2 * Copyright (C) 2006-2008 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 int atom_cmp(unsigned char *buf1
, char *buf2
)
47 unsigned char *b2
= (unsigned char *)buf2
;
60 static int read_atom_header(unsigned char *buf
, uint64_t *subsize
, unsigned char type
[5])
63 uint64_t size
= (buf
[0] << 24) + (buf
[1] << 16) + (buf
[2] << 8) + buf
[3];
65 memcpy(type
, buf
+ 4, 4);
68 PARA_DEBUG_LOG("size: %llu, type: %s\n", (long long unsigned)size
, type
);
75 for (i
= 0; i
< 8; i
++)
76 size
|= ((uint64_t)buf
[i
]) << ((7 - i
) * 8);
81 static char *get_tag(unsigned char *p
, int size
)
86 buf
= para_malloc(size
+ 1);
90 PARA_DEBUG_LOG("size: %d: %s\n", size
, buf
);
94 static char *read_tags(unsigned char *buf
, size_t buflen
)
96 unsigned char *p
= buf
;
97 char *title
= NULL
, *artist
= NULL
, *album
= NULL
, *year
= NULL
,
98 *comment
= NULL
, *result
;
100 while (p
+ 32 < buf
+ buflen
) {
101 unsigned char *q
, type1
[5], type2
[5];
102 uint64_t size1
, size2
;
105 ret
= read_atom_header(p
, &size1
, type1
);
106 ret2
= read_atom_header(p
+ ret
, &size2
, type2
);
108 if (size2
<= 16 || atom_cmp(type2
, "data")) {
113 q
= p
+ ret
+ ret2
+ 8;
114 if (q
+ size2
> buf
+ buflen
)
116 if (!atom_cmp(type1
, "©ART"))
117 artist
= get_tag(q
, size2
);
118 else if (!atom_cmp(type1
, "©alb"))
119 album
= get_tag(q
, size2
);
120 else if (!atom_cmp(type1
, "©nam"))
121 title
= get_tag(q
, size2
);
122 else if (!atom_cmp(type1
, "©cmt"))
123 comment
= get_tag(q
, size2
);
124 else if (!atom_cmp(type1
, "©day"))
125 year
= get_tag(q
, size2
);
128 result
= make_taginfo(title
, artist
, album
, year
, comment
);
137 static char *read_meta(unsigned char *buf
, size_t buflen
)
139 unsigned char *p
= buf
;
141 while (p
+ 4 < buf
+ buflen
) {
143 if (p
[0] != 'i' || p
[1] != 'l' || p
[2] != 's' || p
[3] != 't') {
148 return read_tags(p
, buflen
- (p
- buf
));
150 return make_taginfo(NULL
, NULL
, NULL
, NULL
, NULL
);
153 static char *aac_get_taginfo(unsigned char *buf
, size_t buflen
)
157 unsigned char type
[5];
159 for (i
= 0; i
+ 24 < buflen
; i
++) {
160 unsigned char *p
= buf
+ i
;
161 if (p
[0] != 'm' || p
[1] != 'e' || p
[2] != 't' || p
[3] != 'a')
163 PARA_INFO_LOG("found metadata at offset %d\n", i
);
166 i
+= read_atom_header(p
, &subsize
, type
);
168 return read_meta(p
, buflen
- i
);
170 PARA_INFO_LOG("no meta data\n");
171 return make_taginfo(NULL
, NULL
, NULL
, NULL
, NULL
);
174 static ssize_t
aac_compute_chunk_table(struct afh_info
*afhi
,
175 unsigned char *map
, size_t numbytes
)
181 ret
= aac_find_stsz(map
, numbytes
, &skip
);
184 afhi
->chunks_total
= ret
;
185 PARA_DEBUG_LOG("sz table has %lu entries\n", afhi
->chunks_total
);
186 afhi
->chunk_table
= para_malloc((afhi
->chunks_total
+ 1) * sizeof(size_t));
187 for (i
= 1; i
