1/* 2 * SSA/ASS muxer 3 * Copyright (c) 2008 Michael Niedermayer 4 * 5 * This file is part of FFmpeg. 6 * 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. 11 * 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. 16 * 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 20 */ 21 22#include "avformat.h" 23#include "internal.h" 24 25typedef struct ASSContext{ 26 unsigned int extra_index; 27 int write_ts; // 0: ssa (timing in payload), 1: ass (matroska like) 28}ASSContext; 29 30static int write_header(AVFormatContext *s) 31{ 32 ASSContext *ass = s->priv_data; 33 AVCodecContext *avctx= s->streams[0]->codec; 34 uint8_t *last= NULL; 35 36 if (s->nb_streams != 1 || (avctx->codec_id != AV_CODEC_ID_SSA && 37 avctx->codec_id != AV_CODEC_ID_ASS)) { 38 av_log(s, AV_LOG_ERROR, "Exactly one ASS/SSA stream is needed.\n"); 39 return -1; 40 } 41 ass->write_ts = avctx->codec_id == AV_CODEC_ID_ASS; 42 avpriv_set_pts_info(s->streams[0], 64, 1, 100); 43 44 while(ass->extra_index < avctx->extradata_size){ 45 uint8_t *p = avctx->extradata + ass->extra_index; 46 uint8_t *end= strchr(p, '\n'); 47 if(!end) end= avctx->extradata + avctx->extradata_size; 48 else end++; 49 50 avio_write(s->pb, p, end-p); 51 ass->extra_index += end-p; 52 53 if(last && !memcmp(last, "[Events]", 8)) 54 break; 55 last=p; 56 } 57 58 avio_flush(s->pb); 59 60 return 0; 61} 62 63static int write_packet(AVFormatContext *s, AVPacket *pkt) 64{ 65 ASSContext *ass = s->priv_data; 66 67 if (ass->write_ts) { 68 long int layer; 69 char *p; 70 int64_t start = pkt->pts; 71 int64_t end = start + pkt->duration; 72 int hh1, mm1, ss1, ms1; 73 int hh2, mm2, ss2, ms2; 74 75 p = pkt->data + strcspn(pkt->data, ",") + 1; // skip ReadOrder 76 layer = strtol(p, &p, 10); 77 if (*p == ',') 78 p++; 79 hh1 = (int)(start / 360000); mm1 = (int)(start / 6000) % 60; 80 hh2 = (int)(end / 360000); mm2 = (int)(end / 6000) % 60; 81 ss1 = (int)(start / 100) % 60; ms1 = (int)(start % 100); 82 ss2 = (int)(end / 100) % 60; ms2 = (int)(end % 100); 83 if (hh1 > 9) hh1 = 9, mm1 = 59, ss1 = 59, ms1 = 99; 84 if (hh2 > 9) hh2 = 9, mm2 = 59, ss2 = 59, ms2 = 99; 85 avio_printf(s->pb, "Dialogue: %ld,%d:%02d:%02d.%02d,%d:%02d:%02d.%02d,%s\r\n", 86 layer, hh1, mm1, ss1, ms1, hh2, mm2, ss2, ms2, p); 87 } else { 88 avio_write(s->pb, pkt->data, pkt->size); 89 } 90 91 return 0; 92} 93 94static int write_trailer(AVFormatContext *s) 95{ 96 ASSContext *ass = s->priv_data; 97 AVCodecContext *avctx= s->streams[0]->codec; 98 99 avio_write(s->pb, avctx->extradata + ass->extra_index, 100 avctx->extradata_size - ass->extra_index); 101 102 return 0; 103} 104 105AVOutputFormat ff_ass_muxer = { 106 .name = "ass", 107 .long_name = NULL_IF_CONFIG_SMALL("SSA (SubStation Alpha) subtitle"), 108 .mime_type = "text/x-ssa", 109 .extensions = "ass,ssa", 110 .priv_data_size = sizeof(ASSContext), 111 .subtitle_codec = AV_CODEC_ID_SSA, 112 .write_header = write_header, 113 .write_packet = write_packet, 114 .write_trailer = write_trailer, 115 .flags = AVFMT_GLOBALHEADER | AVFMT_NOTIMESTAMPS | AVFMT_TS_NONSTRICT, 116}; 117