2 * Copyright (C) 2006-2007 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 * based in parts on libfaad, Copyright (C) 2003-2005 M. Bakker,
11 /** \file aac_afh.c para_server's aac audio format handler */
21 static int aac_find_stsz(unsigned char *buf
, size_t buflen
, off_t
*skip
)
25 for (i
= 0; i
+ 16 < buflen
; i
++) {
26 unsigned char *p
= buf
+ i
;
27 unsigned sample_count
, sample_size
;
29 if (p
[0] != 's' || p
[1] != 't' || p
[2] != 's' || p
[3] != 'z')
31 PARA_DEBUG_LOG("found stsz@%d\n", i
);
33 sample_size
= aac_read_int32(buf
+ i
);
34 PARA_DEBUG_LOG("sample size: %d\n", sample_size
);
36 sample_count
= aac_read_int32(buf
+ i
);
38 PARA_DEBUG_LOG("sample count: %d\n", sample_count
);
45 static ssize_t
aac_compute_chunk_table(struct afh_info
*afhi
,
46 unsigned char *map
, size_t numbytes
)
52 ret
= aac_find_stsz(map
, numbytes
, &skip
);
55 afhi
->chunks_total
= ret
;
56 PARA_DEBUG_LOG("sz table has %lu entries\n", afhi
->chunks_total
);
57 afhi
->chunk_table
= para_malloc((afhi
->chunks_total
+ 1) * sizeof(size_t));
58 for (i
= 1; i
<= afhi
->chunks_total
; i
++) {
59 if (skip
+ 4 > numbytes
)
61 sum
+= aac_read_int32(map
+ skip
);
62 afhi
->chunk_table
[i
] = sum
;
64 // if (i < 10 || i + 10 > afhi->chunks_total)
65 // PARA_DEBUG_LOG("offset #%d: %zu\n", i, afhi->chunk_table[i]);
70 static int aac_set_chunk_tv(struct afh_info
*afhi
,
71 mp4AudioSpecificConfig
*mp4ASC
, long unsigned *seconds
)
73 float tmp
= mp4ASC
->sbr_present_flag
== 1? 2047 : 1023;
75 long unsigned ms
= 1000.0 * afhi
->chunks_total
* tmp
76 / mp4ASC
->samplingFrequency
;
78 if (!mp4ASC
->samplingFrequency
)
80 ms
= 1000.0 * afhi
->chunks_total
* tmp
/ mp4ASC
->samplingFrequency
;
82 tv_divide(afhi
->chunks_total
, &total
, &afhi
->chunk_tv
);
83 PARA_INFO_LOG("%luHz, %lus (%lu x %lums)\n",
84 mp4ASC
->samplingFrequency
, ms
/ 1000,
85 afhi
->chunks_total
, tv2ms(&afhi
->chunk_tv
));
93 * Init m4a file and write some tech data to given pointers.
95 static int aac_get_file_info(char *map
, size_t numbytes
,
96 struct afh_info
*afhi
)
101 unsigned long rate
= 0, decoder_len
;
102 unsigned char channels
= 0;
103 mp4AudioSpecificConfig mp4ASC
;
104 NeAACDecHandle handle
= NULL
;
105 unsigned char *umap
= (unsigned char *) map
;
107 ret
= aac_find_esds(umap
, numbytes
, &skip
, &decoder_len
);
111 ret
= -E_AAC_AFH_INIT
;
112 if (NeAACDecInit(handle
, umap
+ skip
, decoder_len
, &rate
, &channels
))
116 PARA_DEBUG_LOG("rate: %lu, channels: %d\n", rate
, channels
);
118 if (NeAACDecAudioSpecificConfig(umap
+ skip
, numbytes
- skip
, &mp4ASC
))
120 if (!mp4ASC
.samplingFrequency
)
122 ret
= aac_compute_chunk_table(afhi
, umap
, numbytes
);
126 ret
= aac_set_chunk_tv(afhi
, &mp4ASC
, &afhi
->seconds_total
);
129 ret
= aac_find_entry_point(umap
+ skip
, numbytes
- skip
, &skip
);
132 afhi
->chunk_table
[0] = ret
;
133 for (i
= 1; i
<= afhi
->chunks_total
; i
++)
134 afhi
->chunk_table
[i
] += ret
;
135 afhi
->channels
= channels
;
136 afhi
->frequency
= rate
;
137 ret
= (afhi
->chunk_table
[afhi
->chunks_total
] - afhi
->chunk_table
[0]) * 8; /* bits */
138 ret
+= (channels
* afhi
->seconds_total
* 500); /* avoid rounding error */
139 afhi
->bitrate
= ret
/ (channels
* afhi
->seconds_total
* 1000);
140 sprintf(afhi
->info_string
, "%s:\n%s:\n%s:\n",
141 status_item_list
[SI_AUDIO_FILE_INFO
],
142 status_item_list
[SI_TAGINFO1
],
143 status_item_list
[SI_TAGINFO2
]
145 tv_scale(20, &afhi
->chunk_tv
, &afhi
->eof_tv
);
149 NeAACDecClose(handle
);
153 static const char* aac_suffixes
[] = {"m4a", "mp4", NULL
};
155 * the init function of the aac audio format handler
157 * \param afh pointer to the struct to initialize
159 void aac_afh_init(struct audio_format_handler
*afh
)
161 afh
->get_file_info
= aac_get_file_info
,
162 afh
->suffixes
= aac_suffixes
;