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 "avformat.h" 24#include "id3v2.h" 25#include "id3v1.h" 26 27typedef struct { 28 int totalframes, currentframe; 29} TTAContext; 30 31static int tta_probe(AVProbeData *p) 32{ 33 const uint8_t *d = p->buf; 34 35 if (ff_id3v2_match(d)) 36 d += ff_id3v2_tag_len(d); 37 38 if (d - p->buf >= p->buf_size) 39 return 0; 40 41 if (d[0] == 'T' && d[1] == 'T' && d[2] == 'A' && d[3] == '1') 42 return 80; 43 return 0; 44} 45 46static int tta_read_header(AVFormatContext *s, AVFormatParameters *ap) 47{ 48 TTAContext *c = s->priv_data; 49 AVStream *st; 50 int i, channels, bps, samplerate, datalen, framelen; 51 uint64_t framepos, start_offset; 52 53 ff_id3v2_read(s); 54 if (!av_metadata_get(s->metadata, "", NULL, AV_METADATA_IGNORE_SUFFIX)) 55 ff_id3v1_read(s); 56 57 start_offset = url_ftell(s->pb); 58 if (get_le32(s->pb) != AV_RL32("TTA1")) 59 return -1; // not tta file 60 61 url_fskip(s->pb, 2); // FIXME: flags 62 channels = get_le16(s->pb); 63 bps = get_le16(s->pb); 64 samplerate = get_le32(s->pb); 65 if(samplerate <= 0 || samplerate > 1000000){ 66 av_log(s, AV_LOG_ERROR, "nonsense samplerate\n"); 67 return -1; 68 } 69 70 datalen = get_le32(s->pb); 71 if(datalen < 0){ 72 av_log(s, AV_LOG_ERROR, "nonsense datalen\n"); 73 return -1; 74 } 75 76 url_fskip(s->pb, 4); // header crc 77 78 framelen = samplerate*256/245; 79 c->totalframes = datalen / framelen + ((datalen % framelen) ? 1 : 0); 80 c->currentframe = 0; 81 82 if(c->totalframes >= UINT_MAX/sizeof(uint32_t)){ 83 av_log(s, AV_LOG_ERROR, "totalframes too large\n"); 84 return -1; 85 } 86 87 st = av_new_stream(s, 0); 88 if (!st) 89 return AVERROR(ENOMEM); 90 91 av_set_pts_info(st, 64, 1, samplerate); 92 st->start_time = 0; 93 st->duration = datalen; 94 95 framepos = url_ftell(s->pb) + 4*c->totalframes + 4; 96 97 for (i = 0; i < c->totalframes; i++) { 98 uint32_t size = get_le32(s->pb); 99 av_add_index_entry(st, framepos, i*framelen, size, 0, AVINDEX_KEYFRAME); 100 framepos += size; 101 } 102 url_fskip(s->pb, 4); // seektable crc 103 104 st->codec->codec_type = AVMEDIA_TYPE_AUDIO; 105 st->codec->codec_id = CODEC_ID_TTA; 106 st->codec->channels = channels; 107 st->codec->sample_rate = samplerate; 108 st->codec->bits_per_coded_sample = bps; 109 110 st->codec->extradata_size = url_ftell(s->pb) - start_offset; 111 if(st->codec->extradata_size+FF_INPUT_BUFFER_PADDING_SIZE <= (unsigned)st->codec->extradata_size){ 112 //this check is redundant as get_buffer should fail 113 av_log(s, AV_LOG_ERROR, "extradata_size too large\n"); 114 return -1; 115 } 116 st->codec->extradata = av_mallocz(st->codec->extradata_size+FF_INPUT_BUFFER_PADDING_SIZE); 117 url_fseek(s->pb, start_offset, SEEK_SET); 118 get_buffer(s->pb, st->codec->extradata, st->codec->extradata_size); 119 120 return 0; 121} 122 123static int tta_read_packet(AVFormatContext *s, AVPacket *pkt) 124{ 125 TTAContext *c = s->priv_data; 126 AVStream *st = s->streams[0]; 127 int size, ret; 128 129 // FIXME! 130 if (c->currentframe > c->totalframes) 131 return -1; 132 133 size = st->index_entries[c->currentframe].size; 134 135 ret = av_get_packet(s->pb, pkt, size); 136 pkt->dts = st->index_entries[c->currentframe++].timestamp; 137 return ret; 138} 139 140static int tta_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) 141{ 142 TTAContext *c = s->priv_data; 143 AVStream *st = s->streams[stream_index]; 144 int index = av_index_search_timestamp(st, timestamp, flags); 145 if (index < 0) 146 return -1; 147 148 c->currentframe = index; 149 url_fseek(s->pb, st->index_entries[index].pos, SEEK_SET); 150 151 return 0; 152} 153 154AVInputFormat tta_demuxer = { 155 "tta", 156 NULL_IF_CONFIG_SMALL("True Audio"), 157 sizeof(TTAContext), 158 tta_probe, 159 tta_read_header, 160 tta_read_packet, 161 NULL, 162 tta_read_seek, 163 .extensions = "tta", 164}; 165