The mp4 tagger.
[paraslash.git] / aac_afh.c
1 /*
2 * Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6 /*
7 * based in parts on libfaad, Copyright (C) 2003-2005 M. Bakker,
8 * Ahead Software AG
9 */
10
11 /** \file aac_afh.c para_server's aac audio format handler. */
12
13 #include <regex.h>
14 #include <mp4v2/mp4v2.h>
15
16 #include "para.h"
17 #include "error.h"
18 #include "afh.h"
19 #include "string.h"
20 #include "aac.h"
21 #include "fd.h"
22
23 static int aac_find_stsz(unsigned char *buf, size_t buflen, off_t *skip)
24 {
25 int i;
26
27 for (i = 0; i + 16 < buflen; i++) {
28 unsigned char *p = buf + i;
29 unsigned sample_count, sample_size;
30
31 if (p[0] != 's' || p[1] != 't' || p[2] != 's' || p[3] != 'z')
32 continue;
33 PARA_DEBUG_LOG("found stsz@%d\n", i);
34 i += 8;
35 sample_size = aac_read_int32(buf + i);
36 PARA_DEBUG_LOG("sample size: %d\n", sample_size);
37 i += 4;
38 sample_count = aac_read_int32(buf + i);
39 i += 4;
40 PARA_DEBUG_LOG("sample count: %d\n", sample_count);
41 *skip = i;
42 return sample_count;
43 }
44 return -E_STSZ;
45 }
46
47 static int atom_cmp(const unsigned char *buf1, const char *buf2)
48 {
49 const unsigned char *b2 = (unsigned char *)buf2;
50
51 if (buf1[0] != b2[0])
52 return 1;
53 if (buf1[1] != b2[1])
54 return 1;
55 if (buf1[2] != b2[2])
56 return 1;
57 if (buf1[3] != b2[3])
58 return 1;
59 return 0;
60 }
61
62 static int read_atom_header(unsigned char *buf, uint64_t *subsize, unsigned char type[5])
63 {
64 int i;
65 uint64_t size = (buf[0] << 24) + (buf[1] << 16) + (buf[2] << 8) + buf[3];
66
67 memcpy(type, buf + 4, 4);
68 type[4] = '\0';
69
70 PARA_DEBUG_LOG("size: %llu, type: %s\n", (long long unsigned)size, type);
71 if (size != 1) {
72 *subsize = size;
73 return 8;
74 }
75 buf += 4;
76 size = 0;
77 for (i = 0; i < 8; i++)
78 size |= ((uint64_t)buf[i]) << ((7 - i) * 8);
79 *subsize = size;
80 return 16;
81 }
82
83 static char *get_tag(unsigned char *p, int size)
84 {
85 char *buf;
86
87 assert(size > 0);
88 buf = para_malloc(size + 1);
89
90 memcpy(buf, p, size);
91 buf[size] = '\0';
92 PARA_DEBUG_LOG("size: %d: %s\n", size, buf);
93 return buf;
94 }
95
96 static void read_tags(unsigned char *buf, size_t buflen, struct afh_info *afhi)
97 {
98 unsigned char *p = buf;
99
100 while (p + 32 < buf + buflen) {
101 unsigned char *q, type1[5], type2[5];
102 uint64_t size1, size2;
103 int ret, ret2;
104
105 ret = read_atom_header(p, &size1, type1);
106 ret2 = read_atom_header(p + ret, &size2, type2);
107
108 if (size2 <= 16 || atom_cmp(type2, "data")) {
109 p += size1;
110 continue;
111 }
112 size2 -= 16;
113 q = p + ret + ret2 + 8;
114 if (q + size2 > buf + buflen)
115 break;
116 if (!atom_cmp(type1, "\xa9" "ART"))
117 afhi->tags.artist = get_tag(q, size2);
