3 * Copyright (c) 2006 Alex Beregszaszi
5 * This file is part of FFmpeg.
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.
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.
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
22 #include "libavcodec/get_bits.h"
25 #include "avio_internal.h"
28 #include "libavutil/crc.h"
29 #include "libavutil/dict.h"
32 int totalframes
, currentframe
;
37 static unsigned long tta_check_crc(unsigned long checksum
, const uint8_t *buf
,
40 return av_crc(av_crc_get_table(AV_CRC_32_IEEE_LE
), checksum
, buf
, len
);
43 static int tta_probe(AVProbeData
*p
)
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;
54 static int tta_read_header(AVFormatContext
*s
)
56 TTAContext
*c
= s
->priv_data
;
58 int i
, channels
, bps
, samplerate
;
59 uint64_t framepos
, start_offset
;
60 uint32_t nb_samples
, crc
;
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
;
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
;
78 nb_samples
= avio_rl32(s
->pb
);
80 av_log(s
, AV_LOG_ERROR
, "invalid number of samples\n");
81 return AVERROR_INVALIDDATA
;
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
;
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
);
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
;
102 st
= avformat_new_stream(s
, NULL
);
104 return AVERROR(ENOMEM
);
106 avpriv_set_pts_info(st
, 64, 1, samplerate
);
108 st
->duration
= nb_samples
;
110 framepos
= avio_tell(s
->pb
) + 4*c
->totalframes
+ 4;
112 if (ff_alloc_extradata(st
->codec
, avio_tell(s
->pb
) - start_offset
))
113 return AVERROR(ENOMEM
);
115 avio_seek(s
->pb
, start_offset
, SEEK_SET
);
116 avio_read(s
->pb
, st
->codec
->extradata
, st
->codec
->extradata_size
);
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,
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
;
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
;
137 if (s
->pb
->seekable
) {
138 int64_t pos
= avio_tell(s
->pb
);
140 avio_seek(s
->pb
, pos
, SEEK_SET
);
146 static int tta_read_packet(AVFormatContext
*s
, AVPacket
*pkt
)
148 TTAContext
*c
= s
->priv_data
;
149 AVStream
*st
= s
->streams
[0];
153 if (c
->currentframe
>= c
->totalframes
)
156 size
= st
->index_entries
[c
->currentframe
].size
;
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
:
165 static int tta_read_seek(AVFormatContext
*s
, int stream_index
, int64_t timestamp
, int flags
)
167 TTAContext
*c
= s
->priv_data
;
168 AVStream
*st
= s
->streams
[stream_index
];
169 int index
= av_index_search_timestamp(st
, timestamp
, flags
);
172 if (avio_seek(s
->pb
, st
->index_entries
[index
].pos
, SEEK_SET
) < 0)
175 c
->currentframe
= index
;
180 AVInputFormat ff_tta_demuxer
= {
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
,