  26 #include "avformat.h"
  27 #include "internal.h"
  28 #include "subtitles.h"
  29
  30 typedef struct {
  31     FFDemuxSubtitlesQueue q;
  32 } SubViewer1Context;
  33
  34 static int subviewer1_probe(const AVProbeData *p)
  35 {
  36     const unsigned char *ptr = p->buf;
  37
  38     if (strstr(ptr, "******** START SCRIPT ********"))
  39         return AVPROBE_SCORE_EXTENSION;
  40     return 0;
  41 }
  42
  43 static int subviewer1_read_header(AVFormatContext *s)
  44 {
  45     int delay = 0;
  46     AVPacket *sub = NULL;
  47     SubViewer1Context *subviewer1 = s->priv_data;
  48     AVStream *st = avformat_new_stream(s, NULL);
  49
  50     if (!st)
  51         return AVERROR(ENOMEM);
  52     avpriv_set_pts_info(st, 64, 1, 1);
  53     st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;
  54     st->codecpar->codec_id   = AV_CODEC_ID_SUBVIEWER1;
  55
  56     while (!avio_feof(s->pb)) {
  57         char line[4096];
  58         int len = ff_get_line(s->pb, line, sizeof(line));
  59         int hh, mm, ss;
  60
  61         if (!len)
  62             break;
  63
  64         if (!strncmp(line, "[DELAY]", 7)) {
  65             ff_get_line(s->pb, line, sizeof(line));
  66             sscanf(line, "%d", &delay);
  67         }
  68
  69         if (sscanf(line, "[%d:%d:%d]", &hh, &mm, &ss) == 3) {
  70             const int64_t pos = avio_tell(s->pb);
  71             int64_t pts_start = hh*3600LL + mm*60LL + ss + delay;
  72
  73             len = ff_get_line(s->pb, line, sizeof(line));
  74             line[strcspn(line, "\r\n")] = 0;
  75             if (!*line) {
  76                 if (sub)
  77                     sub->duration = pts_start - sub->pts;
  78             } else {
  79                 sub = ff_subtitles_queue_insert(&subviewer1->q, line, len, 0);
  80                 if (!sub) {
  81                     ff_subtitles_queue_clean(&subviewer1->q);
  82                     return AVERROR(ENOMEM);
  83                 }
  84                 sub->pos = pos;
  85                 sub->pts = pts_start;
  86                 sub->duration = -1;
  87             }
  88         }
  89     }
  90
  91     ff_subtitles_queue_finalize(s, &subviewer1->q);
  92     return 0;
  93 }
  94
  95 static int subviewer1_read_packet(AVFormatContext *s, AVPacket *pkt)
  96 {
  97     SubViewer1Context *subviewer1 = s->priv_data;
  98     return ff_subtitles_queue_read_packet(&subviewer1->q, pkt);
  99 }
 100
 101 static int subviewer1_read_seek(AVFormatContext *s, int stream_index,
 102                                int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
 103 {
 104     SubViewer1Context *subviewer1 = s->priv_data;
 105     return ff_subtitles_queue_seek(&subviewer1->q, s, stream_index,
 106                                    min_ts, ts, max_ts, flags);
 107 }
 108
 109 static int subviewer1_read_close(AVFormatContext *s)
 110 {
 111     SubViewer1Context *subviewer1 = s->priv_data;
 112     ff_subtitles_queue_clean(&subviewer1->q);
 113     return 0;
 114 }
 115
 116 const AVInputFormat ff_subviewer1_demuxer = {
 117     .name           = "subviewer1",
 118     .long_name      = NULL_IF_CONFIG_SMALL("SubViewer v1 subtitle format"),
 119     .priv_data_size = sizeof(SubViewer1Context),
 120     .read_probe     = subviewer1_probe,
 121     .read_header    = subviewer1_read_header,
 122     .read_packet    = subviewer1_read_packet,
 123     .read_seek2     = subviewer1_read_seek,
 124     .read_close     = subviewer1_read_close,
 125     .extensions     = "sub",
 126 };