2 * Copyright (C) 2003 Andre Noll <maan@tuebingen.mpg.de>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file mp3_afh.c para_server's mp3 audio format handler */
10 * This file is based in part on mp3tech.c and mp3tech.h, Copyright (C)
11 * 2000-2001 Cedric Tefft <cedric@earthling.net>, which in turn is based
14 * * MP3Info 0.5 by Ricardo Cerqueira <rmc@rccn.net>
15 * * MP3Stat 0.9 by Ed Sweetman <safemode@voicenet.com> and
16 * Johannes Overmann <overmann@iname.com>
27 * MIN_CONSEC_GOOD_FRAMES defines how many consecutive valid MP3 frames we need
28 * to see before we decide we are looking at a real MP3 file
30 #define MIN_CONSEC_GOOD_FRAMES 4
31 #define FRAME_HEADER_SIZE 4
32 #define MIN_FRAME_SIZE 21
43 unsigned int copyright;
44 unsigned int original;
45 unsigned int emphasis;
48 static const int frequencies[3][4] = {
49 {22050,24000,16000,50000}, /* MPEG 2.0 */
50 {44100,48000,32000,50000}, /* MPEG 1.0 */
51 {11025,12000,8000,50000} /* MPEG 2.5 */
54 static const int mp3info_bitrate[2][3][14] = {
56 {32,48,56,64,80,96,112,128,144,160,176,192,224,256}, /* layer 1 */
57 {8,16,24,32,40,48,56,64,80,96,112,128,144,160}, /* layer 2 */
58 {8,16,24,32,40,48,56,64,80,96,112,128,144,160} /* layer 3 */
62 {32,64,96,128,160,192,224,256,288,320,352,384,416,448}, /* layer 1 */
63 {32,48,56,64,80,96,112,128,160,192,224,256,320,384}, /* layer 2 */
64 {32,40,48,56,64,80,96,112,128,160,192,224,256,320} /* layer 3 */
68 static const int frame_size_index[] = {24000, 72000, 72000};
69 static const char *mode_text[] = {"stereo", "joint stereo", "dual channel", "mono", "invalid"};
75 static char *get_utf8(id3_ucs4_t const *string)
79 return (char *)id3_ucs4_utf8duplicate(string);
82 static char *get_stringlist(union id3_field *field)
84 unsigned int k, nstrings = id3_field_getnstrings(field);
87 for (k = 0; k < nstrings; k++) {
88 char *tmp = (char *)get_utf8(id3_field_getstrings(field, k));
91 result = make_message("%s %s", tmp2, tmp);
100 static char *get_string(union id3_field *field)
102 id3_ucs4_t const *string = id3_field_getfullstring(field);
104 return get_utf8(string);
107 #define FOR_EACH_FIELD(f, j, fr) for (j = 0; j < (fr)->nfields && \
108 (f = id3_frame_field((fr), j)); j++)
110 static char *get_strings(struct id3_frame *fr)
113 union id3_field *field;
115 FOR_EACH_FIELD(field, j, fr) {
116 enum id3_field_type type = id3_field_type(field);
118 if (type == ID3_FIELD_TYPE_STRINGLIST)
119 return get_stringlist(field);
120 if (type == ID3_FIELD_TYPE_STRINGFULL)
121 return get_string(field);
126 /* this only sets values which are undefined so far */
127 static void parse_frames(struct id3_tag *id3_t, struct taginfo *tags)
131 for (i = 0; i < id3_t->nframes; i++) {
132 struct id3_frame *fr = id3_t->frames[i];
133 if (!strcmp(fr->id, ID3_FRAME_TITLE)) {
135 tags->title = get_strings(fr);
138 if (!strcmp(fr->id, ID3_FRAME_ARTIST)) {
140 tags->artist = get_strings(fr);
143 if (!strcmp(fr->id, ID3_FRAME_ALBUM)) {
145 tags->album = get_strings(fr);
148 if (!strcmp(fr->id, ID3_FRAME_YEAR)) {
150 tags->year = get_strings(fr);
153 if (!strcmp(fr->id, ID3_FRAME_COMMENT)) {
155 tags->comment = get_strings(fr);
161 static int mp3_get_id3(unsigned char *map, size_t numbytes, __a_unused int fd,
162 struct taginfo *tags)
165 struct id3_tag *id3_t;
167 /* id3v2 tags are usually located at the beginning. */
168 id3_t = id3_tag_parse(map, numbytes);
170 parse_frames(id3_t, tags);
172 id3_tag_delete(id3_t);
