mirror of
https://git.ffmpeg.org/ffmpeg.git
synced 2024-12-29 19:02:21 +00:00
130 lines
3.9 KiB
C
130 lines
3.9 KiB
C
/*
|
|
* MicroDVD subtitle demuxer
|
|
* Copyright (c) 2010 Aurelien Jacobs <aurel@gnuage.org>
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
#include "avformat.h"
|
|
#include "internal.h"
|
|
#include "libavutil/intreadwrite.h"
|
|
|
|
#define MAX_LINESIZE 2048
|
|
|
|
|
|
typedef struct {
|
|
uint8_t lines[3][MAX_LINESIZE];
|
|
int64_t pos[3];
|
|
} MicroDVDContext;
|
|
|
|
|
|
static int microdvd_probe(AVProbeData *p)
|
|
{
|
|
unsigned char c, *ptr = p->buf;
|
|
int i;
|
|
|
|
if (AV_RB24(ptr) == 0xEFBBBF)
|
|
ptr += 3; /* skip UTF-8 BOM */
|
|
|
|
for (i=0; i<3; i++) {
|
|
if (sscanf(ptr, "{%*d}{}%c", &c) != 1 &&
|
|
sscanf(ptr, "{%*d}{%*d}%c", &c) != 1 &&
|
|
sscanf(ptr, "{DEFAULT}{}%c", &c) != 1)
|
|
return 0;
|
|
ptr += strcspn(ptr, "\n") + 1;
|
|
}
|
|
return AVPROBE_SCORE_MAX;
|
|
}
|
|
|
|
static int microdvd_read_header(AVFormatContext *s, AVFormatParameters *ap)
|
|
{
|
|
AVRational pts_info = (AVRational){ 2997, 125 }; /* default: 23.976 fps */
|
|
MicroDVDContext *microdvd = s->priv_data;
|
|
AVStream *st = avformat_new_stream(s, NULL);
|
|
int i, frame;
|
|
double fps;
|
|
char c;
|
|
|
|
if (!st)
|
|
return -1;
|
|
for (i=0; i<FF_ARRAY_ELEMS(microdvd->lines); i++) {
|
|
microdvd->pos[i] = avio_tell(s->pb);
|
|
ff_get_line(s->pb, microdvd->lines[i], sizeof(microdvd->lines[i]));
|
|
if ((sscanf(microdvd->lines[i], "{%d}{}%6lf", &frame, &fps) == 2 ||
|
|
sscanf(microdvd->lines[i], "{%d}{%*d}%6lf", &frame, &fps) == 2)
|
|
&& frame <= 1 && fps > 3 && fps < 100)
|
|
pts_info = av_d2q(fps, 100000);
|
|
if (sscanf(microdvd->lines[i], "{DEFAULT}{}%c", &c) == 1) {
|
|
st->codec->extradata = av_strdup(microdvd->lines[i] + 11);
|
|
st->codec->extradata_size = strlen(st->codec->extradata);
|
|
i--;
|
|
}
|
|
}
|
|
av_set_pts_info(st, 64, pts_info.den, pts_info.num);
|
|
st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
|
|
st->codec->codec_id = CODEC_ID_MICRODVD;
|
|
return 0;
|
|
}
|
|
|
|
static int64_t get_pts(const char *buf)
|
|
{
|
|
int frame;
|
|
char c;
|
|
|
|
if (sscanf(buf, "{%d}{%c", &frame, &c) == 2)
|
|
return frame;
|
|
return AV_NOPTS_VALUE;
|
|
}
|
|
|
|
static int microdvd_read_packet(AVFormatContext *s, AVPacket *pkt)
|
|
{
|
|
MicroDVDContext *microdvd = s->priv_data;
|
|
char buffer[MAX_LINESIZE];
|
|
int64_t pos = avio_tell(s->pb);
|
|
int i, len = 0, res = AVERROR_EOF;
|
|
|
|
for (i=0; i<FF_ARRAY_ELEMS(microdvd->lines); i++) {
|
|
if (microdvd->lines[i][0]) {
|
|
strcpy(buffer, microdvd->lines[i]);
|
|
pos = microdvd->pos[i];
|
|
len = strlen(buffer);
|
|
microdvd->lines[i][0] = 0;
|
|
break;
|
|
}
|
|
}
|
|
if (!len)
|
|
len = ff_get_line(s->pb, buffer, sizeof(buffer));
|
|
|
|
if (buffer[0] && !(res = av_new_packet(pkt, len))) {
|
|
memcpy(pkt->data, buffer, len);
|
|
pkt->flags |= AV_PKT_FLAG_KEY;
|
|
pkt->pos = pos;
|
|
pkt->pts = pkt->dts = get_pts(buffer);
|
|
}
|
|
return res;
|
|
}
|
|
|
|
AVInputFormat ff_microdvd_demuxer = {
|
|
.name = "microdvd",
|
|
.long_name = NULL_IF_CONFIG_SMALL("MicroDVD subtitle format"),
|
|
.priv_data_size = sizeof(MicroDVDContext),
|
|
.read_probe = microdvd_probe,
|
|
.read_header = microdvd_read_header,
|
|
.read_packet = microdvd_read_packet,
|
|
.flags = AVFMT_GENERIC_INDEX,
|
|
};
|