comparison spandsp-0.0.6pre17/src/gsm0610_long_term.c @ 4:26cd8f1ef0b1

import spandsp-0.0.6pre17
author Peter Meerwald <pmeerw@cosy.sbg.ac.at>
date Fri, 25 Jun 2010 15:50:58 +0200
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3:c6c5a16ce2f2 4:26cd8f1ef0b1
1 /*
2 * SpanDSP - a series of DSP components for telephony
3 *
4 * gsm0610_long_term.c - GSM 06.10 full rate speech codec.
5 *
6 * Written by Steve Underwood <steveu@coppice.org>
7 *
8 * Copyright (C) 2006 Steve Underwood
9 *
10 * All rights reserved.
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU Lesser General Public License version 2.1,
14 * as published by the Free Software Foundation.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU Lesser General Public License for more details.
20 *
21 * You should have received a copy of the GNU Lesser General Public
22 * License along with this program; if not, write to the Free Software
23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 *
25 * This code is based on the widely used GSM 06.10 code available from
26 * http://kbs.cs.tu-berlin.de/~jutta/toast.html
27 *
28 * $Id: gsm0610_long_term.c,v 1.24 2009/04/20 16:36:36 steveu Exp $
29 */
30
31 /*! \file */
32
33 #if defined(HAVE_CONFIG_H)
34 #include "config.h"
35 #endif
36
37 #include <assert.h>
38 #include <inttypes.h>
39 #if defined(HAVE_TGMATH_H)
40 #include <tgmath.h>
41 #endif
42 #if defined(HAVE_MATH_H)
43 #include <math.h>
44 #endif
45 #include "floating_fudge.h"
46 #include <stdlib.h>
47
48 #include "spandsp/telephony.h"
49 #include "spandsp/fast_convert.h"
50 #include "spandsp/bitstream.h"
51 #include "spandsp/saturated.h"
52 #include "spandsp/gsm0610.h"
53
54 #include "gsm0610_local.h"
55
56 /* Table 4.3a Decision level of the LTP gain quantizer */
57 static const int16_t gsm_DLB[4] =
58 {
59 6554, 16384, 26214, 32767
60 };
61
62 /* Table 4.3b Quantization levels of the LTP gain quantizer */
63 static const int16_t gsm_QLB[4] =
64 {
65 3277, 11469, 21299, 32767
66 };
67
68 /* 4.2.11 .. 4.2.12 LONG TERM PREDICTOR (LTP) SECTION */
69
70 static int32_t gsm0610_max_cross_corr(const int16_t *wt, const int16_t *dp, int16_t *index_out)
71 {
72 int32_t max;
73 int32_t index;
74 int32_t res;
75 int i;
76
77 max = 0;
78 index = 40; /* index for the maximum cross-correlation */
79
80 for (i = 40; i <= 120; i++)
81 {
82 #if defined(__GNUC__) && defined(SPANDSP_USE_MMX) && defined(__x86_64__)
83 __asm__ __volatile__(
84 " emms;\n"
85 " .p2align 2;\n"
86 " movq (%%rdi),%%mm0;\n"
87 " movq (%%rsi),%%mm2;\n"
88 " pmaddwd %%mm2,%%mm0;\n"
89 " movq 8(%%rdi),%%mm1;\n"
90 " movq 8(%%rsi),%%mm2;\n"
91 " pmaddwd %%mm2,%%mm1;\n"
92 " paddd %%mm1,%%mm0;\n"
93 " movq 16(%%rdi),%%mm1;\n"
94 " movq 16(%%rsi),%%mm2;\n"
95 " pmaddwd %%mm2,%%mm1;\n"
96 " paddd %%mm1,%%mm0;\n"
97 " movq 24(%%rdi),%%mm1;\n"
98 " movq 24(%%rsi),%%mm2;\n"
99 " pmaddwd %%mm2,%%mm1;\n"
100 " paddd %%mm1,%%mm0;\n"
101 " movq 32(%%rdi),%%mm1;\n"
102 " movq 32(%%rsi),%%mm2;\n"
103 " pmaddwd %%mm2,%%mm1;\n"
104 " paddd %%mm1,%%mm0;\n"
