1 /* libFLAC - Free Lossless Audio Codec library
2  * Copyright (C) 2000-2009  Josh Coalson
3  * Copyright (C) 2011-2014  Xiph.Org Foundation
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *
9  * - Redistributions of source code must retain the above copyright
10  * notice, this list of conditions and the following disclaimer.
11  *
12  * - Redistributions in binary form must reproduce the above copyright
13  * notice, this list of conditions and the following disclaimer in the
14  * documentation and/or other materials provided with the distribution.
15  *
16  * - Neither the name of the Xiph.org Foundation nor the names of its
17  * contributors may be used to endorse or promote products derived from
18  * this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23  * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
24  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
25  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
26  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
27  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
28  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
29  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
30  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #ifdef HAVE_CONFIG_H
34 #  include <config.h>
35 #endif
36 
37 #include <math.h>
38 
39 #include "FLAC/assert.h"
40 #include "FLAC/format.h"
41 #include "share/compat.h"
42 #include "private/bitmath.h"
43 #include "private/lpc.h"
44 #include "private/macros.h"
45 #if defined DEBUG || defined FLAC__OVERFLOW_DETECT || defined FLAC__OVERFLOW_DETECT_VERBOSE
46 #include <stdio.h>
47 #endif
48 
49 /* OPT: #undef'ing this may improve the speed on some architectures */
50 #define FLAC__LPC_UNROLLED_FILTER_LOOPS
51 
52 #ifndef FLAC__INTEGER_ONLY_LIBRARY
53 
54 #if !defined(HAVE_LROUND)
55 #if defined(_MSC_VER)
56 #include <float.h>
57 #define copysign _copysign
58 #elif defined(__GNUC__)
59 #define copysign __builtin_copysign
60 #endif
lround(double x)61 static inline long int lround(double x) {
62     return (long)(x + copysign (0.5, x));
63 }
64 /* If this fails, we are in the presence of a mid 90's compiler, move along... */
65 #endif
66 
FLAC__lpc_window_data(const FLAC__int32 in[],const FLAC__real window[],FLAC__real out[],unsigned data_len)67 void FLAC__lpc_window_data(const FLAC__int32 in[], const FLAC__real window[], FLAC__real out[], unsigned data_len)
68 {
69 	unsigned i;
70 	for(i = 0; i < data_len; i++)
71 		out[i] = in[i] * window[i];
72 }
73 
FLAC__lpc_compute_autocorrelation(const FLAC__real data[],unsigned data_len,unsigned lag,FLAC__real autoc[])74 void FLAC__lpc_compute_autocorrelation(const FLAC__real data[], unsigned data_len, unsigned lag, FLAC__real autoc[])
75 {
76 	/* a readable, but slower, version */
77 #if 0
78 	FLAC__real d;
79 	unsigned i;
80 
81 	FLAC__ASSERT(lag > 0);
82 	FLAC__ASSERT(lag <= data_len);
83 
84 	/*
85 	 * Technically we should subtract the mean first like so:
86 	 *   for(i = 0; i < data_len; i++)
87 	 *     data[i] -= mean;
