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12#include <linux/delay.h>
13#include <linux/mISDNif.h>
14#include <linux/mISDNdsp.h>
15#include "core.h"
16#include "dsp.h"
17
18
19s32 dsp_audio_ulaw_to_s32[256];
20
21s32 dsp_audio_alaw_to_s32[256];
22
23s32 *dsp_audio_law_to_s32;
24EXPORT_SYMBOL(dsp_audio_law_to_s32);
25
26
27u8 dsp_audio_s16_to_law[65536];
28EXPORT_SYMBOL(dsp_audio_s16_to_law);
29
30
31u8 dsp_audio_alaw_to_ulaw[256];
32
33static u8 dsp_audio_ulaw_to_alaw[256];
34u8 dsp_silence;
35
36
37
38
39
40
41#define AMI_MASK 0x55
42
43static inline unsigned char linear2alaw(short int linear)
44{
45 int mask;
46 int seg;
47 int pcm_val;
48 static int seg_end[8] = {
49 0xFF, 0x1FF, 0x3FF, 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF
50 };
51
52 pcm_val = linear;
53 if (pcm_val >= 0) {
54
55 mask = AMI_MASK | 0x80;
56 } else {
57
58 mask = AMI_MASK;
59 pcm_val = -pcm_val;
60 }
61
62
63 for (seg = 0; seg < 8; seg++) {
64 if (pcm_val <= seg_end[seg])
65 break;
66 }
67
68 return ((seg << 4) |
69 ((pcm_val >> ((seg) ? (seg + 3) : 4)) & 0x0F)) ^ mask;
70}
71
72
73static inline short int alaw2linear(unsigned char alaw)
74{
75 int i;
76 int seg;
77
78 alaw ^= AMI_MASK;
79 i = ((alaw & 0x0F) << 4) + 8 ;
80 seg = (((int) alaw & 0x70) >> 4);
81 if (seg)
82 i = (i + 0x100) << (seg - 1);
83 return (short int) ((alaw & 0x80) ? i : -i);
84}
85
86static inline short int ulaw2linear(unsigned char ulaw)
87{
88 short mu, e, f, y;
89 static short etab[] = {0, 132, 396, 924, 1980, 4092, 8316, 16764};
90
91 mu = 255 - ulaw;
92 e = (mu & 0x70) / 16;
93 f = mu & 0x0f;
94 y = f * (1 << (e + 3));
95 y += etab[e];
96 if (mu & 0x80)
97 y = -y;
98 return y;
99}
100
101#define BIAS 0x84
102
103static unsigned char linear2ulaw(short sample)
104{
105 static int exp_lut[256] = {
106 0, 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3,
107 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
108 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
109 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
110 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
111 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
112 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
113 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
114 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
115 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
116 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
117 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
118 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
119 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
120 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
121 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7};
122 int sign, exponent, mantissa;
123 unsigned char ulawbyte;
124
125
126 sign = (sample >> 8) & 0x80;
127 if (sign != 0)
128 sample = -sample;
129
130
131 sample = sample + BIAS;
132 exponent = exp_lut[(sample >> 7) & 0xFF];
133 mantissa = (sample >> (exponent + 3)) & 0x0F;
134 ulawbyte = ~(sign | (exponent << 4) | mantissa);
135
136 return ulawbyte;
137}
138
139static int reverse_bits(int i)
140{
141 int z, j;
142 z = 0;
143
144 for (j = 0; j < 8; j++) {
145 if ((i & (1 << j)) != 0)
146 z |= 1 << (7 - j);
147 }
148 return z;
149}
150
151
152void dsp_audio_generate_law_tables(void)
153{
154 int i;
155 for (i = 0; i < 256; i++)