105 " movq 40(%%rdi),%%mm1;\n"
106 " movq 40(%%rsi),%%mm2;\n"
107 " pmaddwd %%mm2,%%mm1;\n"
108 " paddd %%mm1,%%mm0;\n"
109 " movq 48(%%rdi),%%mm1;\n"
110 " movq 48(%%rsi),%%mm2;\n"
111 " pmaddwd %%mm2,%%mm1;\n"
112 " paddd %%mm1,%%mm0;\n"
113 " movq 56(%%rdi),%%mm1;\n"
114 " movq 56(%%rsi),%%mm2;\n"
115 " pmaddwd %%mm2,%%mm1;\n"
116 " paddd %%mm1,%%mm0;\n"
117 " movq 64(%%rdi),%%mm1;\n"
118 " movq 64(%%rsi),%%mm2;\n"
119 " pmaddwd %%mm2,%%mm1;\n"
120 " paddd %%mm1,%%mm0;\n"
121 " movq 72(%%rdi),%%mm1;\n"
122 " movq 72(%%rsi),%%mm2;\n"
123 " pmaddwd %%mm2,%%mm1;\n"
124 " paddd %%mm1,%%mm0;\n"
125 " movq %%mm0,%%mm1;\n"
126 " punpckhdq %%mm0,%%mm1;\n" /* mm1 has high int32 of mm0 dup'd */
127 " paddd %%mm1,%%mm0;\n"
128 " movd %%mm0,%[res];\n"
129 " emms;\n"
130 : [res] "=r" (res)
131 : "D" (wt), "S" (&dp[-i])
132 );
133 #elif defined(__GNUC__) && defined(SPANDSP_USE_MMX) && defined(__i386__)
134 __asm__ __volatile__(
135 " emms;\n"
136 " .p2align 2;\n"
137 " movq (%%edi),%%mm0;\n"
138 " movq (%%esi),%%mm2;\n"
139 " pmaddwd %%mm2,%%mm0;\n"
140 " movq 8(%%edi),%%mm1;\n"
141 " movq 8(%%esi),%%mm2;\n"
142 " pmaddwd %%mm2,%%mm1;\n"
143 " paddd %%mm1,%%mm0;\n"
144 " movq 16(%%edi),%%mm1;\n"
145 " movq 16(%%esi),%%mm2;\n"
146 " pmaddwd %%mm2,%%mm1;\n"
147 " paddd %%mm1,%%mm0;\n"
148 " movq 24(%%edi),%%mm1;\n"
149 " movq 24(%%esi),%%mm2;\n"
150 " pmaddwd %%mm2,%%mm1;\n"
151 " paddd %%mm1,%%mm0;\n"
152 " movq 32(%%edi),%%mm1;\n"
153 " movq 32(%%esi),%%mm2;\n"
154 " pmaddwd %%mm2,%%mm1;\n"
155 " paddd %%mm1,%%mm0;\n"
156 " movq 40(%%edi),%%mm1;\n"
157 " movq 40(%%esi),%%mm2;\n"
158 " pmaddwd %%mm2,%%mm1;\n"
159 " paddd %%mm1,%%mm0;\n"
160 " movq 48(%%edi),%%mm1;\n"
161 " movq 48(%%esi),%%mm2;\n"
162 " pmaddwd %%mm2,%%mm1;\n"
163 " paddd %%mm1,%%mm0;\n"
164 " movq 56(%%edi),%%mm1;\n"
165 " movq 56(%%esi),%%mm2;\n"
166 " pmaddwd %%mm2,%%mm1;\n"
167 " paddd %%mm1,%%mm0;\n"
168 " movq 64(%%edi),%%mm1;\n"
169 " movq 64(%%esi),%%mm2;\n"
170 " pmaddwd %%mm2,%%mm1;\n"
171 " paddd %%mm1,%%mm0;\n"
172 " movq 72(%%edi),%%mm1;\n"
173 " movq 72(%%esi),%%mm2;\n"
174 " pmaddwd %%mm2,%%mm1;\n"
175 " paddd %%mm1,%%mm0;\n"
176 " movq %%mm0,%%mm1;\n"
177 " punpckhdq %%mm0,%%mm1;\n" /* mm1 has high int32 of mm0 dup'd */
178 " paddd %%mm1,%%mm0;\n"
179 " movd %%mm0,%[res];\n"
180 " emms;\n"
181 : [res] "=r" (res)
182 : "D" (wt), "S" (&dp[-i])
183 );
184 #else
185 res = (wt[0]*dp[0 - i])
186 + (wt[1]*dp[1 - i])
187 + (wt[2]*dp[2 - i])
188 + (wt[3]*dp[3 - i])
189 + (wt[4]*dp[4 - i])
190 + (wt[5]*dp[5 - i])
191 + (wt[6]*dp[6 - i])
192 + (wt[7]*dp[7 - i])
193 + (wt[8]*dp[8 - i])
194 + (wt[9]*dp[9 - i])
195 + (wt[10]*dp[10 - i])
196 + (wt[11]*dp[11 - i])
197 + (wt[12]*dp[12 - i])
198 + (wt[13]*dp[13 - i])
199 + (wt[14]*dp[14 - i])
200 + (wt[15]*dp[15 - i])
201 + (wt[16]*dp[16 - i])
202 + (wt[17]*dp[17 - i])
203 + (wt[18]*dp[18 - i])
204 + (wt[19]*dp[19 - i])
205 + (wt[20]*dp[20 - i])
206 + (wt[21]*dp[21 - i])
207 + (wt[22]*dp[22 - i])
208 + (wt[23]*dp[23 - i])
209 + (wt[24]*dp[24 - i])
210 + (wt[25]*dp[25 - i])
