1/* 2 * TTA demuxer 3 * Copyright (c) 2006 Alex Beregszaszi 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 "libavcodec/get_bits.h" 23#include "apetag.h" 24#include "avformat.h" 25#include "avio_internal.h" 26#include "internal.h" 27#include "id3v1.h" 28#include "libavutil/crc.h" 29#include "libavutil/dict.h" 30 31typedef struct { 32 int totalframes, currentframe; 33 int frame_size; 34 int last_frame_size; 35} TTAContext; 36 37static unsigned long tta_check_crc(unsigned long checksum, const uint8_t *buf, 38 unsigned int len) 39{ 40 return av_crc(av_crc_get_table(AV_CRC_32_IEEE_LE), checksum, buf, len); 41} 42 43static int tta_probe(AVProbeData *p) 44{ 45 if (AV_RL32(&p->buf[0]) == MKTAG('T', 'T', 'A', '1') && 46 (AV_RL16(&p->buf[4]) == 1 || AV_RL16(&p->buf[4]) == 2) && 47 AV_RL16(&p->buf[6]) > 0 && 48 AV_RL16(&p->buf[8]) > 0 && 49 AV_RL32(&p->buf[10]) > 0) 50 return AVPROBE_SCORE_EXTENSION + 30; 51 return 0; 52} 53 54static int tta_read_header(AVFormatContext *s) 55{ 56 TTAContext *c = s->priv_data; 57 AVStream *st; 58 int i, channels, bps, samplerate; 59 uint64_t framepos, start_offset; 60 uint32_t nb_samples, crc; 61 62 ff_id3v1_read(s); 63 64 start_offset = avio_tell(s->pb); 65 ffio_init_checksum(s->pb, tta_check_crc, UINT32_MAX); 66 if (avio_rl32(s->pb) != AV_RL32("TTA1")) 67 return AVERROR_INVALIDDATA; 68 69 avio_skip(s->pb, 2); // FIXME: flags 70 channels = avio_rl16(s->pb); 71 bps = avio_rl16(s->pb); 72 samplerate = avio_rl32(s->pb); 73 if(samplerate <= 0 || samplerate > 1000000){ 74 av_log(s, AV_LOG_ERROR, "nonsense samplerate\n"); 75 return AVERROR_INVALIDDATA; 76 } 77 78 nb_samples = avio_rl32(s->pb); 79 if (!nb_samples) { 80 av_log(s, AV_LOG_ERROR, "invalid number of samples\n"); 81 return AVERROR_INVALIDDATA; 82 } 83 84 crc = ffio_get_checksum(s->pb) ^ UINT32_MAX; 85 if (crc != avio_rl32(s->pb)) { 86 av_log(s, AV_LOG_ERROR, "Header CRC error\n"); 87 return AVERROR_INVALIDDATA; 88 } 89 90 c->frame_size = samplerate * 256 / 245; 91 c->last_frame_size = nb_samples % c->frame_size; 92 if (!c->last_frame_size) 93 c->last_frame_size = c->frame_size; 94 c->totalframes = nb_samples / c->frame_size + (c->last_frame_size < c->frame_size); 95 c->currentframe = 0; 96 97 if(c->totalframes >= UINT_MAX/sizeof(uint32_t) || c->totalframes <= 0){ 98 av_log(s, AV_LOG_ERROR, "totalframes %d invalid\n", c->totalframes); 99 return AVERROR_INVALIDDATA; 100 } 101 102 st = avformat_new_stream(s, NULL); 103 if (!st) 104 return AVERROR(ENOMEM); 105 106 avpriv_set_pts_info(st, 64, 1, samplerate); 107 st->start_time = 0; 108 st->duration = nb_samples; 109 110 framepos = avio_tell(s->pb) + 4*c->totalframes + 4; 111 112 if (ff_alloc_extradata(st->codec, avio_tell(s->pb) - start_offset)) 113 return AVERROR(ENOMEM); 114 115 avio_seek(s->pb, start_offset, SEEK_SET); 116 avio_read(s->pb, st->codec->extradata, st->codec->extradata_size); 117 118 ffio_init_checksum(s->pb, tta_check_crc, UINT32_MAX); 119 for (i = 0; i < c->totalframes; i++) { 120 uint32_t size = avio_rl32(s->pb); 121 av_add_index_entry(st, framepos, i * c->frame_size, size, 0, 122 AVINDEX_KEYFRAME); 123 framepos += size; 124 } 125 crc = ffio_get_checksum(s->pb) ^ UINT32_MAX; 126 if (crc != avio_rl32(s->pb)) { 127 av_log(s, AV_LOG_ERROR, "Seek table CRC error\n"); 128 return AVERROR_INVALIDDATA; 129 } 130 131 st->codec->codec_type = AVMEDIA_TYPE_AUDIO; 132 st->codec->codec_id = AV_CODEC_ID_TTA; 133 st->codec->channels = channels; 134 st->codec->sample_rate = samplerate; 135 st->codec->bits_per_coded_sample = bps; 136 137 if (s->pb->seekable) { 138 int64_t pos = avio_tell(s->pb); 139 ff_ape_parse_tag(s); 140 avio_seek(s->pb, pos, SEEK_SET); 141 } 142 143 return 0; 144} 145 146static int tta_read_packet(AVFormatContext *s, AVPacket *pkt) 147{ 148 TTAContext *c = s->priv_data; 149 AVStream *st = s->streams[0]; 150 int size, ret; 151 152 // FIXME! 153 if (c->currentframe >= c->totalframes) 154 return AVERROR_EOF; 155 156 size = st->index_entries[c->currentframe].size; 157 158 ret = av_get_packet(s->pb, pkt, size); 159 pkt->dts = st->index_entries[c->currentframe++].timestamp; 160 pkt->duration = c->currentframe == c->totalframes ? c->last_frame_size : 161 c->frame_size; 162 return ret; 163} 164 165static int tta_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) 166{ 167 TTAContext *c = s->priv_data; 168 AVStream *st = s->streams[stream_index]; 169 int index = av_index_search_timestamp(st, timestamp, flags); 170 if (index < 0) 171 return -1; 172 if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0) 173 return -1; 174 175 c->currentframe = index; 176 177 return 0; 178} 179 180AVInputFormat ff_tta_demuxer = { 181 .name = "tta", 182 .long_name = NULL_IF_CONFIG_SMALL("TTA (True Audio)"), 183 .priv_data_size = sizeof(TTAContext), 184 .read_probe = tta_probe, 185 .read_header = tta_read_header, 186 .read_packet = tta_read_packet, 187 .read_seek = tta_read_seek, 188 .extensions = "tta", 189}; 190