2 * Copyright (C) 2006-2007 Andre Noll <maan@systemlinux.org>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
19 * based in parts on libfaad, Copyright (C) 2003-2005 M. Bakker,
23 /** \file aac_afh.c para_server's aac audio format handler */
31 static int aac_find_stsz(unsigned char *buf
, off_t buflen
, off_t
*skip
)
35 for (i
= 0; i
+ 16 < buflen
; i
++) {
36 unsigned char *p
= buf
+ i
;
37 unsigned sample_count
, sample_size
;
39 if (p
[0] != 's' || p
[1] != 't' || p
[2] != 's' || p
[3] != 'z')
41 PARA_INFO_LOG("found stsz@%d\n", i
);
43 sample_size
= aac_read_int32(buf
+ i
);
44 PARA_INFO_LOG("sample size: %d\n", sample_size
);
46 sample_count
= aac_read_int32(buf
+ i
);
48 PARA_INFO_LOG("sample count: %d\n", sample_count
);
55 static ssize_t
aac_compute_chunk_table(struct audio_format_info
*afi
,
56 unsigned char *map
, off_t numbytes
)
62 ret
= aac_find_stsz(map
, numbytes
, &skip
);
65 afi
->chunks_total
= ret
;
66 PARA_INFO_LOG("sz table has %lu entries\n", afi
->chunks_total
);
67 afi
->chunk_table
= para_malloc((afi
->chunks_total
+ 1) * sizeof(size_t));
68 for (i
= 1; i
<= afi
->chunks_total
; i
++) {
69 if (skip
+ 4 > numbytes
)
71 sum
+= aac_read_int32(map
+ skip
);
72 afi
->chunk_table
[i
] = sum
;
74 // if (i < 10 || i + 10 > afi->chunks_total)
75 // PARA_DEBUG_LOG("offset #%d: %zu\n", i, afi->chunk_table[i]);
80 static long unsigned aac_set_chunk_tv(struct audio_format_info
*afi
,
81 mp4AudioSpecificConfig
*mp4ASC
)
83 float tmp
= mp4ASC
->sbr_present_flag
== 1? 2047 : 1023,
84 ms
= 1000.0 * afi
->chunks_total
* tmp
/ mp4ASC
->samplingFrequency
;
88 tv_divide(afi
->chunks_total
, &total
, &afi
->chunk_tv
);
89 PARA_INFO_LOG("%luHz, %fs (%lu x %lums)\n",
90 mp4ASC
->samplingFrequency
, ms
/ 1000,
91 afi
->chunks_total
, tv2ms(&afi
->chunk_tv
));
92 return ms
< 1000? -E_MP4ASC
: ms
/ 1000;
96 * Init m4a file and write some tech data to given pointers.
98 static int aac_get_file_info(char *map
, off_t numbytes
,
99 struct audio_format_info
*afi
)
104 unsigned long rate
= 0, decoder_len
;
105 unsigned char channels
= 0;
106 mp4AudioSpecificConfig mp4ASC
;
107 NeAACDecHandle handle
;
109 ret
= aac_find_esds(map
, numbytes
, &skip
);
114 ret
= -E_AACDEC_INIT
;
115 if (NeAACDecInit(handle
, map
+ skip
, decoder_len
, &rate
, &channels
))
119 PARA_INFO_LOG("rate: %lu, channels: %d\n", rate
, channels
);
121 if (NeAACDecAudioSpecificConfig(map
+ skip
, numbytes
- skip
, &mp4ASC
))
123 if (!mp4ASC
.samplingFrequency
)
125 ret
= aac_compute_chunk_table(afi
, map
, numbytes
);
129 afi
->seconds_total
= aac_set_chunk_tv(afi
, &mp4ASC
);
130 ret
= aac_find_entry_point(map
+ skip
, numbytes
- skip
, &skip
);
133 afi
->chunk_table
[0] = ret
;
134 for (i
= 1; i
<= afi
->chunks_total
; i
++)
135 afi
->chunk_table
[i
] += ret
;
136 afi
->channels
= channels
;
137 afi
->frequency
= rate
;
138 ret
= (afi
->chunk_table
[afi
->chunks_total
] - afi
->chunk_table
[0]) * 8; /* bits */
139 ret
+= (channels
* afi
->seconds_total
* 500); /* avoid rounding error */
140 afi
->bitrate
= ret
/ (channels
* afi
->seconds_total
* 1000);
141 sprintf(afi
->info_string
, "audio_file_info1:%lu x %lums, "
142 "%uHz, %d channel%s, %ukb/s\n"
143 "audio_file_info2:\n"
144 "audio_file_info3:\n",
145 afi
->chunks_total
, tv2ms(&afi
->chunk_tv
),
146 afi
->frequency
, channels
, channels
== 1? "" : "s", afi
->bitrate
148 tv_scale(20, &afi
->chunk_tv
, &afi
->eof_tv
);
154 static const char* aac_suffixes
[] = {"m4a", "mp4", NULL
};
156 * the init function of the aac audio format handler
158 * \param afh pointer to the struct to initialize
160 void aac_afh_init(struct audio_format_handler
*afh
)
162 afh
->get_file_info
= aac_get_file_info
,
163 afh
->suffixes
= aac_suffixes
;