211 + (wt[26]*dp[26 - i])
212 + (wt[27]*dp[27 - i])
213 + (wt[28]*dp[28 - i])
214 + (wt[29]*dp[29 - i])
215 + (wt[30]*dp[30 - i])
216 + (wt[31]*dp[31 - i])
217 + (wt[32]*dp[32 - i])
218 + (wt[33]*dp[33 - i])
219 + (wt[34]*dp[34 - i])
220 + (wt[35]*dp[35 - i])
221 + (wt[36]*dp[36 - i])
222 + (wt[37]*dp[37 - i])
223 + (wt[38]*dp[38 - i])
224 + (wt[39]*dp[39 - i]);
225 #endif
226 if (res > max)
227 {
228 max = res;
229 index = i;
230 }
231 /*endif*/
232 }
233 /*endfor*/
234 *index_out = index;
235 return max;
236 }
237 /*- End of function --------------------------------------------------------*/
238
239 /* This procedure computes the LTP gain (bc) and the LTP lag (Nc)
240 for the long term analysis filter. This is done by calculating a
241 maximum of the cross-correlation function between the current
242 sub-segment short term residual signal d[0..39] (output of
243 the short term analysis filter; for simplification the index
244 of this array begins at 0 and ends at 39 for each sub-segment of the
245 RPE-LTP analysis) and the previous reconstructed short term
246 residual signal dp[ -120 .. -1 ]. A dynamic scaling must be
247 performed to avoid overflow. */
248
249 /* This procedure exists in three versions. First, the integer
250 version; then, the two floating point versions (as another
251 function), with or without scaling. */
252
253 static int16_t evaluate_ltp_parameters(int16_t d[40],
254 int16_t *dp, // [-120..-1] IN
255 int16_t *Nc_out)
256 {
257 int k;
258 int16_t bc;
259 int16_t wt[40];
260 int32_t L_max;
261 int32_t L_power;
262 int16_t R;
263 int16_t S;
264 int16_t dmax;
265 int16_t scale;
266 int16_t temp;
267 int32_t L_temp;
268
269 /* Search of the optimum scaling of d[0..39]. */
270 dmax = 0;
271 for (k = 0; k < 40; k++)
272 {
273 temp = d[k];
274 temp = saturated_abs16(temp);
275 if (temp > dmax)
276 dmax = temp;
277 /*endif*/
278 }
279 /*endfor*/
280
281 if (dmax == 0)
282 {
283 temp = 0;
284 }
285 else
286 {
287 assert(dmax > 0);
288 temp = gsm0610_norm((int32_t) dmax << 16);
289 }
290 /*endif*/
291
292 if (temp > 6)
293 scale = 0;
294 else
295 scale = (int16_t) (6 - temp);
296 /*endif*/
297 assert(scale >= 0);
298
299 /* Initialization of a working array wt */
300 for (k = 0; k < 40; k++)
301 wt[k] = d[k] >> scale;
302 /*endfor*/
303
304 /* Search for the maximum cross-correlation and coding of the LTP lag */
305 L_max = gsm0610_max_cross_corr(wt, dp, Nc_out);
306 L_max <<= 1;
307
308 /* Rescaling of L_max */
309 assert(scale <= 100 && scale >= -100);
310 L_max = L_max >> (6 - scale);
311
312 assert(*Nc_out <= 120 && *Nc_out >= 40);
313
314 /* Compute the power of the reconstructed short term residual signal dp[..] */
315 L_power = 0;
316 for (k = 0; k < 40; k++)
317 {
318 L_temp = dp[k - *Nc_out] >> 3;
319 L_power += L_temp*L_temp;
320 }
321 /*endfor*/
322 L_power <<= 1; /* from L_MULT */
323
324 /* Normalization of L_max and L_power */
325 if (L_max <= 0)
326 return 0;
327 /*endif*/
328 if (L_max >= L_power)
329 return 3;
330 /*endif*/