156 dsp_audio_alaw_to_s32[i] = alaw2linear(reverse_bits(i));
157
158 for (i = 0; i < 256; i++)
159 dsp_audio_ulaw_to_s32[i] = ulaw2linear(reverse_bits(i));
160
161 for (i = 0; i < 256; i++) {
162 dsp_audio_alaw_to_ulaw[i] =
163 linear2ulaw(dsp_audio_alaw_to_s32[i]);
164 dsp_audio_ulaw_to_alaw[i] =
165 linear2alaw(dsp_audio_ulaw_to_s32[i]);
166 }
167}
168
169void
170dsp_audio_generate_s2law_table(void)
171{
172 int i;
173
174 if (dsp_options & DSP_OPT_ULAW) {
175
176 for (i = -32768; i < 32768; i++) {
177 dsp_audio_s16_to_law[i & 0xffff] =
178 reverse_bits(linear2ulaw(i));
179 }
180 } else {
181
182 for (i = -32768; i < 32768; i++) {
183 dsp_audio_s16_to_law[i & 0xffff] =
184 reverse_bits(linear2alaw(i));
185 }
186 }
187}
188
189
190
191
192
193
194u8 dsp_audio_seven2law[128];
195u8 dsp_audio_law2seven[256];
196
197
198
199
200
201void
202dsp_audio_generate_seven(void)
203{
204 int i, j, k;
205 u8 spl;
206 u8 sorted_alaw[256];
207
208
209 for (i = 0; i < 256; i++) {
210 j = 0;
211 for (k = 0; k < 256; k++) {
212 if (dsp_audio_alaw_to_s32[k]
213 < dsp_audio_alaw_to_s32[i])
214 j++;
215 }
216 sorted_alaw[j] = i;
217 }
218
219
220 for (i = 0; i < 256; i++) {
221
222 spl = i;
223 if (dsp_options & DSP_OPT_ULAW)
224 spl = dsp_audio_ulaw_to_alaw[i];
225
226 for (j = 0; j < 256; j++) {
227 if (sorted_alaw[j] == spl)
228 break;
229 }
230
231 dsp_audio_law2seven[i] = j >> 1;
232 }
233 for (i = 0; i < 128; i++) {
234 spl = sorted_alaw[i << 1];
235 if (dsp_options & DSP_OPT_ULAW)
236 spl = dsp_audio_alaw_to_ulaw[spl];
237 dsp_audio_seven2law[i] = spl;
238 }
239}
240
241
242
243u8 dsp_audio_mix_law[65536];
244
245
246
247
248
249void
250dsp_audio_generate_mix_table(void)
251{
252 int i, j;
253 s32 sample;
254
255 i = 0;
256 while (i < 256) {
257 j = 0;
258 while (j < 256) {
259 sample = dsp_audio_law_to_s32[i];
260 sample += dsp_audio_law_to_s32[j];
261 if (sample > 32767)
262 sample = 32767;
263 if (sample < -32768)
264 sample = -32768;
265 dsp_audio_mix_law[(i<<8)|j] =
266 dsp_audio_s16_to_law[sample & 0xffff];
267 j++;
268 }
269 i++;
270 }
271}
272
273
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276
277
278static u8 dsp_audio_reduce8[256];
279static u8 dsp_audio_reduce7[256];
280static u8 dsp_audio_reduce6[256];
281static u8 dsp_audio_reduce5[256];
282static u8 dsp_audio_reduce4[256];
283static u8 dsp_audio_reduce3[256];
284static u8 dsp_audio_reduce2[256];
285static u8 dsp_audio_reduce1[256];
286static u8 dsp_audio_increase1[256];
287static u8 dsp_audio_increase2[256];
288static u8 dsp_audio_increase3[256];
289static u8 dsp_audio_increase4[256];
290static u8 dsp_audio_increase5[256];
291static u8 dsp_audio_increase6[256];
292static u8 dsp_audio_increase7[256];
293static u8 dsp_audio_increase8[256];
294
295static u8 *dsp_audio_volume_change[16] = {
296 dsp_audio_reduce8,
297 dsp_audio_reduce7,
298 dsp_audio_reduce6,
299 dsp_audio_reduce5,
300 dsp_audio_reduce4,
301 dsp_audio_reduce3,
302 dsp_audio_reduce2,
303 dsp_audio_reduce1,
304 dsp_audio_increase1,
305 dsp_audio_increase2,
306 dsp_audio_increase3,
307 dsp_audio_increase4,
308 dsp_audio_increase5,
309 dsp_audio_increase6,
310 dsp_audio_increase7,
311 dsp_audio_increase8,
312};
313
314void
315dsp_audio_generate_volume_changes(void)
316{
317 register s32 sample;
318 int i;
319 int num[] = { 110, 125, 150, 175, 200, 300, 400, 500 };
