1 #ifndef DISABLE_MPEG_AUDIO
2
3 /* GPL clean */
4
5 #include <ctype.h>
6 #include <stdlib.h>
7 #include <signal.h>
8 #include <errno.h>
9
10 #include <sys/types.h>
11 #include <sys/stat.h>
12 #ifdef _WIN32
13 #include <time.h>
14 #else
15 #include <sys/time.h>
16 #endif
17
18 #include <fcntl.h>
19
20 #include "mpg123.h"
21 #include "common.h"
22
23 int tabsel_123[2][3][16] = {
24 { {0,32,64,96,128,160,192,224,256,288,320,352,384,416,448,},
25 {0,32,48,56, 64, 80, 96,112,128,160,192,224,256,320,384,},
26 {0,32,40,48, 56, 64, 80, 96,112,128,160,192,224,256,320,} },
27
28 { {0,32,48,56,64,80,96,112,128,144,160,176,192,224,256,},
29 {0,8,16,24,32,40,48,56,64,80,96,112,128,144,160,},
30 {0,8,16,24,32,40,48,56,64,80,96,112,128,144,160,} }
31 };
32
33 long freqs[10] = { 44100, 48000, 32000, 22050, 24000, 16000, 11025, 12000, 8000, 0 };
34
35 static int decode_header(struct frame *fr,unsigned long newhead);
36
read_frame_init(struct frame * fr)37 void read_frame_init (struct frame *fr)
38 {
39 fr->firsthead = 0;
40 fr->thishead = 0;
41 fr->freeformatsize = 0;
42 }
43
head_check(unsigned long head)44 static int head_check(unsigned long head)
45 {
46 if((head & 0xffe00000) != 0xffe00000)
47 return FALSE;
48 if(!((head>>17)&3))
49 return FALSE;
50 if( ((head>>12)&0xf) == 0xf)
51 return FALSE;
52 if( ((head>>10)&0x3) == 0x3 )
53 return FALSE;
54
55 return TRUE;
56 }
57
almpa_head_backcheck(unsigned long head)58 int almpa_head_backcheck(unsigned long head)
59 {
60 head = (((head&0xFF)<<24) | ((head&0xFF00)<<8) | ((head&0xFF0000)>>8) |
61 (head>>24));
62
63 if((head & 0xffe00000) != 0xffe00000)
64 return FALSE;
65 if(!((head>>17)&3))
66 return FALSE;
67 if( ((head>>12)&0xf) == 0xf)
68 return FALSE;
69 if( ((head>>10)&0x3) == 0x3 )
70 return FALSE;
71
72 return TRUE;
73 }
74
75
76 /*****************************************************************
77 * read next frame
78 */
read_frame(APEG_LAYER * layer,struct frame * fr)79 int read_frame(APEG_LAYER *layer, struct frame *fr)
80 {
81 struct mpstr *mp = &(layer->audio.mp);
82 unsigned long newhead, oldhead;
83 int ret;
84
85 oldhead = fr->thishead;
86
87 almpa_head_read(layer, &newhead);
88 while(!decode_header(fr,newhead))
89 {
90 if(newhead == ISO_END_CODE)
91 return ALMPA_EOF;
92
93 almpa_head_shift(layer, &newhead);
94 }
95
96 layer->audio.inited = FALSE;
97 if(oldhead)
98 {
99 if((oldhead & 0xc00) == (fr->thishead & 0xc00))
100 {
101 if( (oldhead & 0xc0) == 0 && (fr->thishead & 0xc0) == 0)
102 layer->audio.inited = TRUE;
103 else if( (oldhead & 0xc0) > 0 && (fr->thishead & 0xc0) > 0)
104 layer->audio.inited = TRUE;
105 }
106 }
107
108 if(!fr->bitrate_index)
109 fr->framesize = fr->freeformatsize + fr->padsize;
110
111 // fprintf(stderr,"Reading %d\n",fr->framesize);
112
113 /* flip/init buffer for Layer 3 */
114 /* FIXME for reentrance */
115 mp->bsbufold = mp->bsbuf;
116 mp->bsbufold_end = mp->bsbufend[mp->bsnum];
117 mp->bsbuf = mp->bsspace[mp->bsnum]+512;
118 mp->bsnum ^= 1;//(bsnum + 1) & 1;
119 mp->bsbufend[mp->bsnum] = fr->framesize;
120
121 /* read main data into memory */
122 ret = almpa_read_bytes(layer, mp->bsbuf, fr->framesize);
123 if(ret < fr->framesize)
124 memset(mp->bsbuf+ret, 0, fr->framesize-ret);
125
126 /* Test */
127 if(!fr->vbr) {
128 fr->vbr = getVBRHeader(&(fr->vbr_header), mp->bsbuf, fr);
129 }
130
131 mp->bsi.bitindex = 0;
132 mp->bsi.wordpointer = (unsigned char*)mp->bsbuf;
133
134 /* skip crc, we are byte aligned here */
135 if(fr->error_protection)
136 mp->bsi.wordpointer += 2;
137
138 return ALMPA_OK;
139 }
140
141 /*
142 * decode a header and write the information
143 * into the frame structure
144 */
decode_header(struct frame * fr,unsigned long newhead)145 static int decode_header(struct frame *fr,unsigned long newhead)
146 {
147 if(!head_check(newhead)) {
148 // fprintf(stderr,"Oops header is wrong %08lx\n",newhead);
149 return 0;
150 }
151
152 if( newhead & (1<<20) ) {
153 fr->lsf = (newhead & (1<<19)) ? 0x0 : 0x1;
154 fr->mpeg25 = 0;
155 }
156 else {
157 fr->lsf = 1;
158 fr->mpeg25 = 1;
159 }
160
161 /*
162 * CHECKME: should be add more consistency checks here ?
