aboutsummaryrefslogtreecommitdiffstats
path: root/codecs/mp3/src/isbt.c
blob: bc240bdb90fcb556a87df9ecd383b92522825f95 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
/*____________________________________________________________________________
	
	FreeAmp - The Free MP3 Player

        MP3 Decoder originally Copyright (C) 1995-1997 Xing Technology
        Corp.  http://www.xingtech.com

	Portions Copyright (C) 1998-1999 EMusic.com

	This program is free software; you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation; either version 2 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to the Free Software
	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	
	$Id$
____________________________________________________________________________*/

/****  isbt.c  ***************************************************

MPEG audio decoder, dct and window
portable C       integer version of csbt.c

mods 11/15/95 for Layer I

mods 1/7/97 warnings

******************************************************************/

#include <stdlib.h>
#include <stdio.h>
#include <float.h>
#include <math.h>
#include "itype.h"


#ifdef _MSC_VER
#pragma warning(disable: 4244)
#pragma warning(disable: 4056)
#endif



/* asm is quick only, c code does not need separate window for right */
/* full is opposite of quick */
#ifdef  FULL_INTEGER
#define i_window_dual_right   i_window_dual
#define i_window16_dual_right i_window16_dual
#define i_window8_dual_right  i_window8_dual
#endif


void i_dct32(SAMPLEINT * sample, WININT * vbuf);
void i_dct32_dual(SAMPLEINT * sample, WININT * vbuf);
void i_dct32_dual_mono(SAMPLEINT * sample, WININT * vbuf);

void i_dct16(SAMPLEINT * sample, WININT * vbuf);
void i_dct16_dual(SAMPLEINT * sample, WININT * vbuf);
void i_dct16_dual_mono(SAMPLEINT * sample, WININT * vbuf);

void i_dct8(SAMPLEINT * sample, WININT * vbuf);
void i_dct8_dual(SAMPLEINT * sample, WININT * vbuf);
void i_dct8_dual_mono(SAMPLEINT * sample, WININT * vbuf);


void i_window(WININT * vbuf, int vb_ptr, short *pcm);
void i_window_dual(WININT * vbuf, int vb_ptr, short *pcm);
void i_window_dual_right(WININT * vbuf, int vb_ptr, short *pcm);

void i_window16(WININT * vbuf, int vb_ptr, short *pcm);
void i_window16_dual(WININT * vbuf, int vb_ptr, short *pcm);
void i_window16_dual_right(WININT * vbuf, int vb_ptr, short *pcm);

void i_window8(WININT * vbuf, int vb_ptr, short *pcm);
void i_window8_dual(WININT * vbuf, int vb_ptr, short *pcm);
void i_window8_dual_right(WININT * vbuf, int vb_ptr, short *pcm);

/*--------------------------------------------------------------------*/
/*--  floating point window coefs  ---*/
/*--  for integer-quick window, table used to generate integer coefs --*/
static float wincoef[264] =
{
#include "tableawd.h"
};

/* circular window buffers */
/* extern windows because of asm */
static signed int vb_ptr;

// static WININT vbuf[512];
//static WININT vbuf2[512];
extern WININT vbuf[512];
extern WININT vbuf2[512];

DCTCOEF *i_dct_coef_addr();

/*======================================================================*/
static void gencoef()		/* gen coef for N=32 */
{
   int p, n, i, k;
   double t, pi;
   DCTCOEF *coef32;

   coef32 = i_dct_coef_addr();


   pi = 4.0 * atan(1.0);
   n = 16;
   k = 0;
   for (i = 0; i < 5; i++, n = n / 2)
   {
      for (p = 0; p < n; p++, k++)
      {
	 t = (pi / (4 * n)) * (2 * p + 1);
	 coef32[k] = (1 << DCTBITS) * (0.50 / cos(t)) + 0.5;
      }
   }
}
/*------------------------------------------------------------*/
WINCOEF *i_wincoef_addr();
static void genwincoef_q()	/* gen int window coefs from floating table */
{
   int i, j, k, m;
   float x;
   WINCOEF *iwincoef;

   iwincoef = i_wincoef_addr();


/*--- coefs generated inline for quick window ---*/
/*-- quick uses only 116 coefs --*/

   k = 0;
   m = 0;
   for (i = 0; i < 16; i++)
   {
      k += 5;
      for (j = 0; j < 7; j++)
      {
	 x = (1 << WINBITS) * wincoef[k++];
	 if (x > 0.0)
	    x += 0.5;
	 else
	    x -= 0.5;
	 iwincoef[m++] = x;
      }
      k += 4;
   }
   k++;
   for (j = 0; j < 4; j++)
   {
      x = (1 << WINBITS) * wincoef[k++];
      if (x > 0.0)
	 x += 0.5;
      else
	 x -= 0.5;
      iwincoef[m++] = x;
   }
}
/*------------------------------------------------------------*/
static void genwincoef()	/* gen int window coefs from floating table */
{
   int i;
   float x;
   WINCOEF *iwincoef;
   WINCOEF *i_wincoef_addr();

   iwincoef = i_wincoef_addr();

   for (i = 0; i < 264; i++)
   {
      x = (1 << WINBITS) * wincoef[i];
      if (x > 0.0)
	 x += 0.5;
      else
	 x -= 0.5;
      iwincoef[i] = x;
   }
}
/*------------------------------------------------------------*/
void i_sbt_init()
{
   int i;
   static int first_pass = 1;

#ifdef FULL_INTEGER
   static int full_integer = 1;

#else
   static int full_integer = 0;

#endif

   if (first_pass)
   {
      gencoef();
      if (full_integer)
	 genwincoef();
      else
	 genwincoef_q();
      first_pass = 0;
   }