320 int denum[] = { 100, 100, 100, 100, 100, 100, 100, 100 };
321
322 i = 0;
323 while (i < 256) {
324 dsp_audio_reduce8[i] = dsp_audio_s16_to_law[
325 (dsp_audio_law_to_s32[i] * denum[7] / num[7]) & 0xffff];
326 dsp_audio_reduce7[i] = dsp_audio_s16_to_law[
327 (dsp_audio_law_to_s32[i] * denum[6] / num[6]) & 0xffff];
328 dsp_audio_reduce6[i] = dsp_audio_s16_to_law[
329 (dsp_audio_law_to_s32[i] * denum[5] / num[5]) & 0xffff];
330 dsp_audio_reduce5[i] = dsp_audio_s16_to_law[
331 (dsp_audio_law_to_s32[i] * denum[4] / num[4]) & 0xffff];
332 dsp_audio_reduce4[i] = dsp_audio_s16_to_law[
333 (dsp_audio_law_to_s32[i] * denum[3] / num[3]) & 0xffff];
334 dsp_audio_reduce3[i] = dsp_audio_s16_to_law[
335 (dsp_audio_law_to_s32[i] * denum[2] / num[2]) & 0xffff];
336 dsp_audio_reduce2[i] = dsp_audio_s16_to_law[
337 (dsp_audio_law_to_s32[i] * denum[1] / num[1]) & 0xffff];
338 dsp_audio_reduce1[i] = dsp_audio_s16_to_law[
339 (dsp_audio_law_to_s32[i] * denum[0] / num[0]) & 0xffff];
340 sample = dsp_audio_law_to_s32[i] * num[0] / denum[0];
341 if (sample < -32768)
342 sample = -32768;
343 else if (sample > 32767)
344 sample = 32767;
345 dsp_audio_increase1[i] = dsp_audio_s16_to_law[sample & 0xffff];
346 sample = dsp_audio_law_to_s32[i] * num[1] / denum[1];
347 if (sample < -32768)
348 sample = -32768;
349 else if (sample > 32767)
350 sample = 32767;
351 dsp_audio_increase2[i] = dsp_audio_s16_to_law[sample & 0xffff];
352 sample = dsp_audio_law_to_s32[i] * num[2] / denum[2];
353 if (sample < -32768)
354 sample = -32768;
355 else if (sample > 32767)
356 sample = 32767;
357 dsp_audio_increase3[i] = dsp_audio_s16_to_law[sample & 0xffff];
358 sample = dsp_audio_law_to_s32[i] * num[3] / denum[3];
359 if (sample < -32768)
360 sample = -32768;
361 else if (sample > 32767)
362 sample = 32767;
363 dsp_audio_increase4[i] = dsp_audio_s16_to_law[sample & 0xffff];
364 sample = dsp_audio_law_to_s32[i] * num[4] / denum[4];
365 if (sample < -32768)
366 sample = -32768;
367 else if (sample > 32767)
368 sample = 32767;
369 dsp_audio_increase5[i] = dsp_audio_s16_to_law[sample & 0xffff];
370 sample = dsp_audio_law_to_s32[i] * num[5] / denum[5];
371 if (sample < -32768)
372 sample = -32768;
373 else if (sample > 32767)
374 sample = 32767;
375 dsp_audio_increase6[i] = dsp_audio_s16_to_law[sample & 0xffff];
376 sample = dsp_audio_law_to_s32[i] * num[6] / denum[6];
377 if (sample < -32768)
378 sample = -32768;
379 else if (sample > 32767)
380 sample = 32767;
381 dsp_audio_increase7[i] = dsp_audio_s16_to_law[sample & 0xffff];
382 sample = dsp_audio_law_to_s32[i] * num[7] / denum[7];
383 if (sample < -32768)
384 sample = -32768;
385 else if (sample > 32767)
386 sample = 32767;
387 dsp_audio_increase8[i] = dsp_audio_s16_to_law[sample & 0xffff];
388
389 i++;
390 }
391}
392
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397
398
399
400
401void
402dsp_change_volume(struct sk_buff *skb, int volume)
403{
404 u8 *volume_change;
405 int i, ii;
406 u8 *p;
407 int shift;
408
409 if (volume == 0)
410 return;
411
412
413 if (volume < 0) {
414 shift = volume + 8;
415 if (shift < 0)
416 shift = 0;
417 } else {
418 shift = volume + 7;
419 if (shift > 15)
420 shift = 15;
421 }
422 volume_change = dsp_audio_volume_change[shift];
423 i = 0;
424 ii = skb->len;
425 p = skb->data;
426
427 while (i < ii) {
428 *p = volume_change[*p];
429 p++;
430 i++;
431 }
432}
433
434