118 else if (!atom_cmp(type1, "\xa9" "alb"))
119 afhi->tags.album = get_tag(q, size2);
120 else if (!atom_cmp(type1, "\xa9" "nam"))
121 afhi->tags.title = get_tag(q, size2);
122 else if (!atom_cmp(type1, "\xa9" "cmt"))
123 afhi->tags.comment = get_tag(q, size2);
124 else if (!atom_cmp(type1, "\xa9" "day"))
125 afhi->tags.year = get_tag(q, size2);
126 p += size1;
127 }
128 }
129
130 static void read_meta(unsigned char *buf, size_t buflen, struct afh_info *afhi)
131 {
132 unsigned char *p = buf;
133
134 while (p + 4 < buf + buflen) {
135
136 if (p[0] != 'i' || p[1] != 'l' || p[2] != 's' || p[3] != 't') {
137 p++;
138 continue;
139 }
140 p += 4;
141 return read_tags(p, buflen - (p - buf), afhi);
142 }
143 }
144
145 static void aac_get_taginfo(unsigned char *buf, size_t buflen,
146 struct afh_info *afhi)
147 {
148 int i;
149 uint64_t subsize;
150 unsigned char type[5];
151
152 for (i = 0; i + 24 < buflen; i++) {
153 unsigned char *p = buf + i;
154 if (p[0] != 'm' || p[1] != 'e' || p[2] != 't' || p[3] != 'a')
155 continue;
156 PARA_INFO_LOG("found metadata at offset %d\n", i);
157 i += 8;
158 p = buf + i;
159 i += read_atom_header(p, &subsize, type);
160 p = buf + i;
161 return read_meta(p, buflen - i, afhi);
162 }
163 PARA_INFO_LOG("no meta data\n");
164 }
165
166 static ssize_t aac_compute_chunk_table(struct afh_info *afhi,
167 unsigned char *map, size_t numbytes)
168 {
169 int ret, i;
170 size_t sum = 0;
171 off_t skip;
172
173 ret = aac_find_stsz(map, numbytes, &skip);
174 if (ret < 0)
175 return ret;
176 afhi->chunks_total = ret;
177 PARA_DEBUG_LOG("sz table has %lu entries\n", afhi->chunks_total);
178 afhi->chunk_table = para_malloc((afhi->chunks_total + 1) * sizeof(size_t));
179 for (i = 1; i <= afhi->chunks_total; i++) {
180 if (skip + 4 > numbytes)
181 break;
182 sum += aac_read_int32(map + skip);
183 afhi->chunk_table[i] = sum;
184 skip += 4;
185 // if (i < 10 || i + 10 > afhi->chunks_total)
186 // PARA_DEBUG_LOG("offset #%d: %zu\n", i, afhi->chunk_table[i]);
187 }
188 return skip;
189 }
190
191 static int aac_set_chunk_tv(struct afh_info *afhi,
192 mp4AudioSpecificConfig *mp4ASC, long unsigned *seconds)
193 {
194 float tmp = mp4ASC->sbr_present_flag == 1? 2047 : 1023;
195 struct timeval total;
196 long unsigned ms;
197
198 if (!mp4ASC->samplingFrequency)
199 return -E_MP4ASC;
200 ms = 1000.0 * afhi->chunks_total * tmp / mp4ASC->samplingFrequency;
201 ms2tv(ms, &total);
202 tv_divide(afhi->chunks_total, &total, &afhi->chunk_tv);
203 PARA_INFO_LOG("%luHz, %lus (%lu x %lums)\n",
204 mp4ASC->samplingFrequency, ms / 1000,
205 afhi->chunks_total, tv2ms(&afhi->chunk_tv));
206 if (ms < 1000)
207 return -E_MP4ASC;
208 *seconds = ms / 1000;
209 return 1;
210 }
211
212 /*
213 * Init m4a file and write some tech data to given pointers.