88 	 * but it appears not to make enough of a difference to matter, and
89 	 * most signals are already closely centered around zero
90 	 */
91 	while(lag--) {
92 		for(i = lag, d = 0.0; i < data_len; i++)
93 			d += data[i] * data[i - lag];
94 		autoc[lag] = d;
95 	}
96 #endif
97 
98 	/*
99 	 * this version tends to run faster because of better data locality
100 	 * ('data_len' is usually much larger than 'lag')
101 	 */
102 	FLAC__real d;
103 	unsigned sample, coeff;
104 	const unsigned limit = data_len - lag;
105 
106 	FLAC__ASSERT(lag > 0);
107 	FLAC__ASSERT(lag <= data_len);
108 
109 	for(coeff = 0; coeff < lag; coeff++)
110 		autoc[coeff] = 0.0;
111 	for(sample = 0; sample <= limit; sample++) {
112 		d = data[sample];
113 		for(coeff = 0; coeff < lag; coeff++)
114 			autoc[coeff] += d * data[sample+coeff];
115 	}
116 	for(; sample < data_len; sample++) {
117 		d = data[sample];
118 		for(coeff = 0; coeff < data_len - sample; coeff++)
119 			autoc[coeff] += d * data[sample+coeff];
120 	}
121 }
122 
FLAC__lpc_compute_lp_coefficients(const FLAC__real autoc[],unsigned * max_order,FLAC__real lp_coeff[][FLAC__MAX_LPC_ORDER],FLAC__double error[])123 void FLAC__lpc_compute_lp_coefficients(const FLAC__real autoc[], unsigned *max_order, FLAC__real lp_coeff[][FLAC__MAX_LPC_ORDER], FLAC__double error[])
124 {
125 	unsigned i, j;
126 	FLAC__double r, err, lpc[FLAC__MAX_LPC_ORDER];
127 
128 	FLAC__ASSERT(0 != max_order);
129 	FLAC__ASSERT(0 < *max_order);
130 	FLAC__ASSERT(*max_order <= FLAC__MAX_LPC_ORDER);
131 	FLAC__ASSERT(autoc[0] != 0.0);
132 
133 	err = autoc[0];
134 
135 	for(i = 0; i < *max_order; i++) {
136 		/* Sum up this iteration's reflection coefficient. */
137 		r = -autoc[i+1];
138 		for(j = 0; j < i; j++)
139 			r -= lpc[j] * autoc[i-j];
140 		r /= err;
141 
142 		/* Update LPC coefficients and total error. */
143 		lpc[i]=r;
144 		for(j = 0; j < (i>>1); j++) {
145 			FLAC__double tmp = lpc[j];
146 			lpc[j] += r * lpc[i-1-j];
147 			lpc[i-1-j] += r * tmp;
148 		}
149 		if(i & 1)
150 			lpc[j] += lpc[j] * r;
151 
152 		err *= (1.0 - r * r);
153 
154 		/* save this order */
155 		for(j = 0; j <= i; j++)
156 			lp_coeff[i][j] = (FLAC__real)(-lpc[j]); /* negate FIR filter coeff to get predictor coeff */
157 		error[i] = err;
158 
159 		/* see SF bug https://sourceforge.net/p/flac/bugs/234/ */
160 		if(err == 0.0) {
161 			*max_order = i+1;
162 			return;
163 		}
164 	}
165 }
166 
FLAC__lpc_quantize_coefficients(const FLAC__real lp_coeff[],unsigned order,unsigned precision,FLAC__int32 qlp_coeff[],int * shift)167 int FLAC__lpc_quantize_coefficients(const FLAC__real lp_coeff[], unsigned order, unsigned precision, FLAC__int32 qlp_coeff[], int *shift)
168 {
169 	unsigned i;
170 	FLAC__double cmax;
171 	FLAC__int32 qmax, qmin;
172 
173 	FLAC__ASSERT(precision > 0);
174 	FLAC__ASSERT(precision >= FLAC__MIN_QLP_COEFF_PRECISION);
175 
176 	/* drop one bit for the sign; from here on out we consider only |lp_coeff[i]| */
177 	precision--;
178 	qmax = 1 << precision;
