2 * Copyright (C) 2003-2007 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 /** \file mp3_afh.c para_server's mp3 audio format handler */
22 * This file is based in part on mp3tech.c and mp3tech.h, Copyright (C)
23 * 2000-2001 Cedric Tefft <cedric@earthling.net>, which in turn is based
26 * * MP3Info 0.5 by Ricardo Cerqueira <rmc@rccn.net>
27 * * MP3Stat 0.9 by Ed Sweetman <safemode@voicenet.com> and
28 * Johannes Overmann <overmann@iname.com>
31 #include "server.cmdline.h"
38 /** \cond some defines and structs which are only used in this file */
41 * MIN_CONSEC_GOOD_FRAMES defines how many consecutive valid MP3 frames we need
42 * to see before we decide we are looking at a real MP3 file
44 #define MIN_CONSEC_GOOD_FRAMES 4
46 #define FRAME_HEADER_SIZE 4
47 #define MIN_FRAME_SIZE 21
58 unsigned int copyright
;
59 unsigned int original
;
60 unsigned int emphasis
;
72 struct mp3header header
;
76 long unsigned br_average
;
77 long unsigned seconds
;
82 static const int frequencies
[3][4] = {
83 {22050,24000,16000,50000}, /* MPEG 2.0 */
84 {44100,48000,32000,50000}, /* MPEG 1.0 */
85 {11025,12000,8000,50000} /* MPEG 2.5 */
88 static const int mp3info_bitrate
[2][3][14] = {
90 {32,48,56,64,80,96,112,128,144,160,176,192,224,256}, /* layer 1 */
91 {8,16,24,32,40,48,56,64,80,96,112,128,144,160}, /* layer 2 */
92 {8,16,24,32,40,48,56,64,80,96,112,128,144,160} /* layer 3 */
96 {32,64,96,128,160,192,224,256,288,320,352,384,416,448}, /* layer 1 */
97 {32,48,56,64,80,96,112,128,160,192,224,256,320,384}, /* layer 2 */
98 {32,40,48,56,64,80,96,112,128,160,192,224,256,320} /* layer 3 */
102 static const int frame_size_index
[] = {24000, 72000, 72000};
103 static const char *mode_text
[] = {"stereo", "joint stereo", "dual channel", "mono", "invalid"};
106 static struct mp3info mp3
;
107 static struct audio_format_handler
*af
;
108 static ssize_t num_chunks
;
110 static int header_frequency(struct mp3header
*h
)
112 if (h
->version
> 2 || h
->freq
> 3)
113 return -E_HEADER_FREQ
;
114 return frequencies
[h
->version
][h
->freq
];
117 static const char *header_mode(struct mp3header
*h
)
120 h
->mode
= 4; /* invalid */
121 return mode_text
[h
->mode
];
123 static int header_bitrate(struct mp3header
*h
)
125 if (h
->layer
> 3 || h
->bitrate
> 14)
126 return -E_HEADER_BITRATE
;
127 return mp3info_bitrate
[h
->version
& 1][3 - h
->layer
][h
->bitrate
- 1];
130 static int frame_length(struct mp3header
*header
)
132 int hb
, hf
= header_frequency(header
);
136 hb
= header_bitrate(header
);
139 if (header
->sync
!= 0xFFE || header
->layer
> 3)
141 return frame_size_index
[3 - header
->layer
] *
142 ((header
->version
& 1) + 1) * hb
/ hf
146 static void write_info_str(struct audio_format_info
*afi
)
148 int v
= mp3
.id3_isvalid
;
150 snprintf(afi
->info_string
, MMD_INFO_SIZE
,
151 "audio_file_info1:%d x %lums, %lu kbit/s (%cbr) %i KHz %s\n"
152 "audio_file_info2:%s, by %s\n"
153 "audio_file_info3:A: %s, Y: %s, C: %s\n",
155 tv2ms(&afi
->chunk_tv
),
159 header_mode(&mp3
.header
),
160 v
&& *mp3
.id3
.title
? mp3
.id3
.title
: "(title tag not set)",
161 v
&& *mp3
.id3
.artist
? mp3
.id3
.artist
: "(artist tag not set)",
162 v
&& *mp3
.id3
.album
? mp3
.id3
.album
: "(album tag not set)",
163 v
&& *mp3
.id3
.year
? mp3
.id3
.year
: "????",
164 v
&& *mp3
.id3
.comment
? mp3
.id3
.comment
: "(comment tag not set)"
169 * Remove trailing whitespace from the end of a string
171 static char *unpad(char *string
)
173 char *pos
= string
+ strlen(string
) - 1;
174 while (isspace(pos
[0]))
179 static int compare_headers(struct mp3header
*h1
,struct mp3header
*h2
)
181 if ((*(uint
*)h1
) == (*(uint
*)h2
))
183 if ((h1
->version
== h2
->version
) &&
184 (h1
->layer
== h2
->layer
) &&
185 (h1
->crc
== h2
->crc
) &&
186 (h1
->freq
== h2
->freq
) &&
187 (h1
->mode
== h2
->mode
) &&
188 (h1
->copyright
== h2
->copyright
) &&
189 (h1
->original
== h2
->original
) &&
190 (h1
->emphasis
== h2
->emphasis
))
196 * get next MP3 frame header.