<= afhi
->chunks_total
; i
++) {
188 if (skip
+ 4 > numbytes
)
190 sum
+= aac_read_int32(map
+ skip
);
191 afhi
->chunk_table
[i
] = sum
;
193 // if (i < 10 || i + 10 > afhi->chunks_total)
194 // PARA_DEBUG_LOG("offset #%d: %zu\n", i, afhi->chunk_table[i]);
199 static int aac_set_chunk_tv(struct afh_info
*afhi
,
200 mp4AudioSpecificConfig
*mp4ASC
, long unsigned *seconds
)
202 float tmp
= mp4ASC
->sbr_present_flag
== 1? 2047 : 1023;
203 struct timeval total
;
204 long unsigned ms
= 1000.0 * afhi
->chunks_total
* tmp
205 / mp4ASC
->samplingFrequency
;
207 if (!mp4ASC
->samplingFrequency
)
209 ms
= 1000.0 * afhi
->chunks_total
* tmp
/ mp4ASC
->samplingFrequency
;
211 tv_divide(afhi
->chunks_total
, &total
, &afhi
->chunk_tv
);
212 PARA_INFO_LOG("%luHz, %lus (%lu x %lums)\n",
213 mp4ASC
->samplingFrequency
, ms
/ 1000,
214 afhi
->chunks_total
, tv2ms(&afhi
->chunk_tv
));
217 *seconds
= ms
/ 1000;
222 * Init m4a file and write some tech data to given pointers.
224 static int aac_get_file_info(char *map
, size_t numbytes
, __a_unused
int fd
,
225 struct afh_info
*afhi
)
230 unsigned long rate
= 0, decoder_len
;
231 unsigned char channels
= 0;
232 mp4AudioSpecificConfig mp4ASC
;
233 NeAACDecHandle handle
= NULL
;
234 unsigned char *umap
= (unsigned char *) map
;
237 ret
= aac_find_esds(umap
, numbytes
, &skip
, &decoder_len
);
240 taginfo
= aac_get_taginfo(umap
, numbytes
);
242 ret
= -E_AAC_AFH_INIT
;
243 if (NeAACDecInit(handle
, umap
+ skip
, decoder_len
, &rate
, &channels
))
247 PARA_DEBUG_LOG("rate: %lu, channels: %d\n", rate
, channels
);
249 if (NeAACDecAudioSpecificConfig(umap
+ skip
, numbytes
- skip
, &mp4ASC
))
251 if (!mp4ASC
.samplingFrequency
)
253 ret
= aac_compute_chunk_table(afhi
, umap
, numbytes
);
257 ret
= aac_set_chunk_tv(afhi
, &mp4ASC
, &afhi
->seconds_total
);
260 ret
= aac_find_entry_point(umap
+ skip
, numbytes
- skip
, &skip
);
263 afhi
->chunk_table
[0] = ret
;
264 for (i
= 1; i
<= afhi
->chunks_total
; i
++)
265 afhi
->chunk_table
[i
] += ret
;
266 afhi
->channels
= channels
;
267 afhi
->frequency
= rate
;
268 ret
= (afhi
->chunk_table
[afhi
->chunks_total
] - afhi
->chunk_table
[0]) * 8; /* bits */
269 ret
+= (channels
* afhi
->seconds_total
* 500); /* avoid rounding error */
270 afhi
->bitrate
= ret
/ (channels
* afhi
->seconds_total
* 1000);
271 afhi
->info_string
= make_message("%s:\n%s",
272 status_item_list
[SI_AUDIO_FILE_INFO
],
275 tv_scale(20, &afhi
->chunk_tv
, &afhi
->eof_tv
);
279 NeAACDecClose(handle
);
283 static const char* aac_suffixes
[] = {"m4a", "mp4", NULL
};
285 * the init function of the aac audio format handler
287 * \param afh pointer to the struct to initialize
289 void aac_afh_init(struct audio_format_handler
*afh
)
291 afh
->get_file_info
= aac_get_file_info
,
292 afh
->suffixes
= aac_suffixes
;