179 	qmin = -qmax;
180 	qmax--;
181 
182 	/* calc cmax = max( |lp_coeff[i]| ) */
183 	cmax = 0.0;
184 	for(i = 0; i < order; i++) {
185 		const FLAC__double d = fabs(lp_coeff[i]);
186 		if(d > cmax)
187 			cmax = d;
188 	}
189 
190 	if(cmax <= 0.0) {
191 		/* => coefficients are all 0, which means our constant-detect didn't work */
192 		return 2;
193 	}
194 	else {
195 		const int max_shiftlimit = (1 << (FLAC__SUBFRAME_LPC_QLP_SHIFT_LEN-1)) - 1;
196 		const int min_shiftlimit = -max_shiftlimit - 1;
197 		int log2cmax;
198 
199 		(void)frexp(cmax, &log2cmax);
200 		log2cmax--;
201 		*shift = (int)precision - log2cmax - 1;
202 
203 		if(*shift > max_shiftlimit)
204 			*shift = max_shiftlimit;
205 		else if(*shift < min_shiftlimit)
206 			return 1;
207 	}
208 
209 	if(*shift >= 0) {
210 		FLAC__double error = 0.0;
211 		FLAC__int32 q;
212 		for(i = 0; i < order; i++) {
213 			error += lp_coeff[i] * (1 << *shift);
214 			q = lround(error);
215 
216 #ifdef FLAC__OVERFLOW_DETECT
217 			if(q > qmax+1) /* we expect q==qmax+1 occasionally due to rounding */
218 				fprintf(stderr,"FLAC__lpc_quantize_coefficients: quantizer overflow: q>qmax %d>%d shift=%d cmax=%f precision=%u lpc[%u]=%f\n",q,qmax,*shift,cmax,precision+1,i,lp_coeff[i]);
219 			else if(q < qmin)
220 				fprintf(stderr,"FLAC__lpc_quantize_coefficients: quantizer overflow: q<qmin %d<%d shift=%d cmax=%f precision=%u lpc[%u]=%f\n",q,qmin,*shift,cmax,precision+1,i,lp_coeff[i]);
221 #endif
222 			if(q > qmax)
223 				q = qmax;
224 			else if(q < qmin)
225 				q = qmin;
226 			error -= q;
227 			qlp_coeff[i] = q;
228 		}
229 	}
230 	/* negative shift is very rare but due to design flaw, negative shift is
231 	 * a NOP in the decoder, so it must be handled specially by scaling down
232 	 * coeffs
233 	 */
234 	else {
235 		const int nshift = -(*shift);
236 		FLAC__double error = 0.0;
237 		FLAC__int32 q;
238 #ifdef DEBUG
239 		fprintf(stderr,"FLAC__lpc_quantize_coefficients: negative shift=%d order=%u cmax=%f\n", *shift, order, cmax);
240 #endif
241 		for(i = 0; i < order; i++) {
242 			error += lp_coeff[i] / (1 << nshift);
243 			q = lround(error);
244 #ifdef FLAC__OVERFLOW_DETECT
245 			if(q > qmax+1) /* we expect q==qmax+1 occasionally due to rounding */
246 				fprintf(stderr,"FLAC__lpc_quantize_coefficients: quantizer overflow: q>qmax %d>%d shift=%d cmax=%f precision=%u lpc[%u]=%f\n",q,qmax,*shift,cmax,precision+1,i,lp_coeff[i]);
247 			else if(q < qmin)
248 				fprintf(stderr,"FLAC__lpc_quantize_coefficients: quantizer overflow: q<qmin %d<%d shift=%d cmax=%f precision=%u lpc[%u]=%f\n",q,qmin,*shift,cmax,precision+1,i,lp_coeff[i]);
249 #endif
250 			if(q > qmax)
251 				q = qmax;
252 			else if(q < qmin)
253 				q = qmin;
254 			error -= q;
255 			qlp_coeff[i] = q;
256 		}
257 		*shift = 0;
258 	}
259 
260 	return 0;
261 }
262 
263 #if defined(_MSC_VER)
264 // silence MSVC warnings about __restrict modifier
265 #pragma warning ( disable : 4028 )
266 #endif
267 
