3 * Copyright (c) 2008 Michael Niedermayer
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 typedef struct ASSContext{
25 unsigned int extra_index;
28 static int write_header(AVFormatContext *s)
30 ASSContext *ass = s->priv_data;
31 AVCodecContext *avctx= s->streams[0]->codec;
34 if(s->nb_streams != 1 || avctx->codec_id != CODEC_ID_SSA){
35 av_log(s, AV_LOG_ERROR, "Exactly one ASS/SSA stream is needed.\n");
39 while(ass->extra_index < avctx->extradata_size){
40 uint8_t *p = avctx->extradata + ass->extra_index;
41 uint8_t *end= strchr(p, '\n');
42 if(!end) end= avctx->extradata + avctx->extradata_size;
45 avio_write(s->pb, p, end-p);
46 ass->extra_index += end-p;
48 if(last && !memcmp(last, "[Events]", 8))
53 put_flush_packet(s->pb);
58 static int write_packet(AVFormatContext *s, AVPacket *pkt)
60 avio_write(s->pb, pkt->data, pkt->size);
62 put_flush_packet(s->pb);
67 static int write_trailer(AVFormatContext *s)
69 ASSContext *ass = s->priv_data;
70 AVCodecContext *avctx= s->streams[0]->codec;
72 avio_write(s->pb, avctx->extradata + ass->extra_index,
73 avctx->extradata_size - ass->extra_index);
75 put_flush_packet(s->pb);
80 AVOutputFormat ff_ass_muxer = {
82 .long_name = NULL_IF_CONFIG_SMALL("Advanced SubStation Alpha subtitle format"),
83 .mime_type = "text/x-ssa",
84 .extensions = "ass,ssa",
85 .priv_data_size = sizeof(ASSContext),
86 .subtitle_codec = CODEC_ID_SSA,
87 .write_header = write_header,
88 .write_packet = write_packet,
89 .write_trailer = write_trailer,
90 .flags = AVFMT_GLOBALHEADER | AVFMT_NOTIMESTAMPS,