/* clear window vbuf */
   for (i = 0; i < 512; i++)
      vbuf[i] = vbuf2[i] = 0;
   vb_ptr = 0;

}
/*==============================================================*/
/*==============================================================*/
/*==============================================================*/
void i_sbt_mono(SAMPLEINT * sample, short *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      i_dct32(sample, vbuf + vb_ptr);
      i_window(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 32) & 511;
      pcm += 32;
   }

}
/*------------------------------------------------------------*/
void i_sbt_dual(SAMPLEINT * sample, short *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      i_dct32_dual(sample, vbuf + vb_ptr);
      i_dct32_dual(sample + 1, vbuf2 + vb_ptr);
      i_window_dual(vbuf, vb_ptr, pcm);
      i_window_dual_right(vbuf2, vb_ptr, pcm + 1);
      sample += 64;
      vb_ptr = (vb_ptr - 32) & 511;
      pcm += 64;
   }
}
/*------------------------------------------------------------*/
/* convert dual to mono */
void i_sbt_dual_mono(SAMPLEINT * sample, short *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      i_dct32_dual_mono(sample, vbuf + vb_ptr);
      i_window(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 32) & 511;
      pcm += 32;
   }
}
/*------------------------------------------------------------*/
/* convert dual to left */
void i_sbt_dual_left(SAMPLEINT * sample, short *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      i_dct32_dual(sample, vbuf + vb_ptr);
      i_window(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 32) & 511;
      pcm += 32;
   }
}
/*------------------------------------------------------------*/
/* convert dual to right */
void i_sbt_dual_right(SAMPLEINT * sample, short *pcm, int n)
{
   int i;

   sample++;			/* point to right chan */
   for (i = 0; i < n; i++)
   {
      i_dct32_dual(sample, vbuf + vb_ptr);
      i_window(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 32) & 511;
      pcm += 32;
   }
}
/*------------------------------------------------------------*/
/*---------------- 16 pt sbt's  -------------------------------*/
/*------------------------------------------------------------*/
void i_sbt16_mono(SAMPLEINT * sample, short *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      i_dct16(sample, vbuf + vb_ptr);
      i_window16(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 16) & 255;
      pcm += 16;
   }

}
/*------------------------------------------------------------*/
void i_sbt16_dual(SAMPLEINT * sample, short *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      i_dct16_dual(sample, vbuf + vb_ptr);
      i_dct16_dual(sample + 1, vbuf2 + vb_ptr);
      i_window16_dual(vbuf, vb_ptr, pcm);
      i_window16_dual_right(vbuf2, vb_ptr, pcm + 1);
      sample += 64;
      vb_ptr = (vb_ptr - 16) & 255;
      pcm += 32;
   }

}
/*------------------------------------------------------------*/
void i_sbt16_dual_mono(SAMPLEINT * sample, short *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      i_dct16_dual_mono(sample, vbuf + vb_ptr);
      i_window16(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 16) & 255;
      pcm += 16;
   }
}
/*------------------------------------------------------------*/
void i_sbt16_dual_left(SAMPLEINT * sample, short *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      i_dct16_dual(sample, vbuf + vb_ptr);
      i_window16(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 16) & 255;
      pcm += 16;
   }
}
/*------------------------------------------------------------*/
void i_sbt16_dual_right(SAMPLEINT * sample, short *pcm, int n)
{
   int i;

   sample++;
   for (i = 0; i < n; i++)
   {
      i_dct16_dual(sample, vbuf + vb_ptr);
      i_window16(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 16) & 255;
      pcm += 16;
   }
}
/*------------------------------------------------------------*/
/*---------------- 8 pt sbt's  -------------------------------*/
/*------------------------------------------------------------*/
void i_sbt8_mono(SAMPLEINT * sample, short *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      i_dct8(sample, vbuf + vb_ptr);
      i_window8(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 8) & 127;
      pcm += 8;
   }

}
/*------------------------------------------------------------*/
void i_sbt8_dual(SAMPLEINT * sample, short *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      i_dct8_dual(sample, vbuf + vb_ptr);
      i_dct8_dual(sample + 1, vbuf2 + vb_ptr);
      i_window8_dual(vbuf, vb_ptr, pcm);
      i_window8_dual_right(vbuf2, vb_ptr, pcm + 1);
      sample += 64;
      vb_ptr = (vb_ptr - 8) & 127;
      pcm += 16;
   }
}
/*------------------------------------------------------------*/
void i_sbt8_dual_mono(SAMPLEINT * sample, short *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      i_dct8_dual_mono(sample, vbuf + vb_ptr);
      i_window8(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 8) & 127;
      pcm += 8;
   }
}
/*------------------------------------------------------------*/
void i_sbt8_dual_left(SAMPLEINT * sample, short *pcm, int n)
{
   int i;

   for (i = 0; i < n; i++)
   {
      i_dct8_dual(sample, vbuf + vb_ptr);
      i_window8(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 8) & 127;
      pcm += 8;
   }
}
/*------------------------------------------------------------*/
void i_sbt8_dual_right(SAMPLEINT * sample, short *pcm, int n)
{
   int i;

   sample++;
   for (i = 0; i < n; i++)
   {
      i_dct8_dual(sample, vbuf + vb_ptr);
      i_window8(vbuf, vb_ptr, pcm);
      sample += 64;
      vb_ptr = (vb_ptr - 8) & 127;
      pcm += 8;
   }
}
/*------------------------------------------------------------*/
/*--- 8 bit output ----------------*/
#include "isbtb.c"
/*----------------------------------*/

#ifdef _MSC_VER
#pragma warning(default: 4244)
#pragma warning(default: 4056)
#endif