FLAC__lpc_compute_residual_from_qlp_coefficients(const FLAC__int32 * flac_restrict data,unsigned data_len,const FLAC__int32 * flac_restrict qlp_coeff,unsigned order,int lp_quantization,FLAC__int32 * flac_restrict residual)268 void FLAC__lpc_compute_residual_from_qlp_coefficients(const FLAC__int32 * flac_restrict data, unsigned data_len, const FLAC__int32 * flac_restrict qlp_coeff, unsigned order, int lp_quantization, FLAC__int32 * flac_restrict residual)
269 #if defined(FLAC__OVERFLOW_DETECT) || !defined(FLAC__LPC_UNROLLED_FILTER_LOOPS)
270 {
271 	FLAC__int64 sumo;
272 	unsigned i, j;
273 	FLAC__int32 sum;
274 	const FLAC__int32 *history;
275 
276 #ifdef FLAC__OVERFLOW_DETECT_VERBOSE
277 	fprintf(stderr,"FLAC__lpc_compute_residual_from_qlp_coefficients: data_len=%d, order=%u, lpq=%d",data_len,order,lp_quantization);
278 	for(i=0;i<order;i++)
279 		fprintf(stderr,", q[%u]=%d",i,qlp_coeff[i]);
280 	fprintf(stderr,"\n");
281 #endif
282 	FLAC__ASSERT(order > 0);
283 
284 	for(i = 0; i < data_len; i++) {
285 		sumo = 0;
286 		sum = 0;
287 		history = data;
288 		for(j = 0; j < order; j++) {
289 			sum += qlp_coeff[j] * (*(--history));
290 			sumo += (FLAC__int64)qlp_coeff[j] * (FLAC__int64)(*history);
291 			if(sumo > 2147483647ll || sumo < -2147483648ll)
292 				fprintf(stderr,"FLAC__lpc_compute_residual_from_qlp_coefficients: OVERFLOW, i=%u, j=%u, c=%d, d=%d, sumo=%" PRId64 "\n",i,j,qlp_coeff[j],*history,sumo);
293 		}
294 		*(residual++) = *(data++) - (sum >> lp_quantization);
295 	}
296 
297 	/* Here's a slower but clearer version:
298 	for(i = 0; i < data_len; i++) {
299 		sum = 0;
300 		for(j = 0; j < order; j++)
301 			sum += qlp_coeff[j] * data[i-j-1];
302 		residual[i] = data[i] - (sum >> lp_quantization);
303 	}
304 	*/
305 }
306 #else /* fully unrolled version for normal use */
307 {
308 	int i;
309 	FLAC__int32 sum;
310 
311 	FLAC__ASSERT(order > 0);
312 	FLAC__ASSERT(order <= 32);
313 
314 	/*
315 	 * We do unique versions up to 12th order since that's the subset limit.
316 	 * Also they are roughly ordered to match frequency of occurrence to
317 	 * minimize branching.
318 	 */
319 	if(order <= 12) {
320 		if(order > 8) {
321 			if(order > 10) {
322 				if(order == 12) {
323 					for(i = 0; i < (int)data_len; i++) {
324 						sum = 0;
325 						sum += qlp_coeff[11] * data[i-12];
326 						sum += qlp_coeff[10] * data[i-11];
327 						sum += qlp_coeff[9] * data[i-10];
328 						sum += qlp_coeff[8] * data[i-9];
329 						sum += qlp_coeff[7] * data[i-8];
330 						sum += qlp_coeff[6] * data[i-7];
331 						sum += qlp_coeff[5] * data[i-6];
332 						sum += qlp_coeff[4] * data[i-5];
333 						sum += qlp_coeff[3] * data[i-4];
334 						sum += qlp_coeff[2] * data[i-3];
335 						sum += qlp_coeff[1] * data[i-2];
336 						sum += qlp_coeff[0] * data[i-1];
337 						residual[i] = data[i] - (sum >> lp_quantization);
338 					}
339 				}
340 				else { /* order == 11 */
341 					for(i = 0; i < (int)data_len; i++) {
342 						sum = 0;
343 						sum += qlp_coeff[10] * data[i-11];
344 						sum += qlp_coeff[9] * data[i-10];
