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