1/* 2 * Copyright (c) 2014 Eejya Singh 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 * STL subtitles format demuxer 24 * @see https://documentation.apple.com/en/dvdstudiopro/usermanual/index.html#chapter=19%26section=13%26tasks=true 25 */ 26 27#include "avformat.h" 28#include "internal.h" 29#include "subtitles.h" 30#include "libavutil/intreadwrite.h" 31#include "libavutil/avstring.h" 32 33typedef struct { 34 FFDemuxSubtitlesQueue q; 35} STLContext; 36 37static int stl_probe(const AVProbeData *p) 38{ 39 char c; 40 const unsigned char *ptr = p->buf; 41 42 if (AV_RB24(ptr) == 0xEFBBBF) 43 ptr += 3; /* skip UTF-8 BOM */ 44 45 while (*ptr == '\r' || *ptr == '\n' || *ptr == '$' || !strncmp(ptr, "//" , 2)) 46 ptr += ff_subtitles_next_line(ptr); 47 48 if (sscanf(ptr, "%*d:%*d:%*d:%*d , %*d:%*d:%*d:%*d , %c", &c) == 1) 49 return AVPROBE_SCORE_MAX; 50 51 return 0; 52} 53 54static int64_t get_pts(char **buf, int *duration) 55{ 56 int hh1, mm1, ss1, ms1; 57 int hh2, mm2, ss2, ms2; 58 int len = 0; 59 60 if (sscanf(*buf, "%2d:%2d:%2d:%2d , %2d:%2d:%2d:%2d , %n", 61 &hh1, &mm1, &ss1, &ms1, 62 &hh2, &mm2, &ss2, &ms2, &len) >= 8 && len > 0) { 63 int64_t start = (hh1*3600LL + mm1*60LL + ss1) * 100LL + ms1; 64 int64_t end = (hh2*3600LL + mm2*60LL + ss2) * 100LL + ms2; 65 *duration = end - start; 66 *buf += len; 67 return start; 68 } 69 return AV_NOPTS_VALUE; 70} 71 72static int stl_read_header(AVFormatContext *s) 73{ 74 STLContext *stl = s->priv_data; 75 AVStream *st = avformat_new_stream(s, NULL); 76 77 if (!st) 78 return AVERROR(ENOMEM); 79 avpriv_set_pts_info(st, 64, 1, 100); 80 st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE; 81 st->codecpar->codec_id = AV_CODEC_ID_STL; 82 83 while (!avio_feof(s->pb)) { 84 char line[4096]; 85 char *p = line; 86 const int64_t pos = avio_tell(s->pb); 87 int len = ff_get_line(s->pb, line, sizeof(line)); 88 int64_t pts_start; 89 int duration; 90 91 if (!len) 92 break; 93 94 line[strcspn(line, "\r\n")] = 0; 95 pts_start = get_pts(&p , &duration); 96 97 if (pts_start != AV_NOPTS_VALUE) { 98 AVPacket *sub; 99 sub = ff_subtitles_queue_insert(&stl->q, p, strlen(p), 0); 100 if (!sub) 101 return AVERROR(ENOMEM); 102 sub->pos = pos; 103 sub->pts = pts_start; 104 sub->duration = duration; 105 } 106 } 107 ff_subtitles_queue_finalize(s, &stl->q); 108 return 0; 109} 110 111const AVInputFormat ff_stl_demuxer = { 112 .name = "stl", 113 .long_name = NULL_IF_CONFIG_SMALL("Spruce subtitle format"), 114 .priv_data_size = sizeof(STLContext), 115 .flags_internal = FF_FMT_INIT_CLEANUP, 116 .read_probe = stl_probe, 117 .read_header = stl_read_header, 118 .extensions = "stl", 119 .read_packet = ff_subtitles_read_packet, 120 .read_seek2 = ff_subtitles_read_seek, 121 .read_close = ff_subtitles_read_close, 122}; 123