214 */
215 static int aac_get_file_info(char *map, size_t numbytes, __a_unused int fd,
216 struct afh_info *afhi)
217 {
218 int i;
219 size_t skip;
220 ssize_t ret;
221 unsigned long rate = 0, decoder_len;
222 unsigned char channels = 0;
223 mp4AudioSpecificConfig mp4ASC;
224 NeAACDecHandle handle = NULL;
225 unsigned char *umap = (unsigned char *) map;
226
227 ret = aac_find_esds(umap, numbytes, &skip, &decoder_len);
228 if (ret < 0)
229 goto out;
230 aac_get_taginfo(umap, numbytes, afhi);
231 handle = aac_open();
232 ret = -E_AAC_AFH_INIT;
233 if (NeAACDecInit(handle, umap + skip, decoder_len, &rate, &channels))
234 goto out;
235 if (!channels)
236 goto out;
237 PARA_DEBUG_LOG("rate: %lu, channels: %d\n", rate, channels);
238 ret = -E_MP4ASC;
239 if (NeAACDecAudioSpecificConfig(umap + skip, numbytes - skip, &mp4ASC))
240 goto out;
241 if (!mp4ASC.samplingFrequency)
242 goto out;
243 ret = aac_compute_chunk_table(afhi, umap, numbytes);
244 if (ret < 0)
245 goto out;
246 skip = ret;
247 ret = aac_set_chunk_tv(afhi, &mp4ASC, &afhi->seconds_total);
248 if (ret < 0)
249 goto out;
250 ret = aac_find_entry_point(umap + skip, numbytes - skip, &skip);
251 if (ret < 0)
252 goto out;
253 afhi->chunk_table[0] = ret;
254 for (i = 1; i<= afhi->chunks_total; i++)
255 afhi->chunk_table[i] += ret;
256 afhi->channels = channels;
257 afhi->frequency = rate;
258 ret = (afhi->chunk_table[afhi->chunks_total] - afhi->chunk_table[0]) * 8; /* bits */
259 ret += (channels * afhi->seconds_total * 500); /* avoid rounding error */
260 afhi->bitrate = ret / (channels * afhi->seconds_total * 1000);
261 ret = 1;
262 out:
263 if (handle)
264 NeAACDecClose(handle);
265 return ret;
266 }
267
268 static int aac_rewrite_tags(const char *map, size_t mapsize,
269 struct taginfo *tags, int fd, const char *filename)
270 {
271 MP4FileHandle h;
272 const MP4Tags *mdata;
273 int ret = write_all(fd, map, mapsize);
274
275 if (ret < 0)
276 return ret;
277 lseek(fd, 0, SEEK_SET);
278 h = MP4Modify(filename, 0);
279 if (!h) {
280 PARA_ERROR_LOG("MP4Modify() failed, fd = %d\n", fd);
281 return -E_MP4V2;
282 }
283 mdata = MP4TagsAlloc();
284 assert(mdata);
285 if (!MP4TagsFetch(mdata, h)) {
286 PARA_ERROR_LOG("MP4Tags_Fetch() failed\n");
287 ret = -E_MP4V2;
288 goto close;
289 }
290
291 if (!MP4TagsSetAlbum(mdata, tags->album)) {
292 PARA_ERROR_LOG("Could not set album\n");
293 ret = -E_MP4V2;
294 goto tags_free;
295 }
296 if (!MP4TagsSetArtist(mdata, tags->artist)) {
297 PARA_ERROR_LOG("Could not set album\n");
298 ret = -E_MP4V2;
299 goto tags_free;
300 }
301 if (!MP4TagsSetComments(mdata, tags->comment)) {
302 PARA_ERROR_LOG("Could not set comment\n");
303 ret = -E_MP4V2;
304 goto tags_free;
305 }
306 if (!MP4TagsSetName(mdata, tags->title)) {
307 PARA_ERROR_LOG("Could not set title\n");
308 ret = -E_MP4V2;
309 goto tags_free;
310 }
311 if (!MP4TagsSetReleaseDate(mdata, tags->year)) {
312 PARA_ERROR_LOG("Could not set release date\n");
313 ret = -E_MP4V2;
314 goto tags_free;
315 }
316
317 if (!MP4TagsStore(mdata, h)) {
318 PARA_ERROR_LOG("Could not store tags\n");
319 ret = -E_MP4V2;
320 goto tags_free;
321 }
322 ret = 1;
323 tags_free:
324 MP4TagsFree(mdata);
325 close:
326 MP4Close(h, 0);
327 return ret;
328 }
329
330 static const char* aac_suffixes[] = {"m4a", "mp4", NULL};
331 /**
332 * the init function of the aac audio format handler
333 *
334 * \param afh pointer to the struct to initialize
335 */
336 void aac_afh_init(struct audio_format_handler *afh)
337 {
338 afh->get_file_info = aac_get_file_info,
339 afh->suffixes = aac_suffixes;
340 afh->rewrite_tags = aac_rewrite_tags;
341 }