mirror of https://github.com/FFmpeg/FFmpeg.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
101 lines
3.1 KiB
101 lines
3.1 KiB
12 years ago
|
/*
|
||
|
|
* 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
|
||
|
|
* WebVTT subtitle decoder
|
||
|
|
* @see http://dev.w3.org/html5/webvtt/
|
||
|
|
* @todo need to support extended markups and cue settings
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "avcodec.h"
|
||
|
|
#include "ass.h"
|
||
|
|
#include "libavutil/bprint.h"
|
||
|
|
|
||
|
|
static const struct {
|
||
|
|
const char *from;
|
||
|
|
const char *to;
|
||
|
|
} webvtt_tag_replace[] = {
|
||
|
|
{"<i>", "{\\i1}"}, {"</i>", "{\\i0}"},
|
||
|
|
{"<b>", "{\\b1}"}, {"</b>", "{\\b0}"},
|
||
|
|
{"<u>", "{\\u1}"}, {"</u>", "{\\u0}"},
|
||
|
|
{"{", "\\{"}, {"}", "\\}"}, // escape to avoid ASS markup conflicts
|
||
|
|
};
|
||
|
|
|
||
|
|
static int webvtt_event_to_ass(AVBPrint *buf, const char *p)
|
||
|
|
{
|
||
|
|
int i, skip = 0;
|
||
|
|
|
||
|
|
while (*p) {
|
||
|
|
|
||
|
|
for (i = 0; i < FF_ARRAY_ELEMS(webvtt_tag_replace); i++) {
|
||
|
|
const char *from = webvtt_tag_replace[i].from;
|
||
|
|
const size_t len = strlen(from);
|
||
|
|
if (!strncmp(p, from, len)) {
|
||
|
|
av_bprintf(buf, "%s", webvtt_tag_replace[i].to);
|
||
|
|
p += len;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if (!*p)
|
||
|
|
break;
|
||
|
|
|
||
|
|
if (*p == '<')
|
||
|
|
skip = 1;
|
||
|
|
else if (*p == '>')
|
||
|
|
skip = 0;
|
||
|
|
else if (p[0] == '\n' && p[1])
|
||
|
|
av_bprintf(buf, "\\N");
|
||
|
|
else if (!skip && *p != '\r')
|
||
|
|
av_bprint_chars(buf, *p, 1);
|
||
|
|
p++;
|
||
|
|
}
|
||
|
|
av_bprintf(buf, "\r\n");
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int webvtt_decode_frame(AVCodecContext *avctx,
|
||
|
|
void *data, int *got_sub_ptr, AVPacket *avpkt)
|
||
|
|
{
|
||
|
|
AVSubtitle *sub = data;
|
||
|
|
const char *ptr = avpkt->data;
|
||
|
|
AVBPrint buf;
|
||
|
|
|
||
|
|
av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED);
|
||
|
|
if (ptr && avpkt->size > 0 && !webvtt_event_to_ass(&buf, ptr)) {
|
||
|
|
int ts_start = av_rescale_q(avpkt->pts, avctx->time_base, (AVRational){1,100});
|
||
|
|
int ts_duration = avpkt->duration != -1 ?
|
||
|
|
av_rescale_q(avpkt->duration, avctx->time_base, (AVRational){1,100}) : -1;
|
||
|
|
ff_ass_add_rect(sub, buf.str, ts_start, ts_duration, 0);
|
||
|
|
}
|
||
|
|
*got_sub_ptr = sub->num_rects > 0;
|
||
|
|
av_bprint_finalize(&buf, NULL);
|
||
|
|
return avpkt->size;
|
||
|
|
}
|
||
|
|
|
||
|
|
AVCodec ff_webvtt_decoder = {
|
||
|
|
.name = "webvtt",
|
||
|
|
.long_name = NULL_IF_CONFIG_SMALL("WebVTT subtitle"),
|
||
|
|
.type = AVMEDIA_TYPE_SUBTITLE,
|
||
|
|
.id = AV_CODEC_ID_WEBVTT,
|
||
|
|
.decode = webvtt_decode_frame,
|
||
|
|
.init = ff_ass_subtitle_header_default,
|
||
|
|
};
|