174 /* Also look for an id3v1 tag at the end of the file. */
175 if (numbytes >= 128) {
176 id3_t = id3_tag_parse(map + numbytes - 128, 128);
178 parse_frames(id3_t, tags);
180 id3_tag_delete(id3_t);
186 #else /* HAVE_ID3TAG */
189 * Remove trailing whitespace from the end of a string
191 static char *unpad(char *string)
193 char *pos = string + strlen(string) - 1;
194 while (para_isspace(pos[0]))
199 static int mp3_get_id3(unsigned char *map, size_t numbytes, __a_unused int fd,
200 struct taginfo *tags)
202 char title[31], artist[31], album[31], year[5], comment[31];
205 if (numbytes < 128 || strncmp("TAG", (char *)map + numbytes - 128, 3)) {
206 PARA_DEBUG_LOG("no id3 v1 tag\n");
209 fpos = numbytes - 125;
210 memcpy(title, map + fpos, 30);
213 memcpy(artist, map + fpos, 30);
216 memcpy(album, map + fpos, 30);
219 memcpy(year, map + fpos, 4);
222 memcpy(comment, map + fpos, 30);
229 tags->artist = para_strdup(artist);
230 tags->title = para_strdup(title);
231 tags->year = para_strdup(year);
232 tags->album = para_strdup(album);
233 tags->comment = para_strdup(comment);
236 #endif /* HAVE_ID3TAG */
238 static int header_frequency(struct mp3header *h)
240 if (h->version > 2 || h->freq > 3)
241 return -E_HEADER_FREQ;
242 return frequencies[h->version][h->freq];
245 static const char *header_mode(struct mp3header *h)
248 h->mode = 4; /* invalid */
249 return mode_text[h->mode];
252 static int header_channels(struct mp3header *h)
261 static int header_bitrate(struct mp3header *h)
263 if (!h->layer || h->layer > 3 || h->bitrate > 14 || !h->bitrate)
264 return -E_HEADER_BITRATE;
265 return mp3info_bitrate[h->version & 1][3 - h->layer][h->bitrate - 1];
268 static int frame_length(struct mp3header *header)
270 int hb, hf = header_frequency(header);
274 hb = header_bitrate(header);
277 if (header->sync != 0xFFE || header->layer > 3)
279 return frame_size_index[3 - header->layer] *
280 ((header->version & 1) + 1) * hb / hf
284 static int compare_headers(struct mp3header *h1,struct mp3header *h2)
286 if ((*(unsigned int*)h1) == (*(unsigned int*)h2))
288 if ((h1->version == h2->version) &&
289 (h1->layer == h2->layer) &&
290 (h1->crc == h2->crc) &&
291 (h1->freq == h2->freq) &&
292 (h1->mode == h2->mode) &&
293 (h1->copyright == h2->copyright) &&
294 (h1->original == h2->original) &&
295 (h1->emphasis == h2->emphasis))
301 * get next MP3 frame header.
303 * On success, the header frame length is returned and the given header
304 * structure that is filled in. A return value of zero means that we did not
305 * retrieve a valid frame header, and a negative return value indicates an
308 static int get_header(unsigned char *map, size_t numbytes, off_t *fpos,
309 struct mp3header *header)
313 if (*fpos + FRAME_HEADER_SIZE > numbytes) {
314 *fpos = numbytes - 1;
318 header->layer = (map[*fpos + 1] >> 1) & 3;
319 header->sync = (((int)map[*fpos]<<4) | ((int)(map[*fpos + 1]&0xE0)>>4));
320 if (map[*fpos + 1] & 0x10)
321 header->version = (map[*fpos + 1] >> 3) & 1;
324 if ((header->sync != 0xFFE) || (header->layer != 1)) {
329 header->crc = map[*fpos + 1] & 1;
330 header->bitrate = (map[*fpos + 2] >> 4) & 0x0F;
331 header->freq = (map[*fpos + 2] >> 2) & 0x3;
332 header->padding = (map[*fpos + 2] >>1) & 0x1;
333 header->mode = (map[*fpos + 3] >> 6) & 0x3;
334 fl = frame_length(header);
335 ret = (fl >= MIN_FRAME_SIZE)? fl : -E_FRAME_LENGTH;
337 *fpos += FRAME_HEADER_SIZE;
342 * find the next mp3 header