198 * \param stream to read the header from
199 * \param header structure that gets filled in by get_header()
201 * \return On success, the header frame length is returned. A return value of
202 * zero means that we did not retrieve a valid frame header, and a negative
203 * return value indicates an error.
205 static int get_header(FILE *file
, struct mp3header
*header
)
207 unsigned char buffer
[FRAME_HEADER_SIZE
];
210 if (!file
|| !header
)
211 return -E_MP3_NO_FILE
;
212 ret
= para_fread(buffer
, FRAME_HEADER_SIZE
, 1, file
);
213 if (ret
< FRAME_HEADER_SIZE
) {
215 return ret
< 0? ret
: 0;
217 header
->layer
= (buffer
[1] >> 1) & 3;
218 header
->sync
= (((int)buffer
[0]<<4) | ((int)(buffer
[1]&0xE0)>>4));
219 if (buffer
[1] & 0x10)
220 header
->version
= (buffer
[1] >> 3) & 1;
223 if ((header
->sync
!= 0xFFE) || (header
->layer
!= 1)) {
225 // PARA_DEBUG_LOG("%s: header not found\n", __func__);
228 header
->crc
= buffer
[1] & 1;
229 header
->bitrate
= (buffer
[2] >> 4) & 0x0F;
230 // PARA_DEBUG_LOG("%s: found header, bitrate: %u\n", __func__,
232 header
->freq
= (buffer
[2] >> 2) & 0x3;
233 header
->padding
= (buffer
[2] >>1) & 0x1;
234 header
->mode
= (buffer
[3] >> 6) & 0x3;
235 fl
= frame_length(header
);
236 return (fl
>= MIN_FRAME_SIZE
)? fl
: -E_FRAME_LENGTH
;
240 * find the next mp3 header
242 * \return On success, the length of the next frame header. If the end of the
243 * file was reached, the function returns zero. On errors, a negative value is
247 static int mp3_seek_next_header(void)
249 int k
, l
= 0, c
, first_len
, ret
;
250 struct mp3header h
, h2
;
251 long valid_start
= 0;
254 while ((c
= fgetc(infile
)) != 255 && (c
!= EOF
))
259 valid_start
= ftell(infile
);
260 first_len
= get_header(infile
, &h
);
263 ret
= para_fseek(infile
, first_len
- FRAME_HEADER_SIZE
, SEEK_CUR
);
266 for (k
= 1; k
< MIN_CONSEC_GOOD_FRAMES
; k
++) {
267 if ((l
= get_header(infile
, &h2
)) <= 0)
269 if (!compare_headers(&h
, &h2
))
271 ret
= para_fseek(infile
, l
- FRAME_HEADER_SIZE
, SEEK_CUR
);
275 if (k
== MIN_CONSEC_GOOD_FRAMES
) {
276 ret
= para_fseek(infile
, valid_start
, SEEK_SET
);
279 memcpy(&(mp3
.header
), &h2
, sizeof(struct mp3header
));
285 static int mp3_get_id3(void)
291 mp3
.id3
.title
[0] = '\0';
292 mp3
.id3
.artist
[0] = '\0';
293 mp3
.id3
.album
[0] = '\0';
294 mp3
.id3
.comment
[0] = '\0';
295 mp3
.id3
.year
[0] = '\0';
296 ret
= para_fseek(infile
, -128, SEEK_END
);
299 if (para_fread(fbuf
, 1, 3, infile
) < 0)
302 if (strcmp("TAG", fbuf
)) {
303 PARA_INFO_LOG("%s", "no id3 tag\n");
306 ret
= para_fseek(infile
, -125, SEEK_END
);
309 if (para_fread(mp3
.id3
.title
, 1, 30, infile
) != 30)
311 mp3
.id3
.title
[30] = '\0';
312 if (para_fread(mp3
.id3
.artist
, 1, 30, infile
) != 30)
314 mp3
.id3
.artist
[30] = '\0';
315 if (para_fread(mp3
.id3
.album
, 1, 30, infile
) != 30)
317 mp3
.id3
.album
[30] = '\0';
318 if (para_fread(mp3
.id3
.year
, 1, 4, infile
) != 4)
320 mp3
.id3
.year
[4] = '\0';
321 if (para_fread(mp3
.id3
.comment
, 1, 30, infile
) != 30)
323 mp3
.id3
.comment
[30] = '\0';
325 unpad(mp3