345 						sum += qlp_coeff[8] * data[i-9];
346 						sum += qlp_coeff[7] * data[i-8];
347 						sum += qlp_coeff[6] * data[i-7];
348 						sum += qlp_coeff[5] * data[i-6];
349 						sum += qlp_coeff[4] * data[i-5];
350 						sum += qlp_coeff[3] * data[i-4];
351 						sum += qlp_coeff[2] * data[i-3];
352 						sum += qlp_coeff[1] * data[i-2];
353 						sum += qlp_coeff[0] * data[i-1];
354 						residual[i] = data[i] - (sum >> lp_quantization);
355 					}
356 				}
357 			}
358 			else {
359 				if(order == 10) {
360 					for(i = 0; i < (int)data_len; i++) {
361 						sum = 0;
362 						sum += qlp_coeff[9] * data[i-10];
363 						sum += qlp_coeff[8] * data[i-9];
364 						sum += qlp_coeff[7] * data[i-8];
365 						sum += qlp_coeff[6] * data[i-7];
366 						sum += qlp_coeff[5] * data[i-6];
367 						sum += qlp_coeff[4] * data[i-5];
368 						sum += qlp_coeff[3] * data[i-4];
369 						sum += qlp_coeff[2] * data[i-3];
370 						sum += qlp_coeff[1] * data[i-2];
371 						sum += qlp_coeff[0] * data[i-1];
372 						residual[i] = data[i] - (sum >> lp_quantization);
373 					}
374 				}
375 				else { /* order == 9 */
376 					for(i = 0; i < (int)data_len; i++) {
377 						sum = 0;
378 						sum += qlp_coeff[8] * data[i-9];
379 						sum += qlp_coeff[7] * data[i-8];
380 						sum += qlp_coeff[6] * data[i-7];
381 						sum += qlp_coeff[5] * data[i-6];
382 						sum += qlp_coeff[4] * data[i-5];
383 						sum += qlp_coeff[3] * data[i-4];
384 						sum += qlp_coeff[2] * data[i-3];
385 						sum += qlp_coeff[1] * data[i-2];
386 						sum += qlp_coeff[0] * data[i-1];
387 						residual[i] = data[i] - (sum >> lp_quantization);
388 					}
389 				}
390 			}
391 		}
392 		else if(order > 4) {
393 			if(order > 6) {
394 				if(order == 8) {
395 					for(i = 0; i < (int)data_len; i++) {
396 						sum = 0;
397 						sum += qlp_coeff[7] * data[i-8];
398 						sum += qlp_coeff[6] * data[i-7];
399 						sum += qlp_coeff[5] * data[i-6];
400 						sum += qlp_coeff[4] * data[i-5];
401 						sum += qlp_coeff[3] * data[i-4];
402 						sum += qlp_coeff[2] * data[i-3];
403 						sum += qlp_coeff[1] * data[i-2];
404 						sum += qlp_coeff[0] * data[i-1];
405 						residual[i] = data[i] - (sum >> lp_quantization);
406 					}
407 				}
408 				else { /* order == 7 */
409 					for(i = 0; i < (int)data_len; i++) {
410 						sum = 0;
411 						sum += qlp_coeff[6] * data[i-7];
412 						sum += qlp_coeff[5] * data[i-6];
413 						sum += qlp_coeff[4] * data[i-5];
414 						sum += qlp_coeff[3] * data[i-4];
415 						sum += qlp_coeff[2] * data[i-3];
416 						sum += qlp_coeff[1] * data[i-2];
417 						sum += qlp_coeff[0] * data[i-1];
418 						residual[i] = data[i] - (sum >> lp_quantization);
419 					}
420 				}
421 			}
422 			else {
423 				if(order == 6) {
424 					for(i = 0; i < (int)data_len; i++) {
425 						sum = 0;
426 						sum += qlp_coeff[5] * data[i-6];
427 						sum += qlp_coeff[4] * data[i-5];
428 						sum += qlp_coeff[3] * data[i-4];
429 						sum += qlp_coeff[2] * data[i-3];
430 						sum += qlp_coeff[1] * data[i-2];
