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