163 * changed layer, changed CRC bit, changed sampling frequency
164 */
165 {
166 fr->lay = 4-((newhead>>17)&3);
167 if( ((newhead>>10)&0x3) == 0x3) {
168 fprintf(stderr,"Stream error\n");
169 return 0;
170 }
171 if(fr->mpeg25) {
172 fr->sampling_frequency = 6 + ((newhead>>10)&0x3);
173 }
174 else
175 fr->sampling_frequency = ((newhead>>10)&0x3) + (fr->lsf*3);
176 fr->error_protection = ((newhead>>16)&0x1)^0x1;
177 }
178
179 fr->bitrate_index = ((newhead>>12)&0xf);
180 fr->padding = ((newhead>>9)&0x1);
181 fr->extension = ((newhead>>8)&0x1);
182 fr->mode = ((newhead>>6)&0x3);
183 fr->mode_ext = ((newhead>>4)&0x3);
184 fr->copyright = ((newhead>>3)&0x1);
185 fr->original = ((newhead>>2)&0x1);
186 fr->emphasis = newhead & 0x3;
187
188 fr->stereo = (fr->mode == MPG_MD_MONO) ? 1 : 2;
189
190 switch(fr->lay) {
191 case 1:
192 fr->framesize = (long) tabsel_123[fr->lsf][0][fr->bitrate_index] * 12000;
193 fr->framesize /= freqs[fr->sampling_frequency];
194 fr->framesize = ((fr->framesize+fr->padding)<<2)-4;
195 fr->sideInfoSize = 0;
196 fr->padsize = fr->padding << 2;
197 break;
198 case 2:
199 fr->framesize = (long) tabsel_123[fr->lsf][1][fr->bitrate_index] * 144000;
200 fr->framesize /= freqs[fr->sampling_frequency];
201 fr->framesize += fr->padding - 4;
202 fr->sideInfoSize = 0;
203 fr->padsize = fr->padding;
204 break;
205 case 3:
206 if(fr->lsf)
207 fr->sideInfoSize = (fr->stereo == 1) ? 9 : 17;
208 else
209 fr->sideInfoSize = (fr->stereo == 1) ? 17 : 32;
210 if(fr->error_protection)
211 fr->sideInfoSize += 2;
212 fr->framesize = (long) tabsel_123[fr->lsf][2][fr->bitrate_index] * 144000;
213 fr->framesize /= freqs[fr->sampling_frequency]<<(fr->lsf);
214 fr->framesize = fr->framesize + fr->padding - 4;
215 fr->padsize = fr->padding;
216 break;
217 default:
218 fprintf(stderr,"Sorry, unknown layer type.\n");
219 return (0);
220 }
221
222 if(!fr->bitrate_index) {
223 /* fprintf(stderr,"Warning, Free format not heavily tested: (head %08lx)\n",newhead); */
224 fr->framesize = 0;
225 }
226 fr->thishead = newhead;
227
228 return 1;
229 }
230
231 #if 0
232 void print_rheader(struct frame *fr)
233 {
234 static char *modes[4] = { "Stereo", "Joint-Stereo", "Dual-Channel", "Single-Channel" };
235 static char *layers[4] = { "Unknown" , "I", "II", "III" };
236 static char *mpeg_type[2] = { "1.0" , "2.0" };
237
238 /* version, layer, freq, mode, channels, bitrate, BPF */
239 fprintf(stderr,"@I %s %s %ld %s %d %d %d\n",
240 mpeg_type[fr->lsf],layers[fr->lay],freqs[fr->sampling_frequency],
241 modes[fr->mode],fr->stereo,
242 tabsel_123[fr->lsf][fr->lay-1][fr->bitrate_index],
243 fr->framesize+4);
244 }
245
246 void print_header(struct frame *fr)
247 {
248 static char *modes[4] = { "Stereo", "Joint-Stereo", "Dual-Channel", "Single-Channel" };
249 static char *layers[4] = { "Unknown" , "I", "II", "III" };
250
251 fprintf(stderr,"MPEG %s, Layer: %s, Freq: %ld, mode: %s, modext: %d, BPF : %d\n",
252 fr->mpeg25 ? "2.5" : (fr->lsf ? "2.0" : "1.0"),
253 layers[fr->lay],freqs[fr->sampling_frequency],
254 modes[fr->mode],fr->mode_ext,fr->framesize+4);
255 fprintf(stderr,"Channels: %d, copyright: %s, original: %s, CRC: %s, emphasis: %d.\n",
256 fr->stereo,fr->copyright?"Yes":"No",
257 fr->original?"Yes":"No",fr->error_protection?"Yes":"No",
258 fr->emphasis);
259 fprintf(stderr,"%sBitrate: %d Kbits/s, Extension value: %d\n",
260 fr->vbr ? "Average " : "",
261 fr->vbr ?