.id3
.title
);
326 unpad(mp3
.id3
.artist
);
327 unpad(mp3
.id3
.album
);
329 unpad(mp3
.id3
.comment
);
333 static int find_valid_start(void)
338 return -E_MP3_NO_FILE
;
339 frame_len
= get_header(infile
, &mp3
.header
);
343 frame_len
= mp3_seek_next_header();
347 ret
= para_fseek(infile
, -FRAME_HEADER_SIZE
, SEEK_CUR
);
352 return -E_FRAME_LENGTH
;
356 static int mp3_read_info(struct audio_format_info
*afi
)
358 long fl_avg
= 0, freq_avg
= 0, br_avg
= 0;
359 int ret
, len
= 0, old_br
= -1;
360 struct timeval total_time
= {0, 0};
361 unsigned chunk_table_size
= 1000; /* gets increased on demand */
364 afi
->chunk_table
= para_malloc(chunk_table_size
* sizeof(size_t));
373 struct timeval tmp
, cct
; /* current chunk time */
375 ret
= para_fseek(infile
, len
, SEEK_CUR
);
379 len
= find_valid_start();
382 freq
= header_frequency(&mp3
.header
);
383 br
= header_bitrate(&mp3
.header
);
384 fl
= frame_length(&mp3
.header
);
385 if (freq
< 0 || br
< 0 || fl
< 0)
389 tv_divide(br
* 125, &tmp
, &cct
);
390 tv_add(&cct
, &total_time
, &tmp
);
392 //PARA_DEBUG_LOG("%s: br: %d, freq: %d, fl: %d, cct: %lu\n", __func__, br, freq, fl, cct.tv_usec);
393 if (num_chunks
>= chunk_table_size
) {
394 chunk_table_size
*= 2;
395 afi
->chunk_table
= para_realloc(afi
->chunk_table
,
396 chunk_table_size
* sizeof(size_t));
398 afi
->chunk_table
[num_chunks
] = ftell(infile
);
399 if (num_chunks
< 10 || !(num_chunks
% 1000))
400 PARA_INFO_LOG("chunk #%d: %zd\n", num_chunks
,
401 afi
->chunk_table
[num_chunks
]);
403 if (num_chunks
== 1) {
404 // entry = ftell(infile);
405 // PARA_INFO_LOG("entry: %zd\n", entry);
412 freq_avg
+= (freq
- freq_avg
) / (num_chunks
+ 1);
413 fl_avg
+= (fl
- fl_avg
) / (num_chunks
+ 1);
414 br_avg
+= (br
- br_avg
) / (num_chunks
+ 1);
420 if (!num_chunks
|| !freq_avg
|| !br_avg
)
422 ret
= para_fseek(infile
, 0, SEEK_END
);
425 afi
->chunk_table
[num_chunks
] = ftell(infile
);
426 mp3
.br_average
= br_avg
;
428 mp3
.seconds
= (tv2ms(&total_time
) + 500) / 1000;
429 tv_divide(num_chunks
, &total_time
, &afi
->chunk_tv
);
431 PARA_DEBUG_LOG("%zu chunks, each %lums\n", num_chunks
, tv2ms(&afi
->chunk_tv
));
432 tv_scale(3, &afi
->chunk_tv
, &afi
->eof_tv
);
433 PARA_DEBUG_LOG("eof timeout: %lu\n", tv2ms(&afi
->eof_tv
));
436 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret
));
437 free(afi
->chunk_table
);
442 * Read mp3 information from audio file
444 static int mp3_get_file_info(FILE *audio_file
, struct audio_format_info
*afi
)
449 return -E_MP3_NO_FILE
;
451 ret
= mp3_read_info(afi
);
457 afi
->chunks_total
= num_chunks
;
458 afi
->seconds_total
= mp3
.seconds
;
459 if (afi
->seconds_total
< 2 || !afi
->chunks_total
)
464 static void mp3_close_audio_file(void)
472 static const char* mp3_suffixes
[] = {"mp3", NULL
};
475 * the init function of the mp3 audio format handler
477 * \param p pointer to the struct to initialize
479 void mp3_init(struct audio_format_handler
*p
)
482 af
->get_file_info
= mp3_get_file_info
;
483 af
->close_audio_file
= mp3_close_audio_file
;
484 af
->suffixes
= mp3_suffixes
;