1/*
2 * Copyright (c) 2012 Cl��ment B��sch
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 * AQTitle subtitles format demuxer
24 *
25 * @see http://web.archive.org/web/20070210095721/http://www.volny.cz/aberka/czech/aqt.html
26 * @see https://trac.annodex.net/wiki/AQTitle
27 */
28
29#include "avformat.h"
30#include "internal.h"
31#include "subtitles.h"
32#include "libavutil/opt.h"
33
34typedef struct {
35    const AVClass *class;
36    FFDemuxSubtitlesQueue q;
37    AVRational frame_rate;
38} AQTitleContext;
39
40static int aqt_probe(AVProbeData *p)
41{
42    int frame;
43    const char *ptr = p->buf;
44
45    if (sscanf(ptr, "-->> %d", &frame) == 1)
46        return AVPROBE_SCORE_EXTENSION;
47    return 0;
48}
49
50static int aqt_read_header(AVFormatContext *s)
51{
52    AQTitleContext *aqt = s->priv_data;
53    AVStream *st = avformat_new_stream(s, NULL);
54    int new_event = 1;
55    int64_t pos = 0, frame = AV_NOPTS_VALUE;
56    AVPacket *sub = NULL;
57
58    if (!st)
59        return AVERROR(ENOMEM);
60    avpriv_set_pts_info(st, 64, aqt->frame_rate.den, aqt->frame_rate.num);
61    st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
62    st->codec->codec_id   = AV_CODEC_ID_TEXT;
63
64    while (!url_feof(s->pb)) {
65        char line[4096];
66        int len = ff_get_line(s->pb, line, sizeof(line));
67
68        if (!len)
69            break;
70
71        line[strcspn(line, "\r\n")] = 0;
72
73        if (sscanf(line, "-->> %"SCNd64, &frame) == 1) {
74            new_event = 1;
75            pos = avio_tell(s->pb);
76            if (sub) {
77                sub->duration = frame - sub->pts;
78                sub = NULL;
79            }
80        } else if (*line) {
81            if (!new_event) {
82                sub = ff_subtitles_queue_insert(&aqt->q, "\n", 1, 1);
83                if (!sub)
84                    return AVERROR(ENOMEM);
85            }
86            sub = ff_subtitles_queue_insert(&aqt->q, line, strlen(line), !new_event);
87            if (!sub)
88                return AVERROR(ENOMEM);
89            if (new_event) {
90                sub->pts = frame;
91                sub->duration = -1;
92                sub->pos = pos;
93            }
94            new_event = 0;
95        }
96    }
97
98    ff_subtitles_queue_finalize(&aqt->q);
99    return 0;
100}
101
102static int aqt_read_packet(AVFormatContext *s, AVPacket *pkt)
103{
104    AQTitleContext *aqt = s->priv_data;
105    return ff_subtitles_queue_read_packet(&aqt->q, pkt);
106}
107
108static int aqt_read_seek(AVFormatContext *s, int stream_index,
109                         int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
110{
111    AQTitleContext *aqt = s->priv_data;
112    return ff_subtitles_queue_seek(&aqt->q, s, stream_index,
113                                   min_ts, ts, max_ts, flags);
114}
115
116static int aqt_read_close(AVFormatContext *s)
117{
118    AQTitleContext *aqt = s->priv_data;
119    ff_subtitles_queue_clean(&aqt->q);
120    return 0;
121}
122
123#define OFFSET(x) offsetof(AQTitleContext, x)
124#define SD AV_OPT_FLAG_SUBTITLE_PARAM|AV_OPT_FLAG_DECODING_PARAM
125static const AVOption aqt_options[] = {
126    { "subfps", "set the movie frame rate", OFFSET(frame_rate), AV_OPT_TYPE_RATIONAL, {.dbl=25}, 0, INT_MAX, SD },
127    { NULL }
128};
129
130static const AVClass aqt_class = {
131    .class_name = "aqtdec",
132    .item_name  = av_default_item_name,
133    .option     = aqt_options,
134    .version    = LIBAVUTIL_VERSION_INT,
135};
136
137AVInputFormat ff_aqtitle_demuxer = {
138    .name           = "aqtitle",
139    .long_name      = NULL_IF_CONFIG_SMALL("AQTitle subtitles"),
140    .priv_data_size = sizeof(AQTitleContext),
141    .read_probe     = aqt_probe,
142    .read_header    = aqt_read_header,
143    .read_packet    = aqt_read_packet,
144    .read_seek2     = aqt_read_seek,
145    .read_close     = aqt_read_close,
146    .extensions     = "aqt",
147    .priv_class     = &aqt_class,
148};
149