262 (int) (fr->vbr_header.bytes * 8 / (compute_tpf(fr) * fr->vbr_header.frames * 1000)):
263 (tabsel_123[fr->lsf][fr->lay-1][fr->bitrate_index]),
264 fr->extension);
265 }
266
267 void print_header_compact(struct frame *fr)
268 {
269 static char *modes[4] = { "stereo", "joint-stereo", "dual-channel", "mono" };
270 static char *layers[4] = { "Unknown" , "I", "II", "III" };
271
272 fprintf(stderr,"MPEG %s layer %s, %d kbit/s, %ld Hz %s\n",
273 fr->mpeg25 ? "2.5" : (fr->lsf ? "2.0" : "1.0"),
274 layers[fr->lay],
275 tabsel_123[fr->lsf][fr->lay-1][fr->bitrate_index],
276 freqs[fr->sampling_frequency], modes[fr->mode]);
277 }
278
279 void print_id3_tag(unsigned char *buf)
280 {
281 struct id3tag {
282 char tag[3];
283 char title[30];
284 char artist[30];
285 char album[30];
286 char year[4];
287 char comment[30];
288 unsigned char genre;
289 };
290 struct id3tag *tag = (struct id3tag *) buf;
291 char title[31]={0,};
292 char artist[31]={0,};
293 char album[31]={0,};
294 char year[5]={0,};
295 char comment[31]={0,};
296 char genre[31]={0,};
297
298 if(1)
299 return;
300
301 strncpy(title,tag->title,30);
302 strncpy(artist,tag->artist,30);
303 strncpy(album,tag->album,30);
304 strncpy(year,tag->year,4);
305 strncpy(comment,tag->comment,30);
306
307 if ( tag->genre < sizeof(genre_table)/sizeof(*genre_table) ) {
308 strncpy(genre, genre_table[tag->genre], 30);
309 } else {
310 strncpy(genre,"Unknown",30);
311 }
312
313 fprintf(stderr,"Title : %-30s Artist: %s\n",title,artist);
314 fprintf(stderr,"Album : %-30s Year : %4s\n",album,year);
315 fprintf(stderr,"Comment: %-30s Genre : %s\n",comment,genre);
316 }
317 #endif
318
set_pointer(struct mpstr * mp,int ssize,long backstep)319 void set_pointer(struct mpstr *mp, int ssize, long backstep)
320 {
321 mp->bsi.wordpointer = mp->bsbuf + ssize - backstep;
322 if(backstep)
323 memcpy(mp->bsi.wordpointer, mp->bsbufold+mp->bsbufold_end-backstep, backstep);
324 mp->bsi.bitindex = 0;
325 }
326
327 /********************************/
328
compute_bpf(struct frame * fr)329 double compute_bpf(struct frame *fr)
330 {
331 double bpf;
332
333 if(!fr->bitrate_index) {
334 return fr->freeformatsize + 4;
335 }
336
337 switch(fr->lay) {
338 case 1:
339 bpf = tabsel_123[fr->lsf][0][fr->bitrate_index];
340 bpf *= 12000.0 * 4.0;
341 bpf /= freqs[fr->sampling_frequency] <<(fr->lsf);
342 break;
343 case 2:
344 case 3:
345 bpf = tabsel_123[fr->lsf][fr->lay-1][fr->bitrate_index];
346 bpf *= 144000;
347 bpf /= freqs[fr->sampling_frequency] << (fr->lsf);
348 break;
349 default:
350 bpf = 1.0;
351 }
352
353 return bpf;
354 }
355
compute_tpf(struct frame * fr)356 double compute_tpf(struct frame *fr)
357 {
358 static int bs[4] = { 0,384,1152,1152 };
359 double tpf;
360
361 tpf = (double) bs[fr->lay];
362 tpf /= freqs[fr->sampling_frequency] << (fr->lsf);
363 return tpf;
364 }
365
366 /*int get_songlen(st ruct reader *rds, struct frame *fr, int no)
367 {
368 double tpf;
369
370 if(!fr)
371 return 0;
372
373 if(no < 0)
374 {
375 if(!rds || rds->filelen < 0)
376 return 0;
377 no = (double) rds->filelen / compute_bpf(fr);
378 }
379
380 tpf = compute_tpf(fr);
381 return no*tpf;
382 }*/
383 #endif
384