431 						sum += qlp_coeff[0] * data[i-1];
432 						residual[i] = data[i] - (sum >> lp_quantization);
433 					}
434 				}
435 				else { /* order == 5 */
436 					for(i = 0; i < (int)data_len; i++) {
437 						sum = 0;
438 						sum += qlp_coeff[4] * data[i-5];
439 						sum += qlp_coeff[3] * data[i-4];
440 						sum += qlp_coeff[2] * data[i-3];
441 						sum += qlp_coeff[1] * data[i-2];
442 						sum += qlp_coeff[0] * data[i-1];
443 						residual[i] = data[i] - (sum >> lp_quantization);
444 					}
445 				}
446 			}
447 		}
448 		else {
449 			if(order > 2) {
450 				if(order == 4) {
451 					for(i = 0; i < (int)data_len; i++) {
452 						sum = 0;
453 						sum += qlp_coeff[3] * data[i-4];
454 						sum += qlp_coeff[2] * data[i-3];
455 						sum += qlp_coeff[1] * data[i-2];
456 						sum += qlp_coeff[0] * data[i-1];
457 						residual[i] = data[i] - (sum >> lp_quantization);
458 					}
459 				}
460 				else { /* order == 3 */
461 					for(i = 0; i < (int)data_len; i++) {
462 						sum = 0;
463 						sum += qlp_coeff[2] * data[i-3];
464 						sum += qlp_coeff[1] * data[i-2];
465 						sum += qlp_coeff[0] * data[i-1];
466 						residual[i] = data[i] - (sum >> lp_quantization);
467 					}
468 				}
469 			}
470 			else {
471 				if(order == 2) {
472 					for(i = 0; i < (int)data_len; i++) {
473 						sum = 0;
474 						sum += qlp_coeff[1] * data[i-2];
475 						sum += qlp_coeff[0] * data[i-1];
476 						residual[i] = data[i] - (sum >> lp_quantization);
477 					}
478 				}
479 				else { /* order == 1 */
480 					for(i = 0; i < (int)data_len; i++)
481 						residual[i] = data[i] - ((qlp_coeff[0] * data[i-1]) >> lp_quantization);
482 				}
483 			}
484 		}
485 	}
486 	else { /* order > 12 */
487 		for(i = 0; i < (int)data_len; i++) {
488 			sum = 0;
489 			switch(order) {
490 				case 32: sum += qlp_coeff[31] * data[i-32];
491 				case 31: sum += qlp_coeff[30] * data[i-31];
492 				case 30: sum += qlp_coeff[29] * data[i-30];
493 				case 29: sum += qlp_coeff[28] * data[i-29];
494 				case 28: sum += qlp_coeff[27] * data[i-28];
495 				case 27: sum += qlp_coeff[26] * data[i-27];
496 				case 26: sum += qlp_coeff[25] * data[i-26];
497 				case 25: sum += qlp_coeff[24] * data[i-25];
498 				case 24: sum += qlp_coeff[23] * data[i-24];
499 				case 23: sum += qlp_coeff[22] * data[i-23];
500 				case 22: sum += qlp_coeff[21] * data[i-22];
501 				case 21: sum += qlp_coeff[20] * data[i-21];
502 				case 20: sum += qlp_coeff[19] * data[i-20];
503 				case 19: sum += qlp_coeff[18] * data[i-19];
504 				case 18: sum += qlp_coeff[17] * data[i-18];
505 				case 17: sum += qlp_coeff[16] * data[i-17];
506 				case 16: sum += qlp_coeff[15] * data[i-16];
507 				case 15: sum += qlp_coeff[14] * data[i-15];
508 				case 14: sum += qlp_coeff[13] * data[i-14];
509 				case 13: sum += qlp_coeff[12] * data[i-13];
510 				         sum += qlp_coeff[11] * data[i-12];
511 				         sum += qlp_coeff[10] * data[i-11];
512 				         sum += qlp_coeff[ 9] * data[i-10];