344 * Return the length of the next frame header or zero if the end of the file is
347 static int mp3_seek_next_header(unsigned char *map, size_t numbytes, off_t *fpos,
348 struct mp3header *result)
350 int k, l = 0, first_len;
351 struct mp3header h, h2;
352 long valid_start = 0;
354 for (; *fpos < numbytes; (*fpos)++) {
355 if (map[*fpos] != 0xff)
358 first_len = get_header(map, numbytes, fpos, &h);
361 *fpos += first_len - FRAME_HEADER_SIZE;
362 for (k = 1; k < MIN_CONSEC_GOOD_FRAMES; k++) {
363 if ((l = get_header(map, numbytes, fpos, &h2)) <= 0)
365 if (!compare_headers(&h, &h2))
367 *fpos += l - FRAME_HEADER_SIZE;
369 if (k == MIN_CONSEC_GOOD_FRAMES) {
378 static int find_valid_start(unsigned char *map, size_t numbytes, off_t *fpos,
379 struct mp3header *header)
383 frame_len = get_header(map, numbytes, fpos, header);
387 frame_len = mp3_seek_next_header(map, numbytes, fpos, header);
391 *fpos -= FRAME_HEADER_SIZE;
393 return -E_FRAME_LENGTH;
397 static int mp3_read_info(unsigned char *map, size_t numbytes, int fd,
398 struct afh_info *afhi)
400 uint64_t freq_sum = 0, br_sum = 0;
401 int fl = 0, ret, len = 0, old_br = -1, vbr = 0;
402 struct timeval total_time = {0, 0};
403 unsigned chunk_table_size = 1000; /* gets increased on demand */
405 struct mp3header header;
406 const char *tag_versions[] = {"no", "id3v1", "id3v2", "id3v1+id3v2"};
408 afhi->chunks_total = 0;
409 afhi->chunk_table = para_malloc(chunk_table_size * sizeof(uint32_t));
412 struct timeval tmp, cct; /* current chunk time */
414 len = find_valid_start(map, numbytes, &fpos, &header);
418 if (!afhi->chunks_total)
420 end = afhi->chunk_table[afhi->chunks_total - 1] + fl;
421 afhi->chunk_table[afhi->chunks_total]
422 = PARA_MIN(end, numbytes);
425 ret = header_frequency(&header);
429 ret = header_bitrate(&header);
433 ret = frame_length(&header);
437 tmp.tv_sec = fl - header.padding;
439 tv_divide(br * 125, &tmp, &cct);
440 tv_add(&cct, &total_time, &tmp);
442 if (afhi->chunks_total >= chunk_table_size) {
443 chunk_table_size *= 2;
444 afhi->chunk_table = para_realloc(afhi->chunk_table,
445 chunk_table_size * sizeof(uint32_t));
447 afhi->chunk_table[afhi->chunks_total] = fpos;
448 afhi->chunks_total++;
451 if (afhi->chunks_total != 1 && old_br != br)
456 if (!freq_sum || !br_sum)
458 afhi->bitrate = br_sum / afhi->chunks_total;
459 afhi->frequency = freq_sum / afhi->chunks_total;
460 afhi->channels = header_channels(&header);
461 afhi->seconds_total = (tv2ms(&total_time) + 500) / 1000;
462 tv_divide(afhi->chunks_total, &total_time, &afhi->chunk_tv);
463 PARA_DEBUG_LOG("%lu chunks, each %lums\n", afhi->chunks_total,
464 tv2ms(&afhi->chunk_tv));
465 ret = mp3_get_id3(map, numbytes, fd, &afhi->tags);
466 afhi->techinfo = make_message("%cbr, %s, %s tags", vbr? 'v' : 'c',
467 header_mode(&header), tag_versions[ret]);
470 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
471 free(afhi->chunk_table);
476 * Read mp3 information from audio file
478 static int mp3_get_file_info(char *map, size_t numbytes, int fd,
479 struct afh_info *afhi)
483 ret = mp3_read_info((unsigned char *)map, numbytes, fd, afhi);
486 if (afhi->seconds_total < 2 || !afhi->chunks_total)
491 static const char* mp3_suffixes[] = {"mp3", NULL};
494 * the init function of the mp3 audio format handler
496 * \param afh pointer to the struct to initialize
498 void mp3_init(struct audio_format_handler *afh)
500 afh->get_file_info = mp3_get_file_info;
501 afh->suffixes = mp3_suffixes;