331 temp = gsm0610_norm(L_power);
332
333 R = (int16_t) ((L_max << temp) >> 16);
334 S = (int16_t) ((L_power << temp) >> 16);
335
336 /* Coding of the LTP gain */
337
338 /* Table 4.3a must be used to obtain the level DLB[i] for the
339 quantization of the LTP gain b to get the coded version bc. */
340 for (bc = 0; bc <= 2; bc++)
341 {
342 if (R <= saturated_mul16(S, gsm_DLB[bc]))
343 break;
344 /*endif*/
345 }
346 /*endfor*/
347 return bc;
348 }
349 /*- End of function --------------------------------------------------------*/
350
351 /* 4.2.12 */
352 static void long_term_analysis_filtering(int16_t bc,
353 int16_t Nc,
354 int16_t *dp, // previous d [-120..-1] IN
355 int16_t d[40],
356 int16_t dpp[40],
357 int16_t e[40])
358 {
359 int k;
360
361 /* In this part, we have to decode the bc parameter to compute
362 the samples of the estimate dpp[0..39]. The decoding of bc needs the
363 use of table 4.3b. The long term residual signal e[0..39]
364 is then calculated to be fed to the RPE encoding section. */
365 for (k = 0; k < 40; k++)
366 {
367 dpp[k] = gsm_mult_r(gsm_QLB[bc], dp[k - Nc]);
368 e[k] = saturated_sub16(d[k], dpp[k]);
369 }
370 /*endfor*/
371 }
372 /*- End of function --------------------------------------------------------*/
373
374 /* 4x for 160 samples */
375 void gsm0610_long_term_predictor(gsm0610_state_t *s,
376 int16_t d[40],
377 int16_t *dp, // [-120..-1] d' IN
378 int16_t e[40],
379 int16_t dpp[40],
380 int16_t *Nc,
381 int16_t *bc)
382 {
383 #if 0
384 assert(d);
385 assert(dp);
386 assert(e);
387 assert(dpp);
388 assert(Nc);
389 assert(bc);
390 #endif
391
392 *bc = evaluate_ltp_parameters(d, dp, Nc);
393 long_term_analysis_filtering(*bc, *Nc, dp, d, dpp, e);
394 }
395 /*- End of function --------------------------------------------------------*/
396
397 /* 4.3.2 */
398 void gsm0610_long_term_synthesis_filtering(gsm0610_state_t *s,
399 int16_t Ncr,
400 int16_t bcr,
401 int16_t erp[40],
402 int16_t *drp) // [-120..-1] IN, [0..40] OUT
403 {
404 int k;
405 int16_t brp;
406 int16_t drpp;
407 int16_t Nr;
408
409 /* This procedure uses the bcr and Ncr parameters to realize the
410 long term synthesis filter. The decoding of bcr needs
411 table 4.3b. */
412
413 /* Check the limits of Nr. */
414 Nr = (Ncr < 40 || Ncr > 120) ? s->nrp : Ncr;
415 s->nrp = Nr;
416 assert (Nr >= 40 && Nr <= 120);
417
418 /* Decode the LTP gain, bcr */
419 brp = gsm_QLB[bcr];
420
421 /* Compute the reconstructed short term residual signal, drp[0..39] */
422 assert(brp != INT16_MIN);
423 for (k = 0; k < 40; k++)
424 {
425 drpp = gsm_mult_r(brp, drp[k - Nr]);
426 drp[k] = saturated_add16(erp[k], drpp);
427 }
428 /*endfor*/
429
430 /* Update the reconstructed short term residual signal, drp[-1..-120] */
431 for (k = 0; k < 120; k++)
432 drp[k - 120] = drp[k - 80];
433 /*endfor*/
434 }
435 /*- End of function --------------------------------------------------------*/
436 /*- End of file ------------------------------------------------------------*/

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