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 */
25 #include "server.cmdline.h"
33 static int aac_find_stsz(unsigned char *buf
, off_t buflen
, off_t
*skip
)
37 for (i
= 0; i
+ 16 < buflen
; i
++) {
38 unsigned char *p
= buf
+ i
;
39 unsigned sample_count
, sample_size
;
41 if (p
[0] != 's' || p
[1] != 't' || p
[2] != 's' || p
[3] != 'z')
43 PARA_INFO_LOG("found stsz@%d\n", i
);
45 sample_size
= aac_read_int32(buf
+ i
);
46 PARA_INFO_LOG("sample size: %d\n", sample_size
);
48 sample_count
= aac_read_int32(buf
+ i
);
50 PARA_INFO_LOG("sample count: %d\n", sample_count
);
57 static ssize_t
aac_compute_chunk_table(struct audio_format_info
*afi
,
58 unsigned char *map
, off_t numbytes
)
64 ret
= aac_find_stsz(map
, numbytes
, &skip
);
67 afi
->chunks_total
= ret
;
68 PARA_INFO_LOG("sz table has %lu entries\n", afi
->chunks_total
);
69 afi
->chunk_table
= para_malloc((afi
->chunks_total
+ 1) * sizeof(size_t));
70 for (i
= 1; i
<= afi
->chunks_total
; i
++) {
71 if (skip
+ 4 > numbytes
)
73 sum
+= aac_read_int32(map
+ skip
);
74 afi
->chunk_table
[i
] = sum
;
76 // if (i < 10 || i + 10 > afi->chunks_total)
77 // PARA_DEBUG_LOG("offset #%d: %zu\n", i, afi->chunk_table[i]);
82 static long unsigned aac_set_chunk_tv(struct audio_format_info
*afi
,
83 mp4AudioSpecificConfig
*mp4ASC
)
85 float tmp
= mp4ASC
->sbr_present_flag
== 1? 2047 : 1023,
86 ms
= 1000.0 * afi
->chunks_total
* tmp
/ mp4ASC
->samplingFrequency
;
90 tv_divide(afi
->chunks_total
, &total
, &afi
->chunk_tv
);
91 PARA_INFO_LOG("%luHz, %fs (%lu x %lums)\n",
92 mp4ASC
->samplingFrequency
, ms
/ 1000,
93 afi
->chunks_total
, tv2ms(&afi
->chunk_tv
));
94 return ms
< 1000? -E_MP4ASC
: ms
/ 1000;
98 * Init m4a file and write some tech data to given pointers.
100 static int aac_get_file_info(char *map
, off_t numbytes
,
101 struct audio_format_info
*afi
)
106 unsigned long rate
= 0, decoder_len
;
107 unsigned char channels
= 0;
108 mp4AudioSpecificConfig mp4ASC
;
109 NeAACDecHandle handle
;
111 ret
= aac_find_esds(map
, numbytes
, &skip
);
116 ret
= -E_AACDEC_INIT
;
117 if (NeAACDecInit(handle
, map
+ skip
, decoder_len
, &rate
, &channels
))
121 PARA_INFO_LOG("rate: %lu, channels: %d\n", rate
, channels
);
123 if (NeAACDecAudioSpecificConfig(map
+ skip
, numbytes
- skip
, &mp4ASC
))
125 if (!mp4ASC
.samplingFrequency
)
127 ret
= aac_compute_chunk_table(afi
, map
, numbytes
);
131 afi
->seconds_total
= aac_set_chunk_tv(afi
, &mp4ASC
);
132 ret
= aac_find_entry_point(map
+ skip
, numbytes
- skip
, &skip
);
135 afi
->chunk_table
[0] = ret
;
136 for (i
= 1; i
<= afi
->chunks_total
; i
++)
137 afi
->chunk_table
[i
] += ret
;
138 afi
->channels
= channels
;
139 afi
->frequency
= rate
;
140 ret
= (afi
->chunk_table
[afi
->chunks_total
] - afi
->chunk_table
[0]) * 8; /* bits */
141 ret
+= (channels
* afi
->seconds_total
* 500); /* avoid rounding error */
142 afi
->bitrate
= ret
/ (channels
* afi
->seconds_total
* 1000);
143 sprintf(afi
->info_string
, "audio_file_info1:%lu x %lums, "
144 "%uHz, %d channel%s, %ukb/s\n"
145 "audio_file_info2:\n"
146 "audio_file_info3:\n",
147 afi
->chunks_total
, tv2ms(&afi
->chunk_tv
),
148 afi
->frequency
, channels
, channels
== 1? "" : "s", afi
->bitrate
150 tv_scale(20, &afi
->chunk_tv
, &afi
->eof_tv
);
156 static const char* aac_suffixes
[] = {"m4a", "mp4", NULL
};
158 * the init function of the aac audio format handler
160 * \param afh pointer to the struct to initialize
162 void aac_afh_init(struct audio_format_handler
*afh
)
164 afh
->get_file_info
= aac_get_file_info
,
165 afh
->suffixes
= aac_suffixes
;