1/* 2 * Copyright (C) 2010 David Conrad 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#include "libavcodec/bytestream.h" 22#include "avformat.h" 23#include "internal.h" 24#include "oggdec.h" 25 26static int skeleton_header(AVFormatContext *s, int idx) 27{ 28 struct ogg *ogg = s->priv_data; 29 struct ogg_stream *os = ogg->streams + idx; 30 AVStream *st = s->streams[idx]; 31 uint8_t *buf = os->buf + os->pstart; 32 int version_major, version_minor; 33 int64_t start_num, start_den; 34 uint64_t start_granule; 35 int target_idx, start_time; 36 37 st->codec->codec_type = AVMEDIA_TYPE_DATA; 38 39 if ((os->flags & OGG_FLAG_EOS) && os->psize == 0) 40 return 1; 41 42 if (os->psize < 8) 43 return -1; 44 45 if (!strncmp(buf, "fishead", 8)) { 46 if (os->psize < 64) 47 return -1; 48 49 version_major = AV_RL16(buf+8); 50 version_minor = AV_RL16(buf+10); 51 52 if (version_major != 3 && version_major != 4) { 53 av_log(s, AV_LOG_WARNING, "Unknown skeleton version %d.%d\n", 54 version_major, version_minor); 55 return -1; 56 } 57 58 // This is the overall start time. We use it for the start time of 59 // of the skeleton stream since if left unset lavf assumes 0, 60 // which we don't want since skeleton is timeless 61 // FIXME: the real meaning of this field is "start playback at 62 // this time which can be in the middle of a packet 63 start_num = AV_RL64(buf+12); 64 start_den = AV_RL64(buf+20); 65 66 if (start_den > 0 && start_num > 0) { 67 int base_den; 68 av_reduce(&start_time, &base_den, start_num, start_den, INT_MAX); 69 avpriv_set_pts_info(st, 64, 1, base_den); 70 os->lastpts = 71 st->start_time = start_time; 72 } 73 } else if (!strncmp(buf, "fisbone", 8)) { 74 if (os->psize < 52) 75 return -1; 76 77 target_idx = ogg_find_stream(ogg, AV_RL32(buf+12)); 78 start_granule = AV_RL64(buf+36); 79 if (target_idx < 0) { 80 av_log(s, AV_LOG_WARNING, "Serial number in fisbone doesn't match any stream\n"); 81 return 1; 82 } 83 os = ogg->streams + target_idx; 84 if (os->start_granule != OGG_NOGRANULE_VALUE) { 85 av_log(s, AV_LOG_WARNING, "Multiple fisbone for the same stream\n"); 86 return 1; 87 } 88 if (start_granule != OGG_NOGRANULE_VALUE) { 89 os->start_granule = start_granule; 90 } 91 } 92 93 return 1; 94} 95 96const struct ogg_codec ff_skeleton_codec = { 97 .magic = "fishead", 98 .magicsize = 8, 99 .header = skeleton_header, 100 .nb_header = 0, 101}; 102