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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 "libavutil/crc.h"
23 #include "libavutil/dict.h"
24 #include "libavutil/intreadwrite.h"
25 
26 #include "apetag.h"
27 #include "avformat.h"
28 #include "avio_internal.h"
29 #include "internal.h"
30 #include "id3v1.h"
31 
32 typedef struct TTAContext {
33     int totalframes, currentframe;
34     int frame_size;
35     int last_frame_size;
36 } TTAContext;
37 
tta_probe(const AVProbeData * p)38 static int tta_probe(const AVProbeData *p)
39 {
40     if (AV_RL32(&p->buf[0]) == MKTAG('T', 'T', 'A', '1') &&
41         (AV_RL16(&p->buf[4]) == 1 || AV_RL16(&p->buf[4]) == 2) &&
42         AV_RL16(&p->buf[6]) > 0 &&
43         AV_RL16(&p->buf[8]) > 0 &&
44         AV_RL32(&p->buf[10]) > 0)
45         return AVPROBE_SCORE_EXTENSION + 30;
46     return 0;
47 }
48 
tta_read_header(AVFormatContext * s)49 static int tta_read_header(AVFormatContext *s)
50 {
51     TTAContext *c = s->priv_data;
52     AVStream *st;
53     int i, channels, bps, samplerate;
54     int64_t framepos, start_offset;
55     uint32_t nb_samples, crc;
56 
57     ff_id3v1_read(s);
58 
59     start_offset = avio_tell(s->pb);
60     if (start_offset < 0)
61         return start_offset;
62     ffio_init_checksum(s->pb, ff_crcEDB88320_update, UINT32_MAX);
63     if (avio_rl32(s->pb) != AV_RL32("TTA1"))
64         return AVERROR_INVALIDDATA;
65 
66     avio_skip(s->pb, 2); // FIXME: flags
67     channels = avio_rl16(s->pb);
68     bps = avio_rl16(s->pb);
69     samplerate = avio_rl32(s->pb);
70     if(samplerate <= 0 || samplerate > 1000000){
71         av_log(s, AV_LOG_ERROR, "nonsense samplerate\n");
72         return AVERROR_INVALIDDATA;
73     }
74 
75     nb_samples = avio_rl32(s->pb);
76     if (!nb_samples) {
77         av_log(s, AV_LOG_ERROR, "invalid number of samples\n");
78         return AVERROR_INVALIDDATA;
79     }
80 
81     crc = ffio_get_checksum(s->pb) ^ UINT32_MAX;
82     if (crc != avio_rl32(s->pb) && s->error_recognition & AV_EF_CRCCHECK) {
83         av_log(s, AV_LOG_ERROR, "Header CRC error\n");
84         return AVERROR_INVALIDDATA;
85     }
86 
87     c->frame_size      = samplerate * 256 / 245;
88     c->last_frame_size = nb_samples % c->frame_size;
89     if (!c->last_frame_size)
90         c->last_frame_size = c->frame_size;
91     c->totalframes = nb_samples / c->frame_size + (c->last_frame_size < c->frame_size);
92     c->currentframe = 0;
93 
94     if(c->totalframes >= UINT_MAX/sizeof(uint32_t) || c->totalframes <= 0){
95         av_log(s, AV_LOG_ERROR, "totalframes %d invalid\n", c->totalframes);
96         return AVERROR_INVALIDDATA;
97     }
98 
99     st = avformat_new_stream(s, NULL);
100     if (!st)
101         return AVERROR(ENOMEM);
102 
103     avpriv_set_pts_info(st, 64, 1, samplerate);
104     st->start_time = 0;
105     st->duration = nb_samples;
106 
107     framepos = avio_tell(s->pb);
108     if (framepos < 0)
109         return framepos;
110     framepos += 4 * c->totalframes + 4;
111 
112     if (ff_alloc_extradata(st->codecpar, 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->codecpar->extradata, st->codecpar->extradata_size);
117 
118     ffio_init_checksum(s->pb, ff_crcEDB88320_update, UINT32_MAX);
119     for (i = 0; i < c->totalframes; i++) {
120         uint32_t size = avio_rl32(s->pb);
121         int r;
122         if (avio_feof(s->pb))
123             return AVERROR_INVALIDDATA;
124         if ((r = av_add_index_entry(st, framepos, i * (int64_t)c->frame_size, size, 0,
125                                     AVINDEX_KEYFRAME)) < 0)
126             return r;
127         framepos += size;
128     }
129     crc = ffio_get_checksum(s->pb) ^ UINT32_MAX;
130     if (crc != avio_rl32(s->pb) && s->error_recognition & AV_EF_CRCCHECK) {
131         av_log(s, AV_LOG_ERROR, "Seek table CRC error\n");
132         return AVERROR_INVALIDDATA;
133     }
134 
135     st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
136     st->codecpar->codec_id = AV_CODEC_ID_TTA;
137     st->codecpar->channels = channels;
138     st->codecpar->sample_rate = samplerate;
139     st->codecpar->bits_per_coded_sample = bps;
140 
141     if (s->pb->seekable & AVIO_SEEKABLE_NORMAL) {
142         int64_t pos = avio_tell(s->pb);
143         ff_ape_parse_tag(s);
144         avio_seek(s->pb, pos, SEEK_SET);
145     }
146 
147     return 0;
148 }
149 
tta_read_packet(AVFormatContext * s,AVPacket * pkt)150 static int tta_read_packet(AVFormatContext *s, AVPacket *pkt)
151 {
152     TTAContext *c = s->priv_data;
153     AVStream *st = s->streams[0];
154     int size, ret;
155 
156     // FIXME!
157     if (c->currentframe >= c->totalframes)
158         return AVERROR_EOF;
159 
160     if (st->nb_index_entries < c->totalframes) {
161         av_log(s, AV_LOG_ERROR, "Index entry disappeared\n");
162         return AVERROR_INVALIDDATA;
163     }
164 
165     size = st->index_entries[c->currentframe].size;
166 
167     ret = av_get_packet(s->pb, pkt, size);
168     pkt->dts = st->index_entries[c->currentframe++].timestamp;
169     pkt->duration = c->currentframe == c->totalframes ? c->last_frame_size :
170                                                         c->frame_size;
171     return ret;
172 }
173 
tta_read_seek(AVFormatContext * s,int stream_index,int64_t timestamp,int flags)174 static int tta_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
175 {
176     TTAContext *c = s->priv_data;
177     AVStream *st = s->streams[stream_index];
178     int index = av_index_search_timestamp(st, timestamp, flags);
179     if (index < 0)
180         return -1;
181     if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
182         return -1;
183 
184     c->currentframe = index;
185 
186     return 0;
187 }
188 
189 AVInputFormat ff_tta_demuxer = {
190     .name           = "tta",
191     .long_name      = NULL_IF_CONFIG_SMALL("TTA (True Audio)"),
192     .priv_data_size = sizeof(TTAContext),
193     .read_probe     = tta_probe,
194     .read_header    = tta_read_header,
195     .read_packet    = tta_read_packet,
196     .read_seek      = tta_read_seek,
197     .extensions     = "tta",
198 };
199