513 				         sum += qlp_coeff[ 8] * data[i- 9];
514 				         sum += qlp_coeff[ 7] * data[i- 8];
515 				         sum += qlp_coeff[ 6] * data[i- 7];
516 				         sum += qlp_coeff[ 5] * data[i- 6];
517 				         sum += qlp_coeff[ 4] * data[i- 5];
518 				         sum += qlp_coeff[ 3] * data[i- 4];
519 				         sum += qlp_coeff[ 2] * data[i- 3];
520 				         sum += qlp_coeff[ 1] * data[i- 2];
521 				         sum += qlp_coeff[ 0] * data[i- 1];
522 			}
523 			residual[i] = data[i] - (sum >> lp_quantization);
524 		}
525 	}
526 }
527 #endif
528 
FLAC__lpc_compute_residual_from_qlp_coefficients_wide(const FLAC__int32 * flac_restrict data,unsigned data_len,const FLAC__int32 * flac_restrict qlp_coeff,unsigned order,int lp_quantization,FLAC__int32 * flac_restrict residual)529 void FLAC__lpc_compute_residual_from_qlp_coefficients_wide(const FLAC__int32 * flac_restrict data, unsigned data_len, const FLAC__int32 * flac_restrict qlp_coeff, unsigned order, int lp_quantization, FLAC__int32 * flac_restrict residual)
530 #if defined(FLAC__OVERFLOW_DETECT) || !defined(FLAC__LPC_UNROLLED_FILTER_LOOPS)
531 {
532 	unsigned i, j;
533 	FLAC__int64 sum;
534 	const FLAC__int32 *history;
535 
536 #ifdef FLAC__OVERFLOW_DETECT_VERBOSE
537 	fprintf(stderr,"FLAC__lpc_compute_residual_from_qlp_coefficients_wide: data_len=%d, order=%u, lpq=%d",data_len,order,lp_quantization);
538 	for(i=0;i<order;i++)
539 		fprintf(stderr,", q[%u]=%d",i,qlp_coeff[i]);
540 	fprintf(stderr,"\n");
541 #endif
542 	FLAC__ASSERT(order > 0);
543 
544 	for(i = 0; i < data_len; i++) {
545 		sum = 0;
546 		history = data;
547 		for(j = 0; j < order; j++)
548 			sum += (FLAC__int64)qlp_coeff[j] * (FLAC__int64)(*(--history));
549 		if(FLAC__bitmath_silog2_wide(sum >> lp_quantization) > 32) {
550 			fprintf(stderr,"FLAC__lpc_compute_residual_from_qlp_coefficients_wide: OVERFLOW, i=%u, sum=%" PRId64 "\n", i, (sum >> lp_quantization));
551 			break;
552 		}
553 		if(FLAC__bitmath_silog2_wide((FLAC__int64)(*data) - (sum >> lp_quantization)) > 32) {
554 			fprintf(stderr,"FLAC__lpc_compute_residual_from_qlp_coefficients_wide: OVERFLOW, i=%u, data=%d, sum=%" PRId64 ", residual=%" PRId64 "\n", i, *data, (int64_t)(sum >> lp_quantization), ((FLAC__int64)(*data) - (sum >> lp_quantization)));
555 			break;
556 		}
557 		*(residual++) = *(data++) - (FLAC__int32)(sum >> lp_quantization);
558 	}
559 }
560 #else /* fully unrolled version for normal use */
561 {
562 	int i;
563 	FLAC__int64 sum;
564 
565 	FLAC__ASSERT(order > 0);
566 	FLAC__ASSERT(order <= 32);
567 
568 	/*
569 	 * We do unique versions up to 12th order since that's the subset limit.
570 	 * Also they are roughly ordered to match frequency of occurrence to
571 	 * minimize branching.
572 	 */
573 	if(order <= 12) {
574 		if(order > 8) {
575 			if(order > 10) {
576 				if(order == 12) {
577 					for(i = 0; i < (int)data_len; i++) {
578 						sum = 0;
579 						sum += qlp_coeff[11] * (FLAC__int64)data[i-12];
580 						sum += qlp_coeff[10] * (FLAC__int64)data[i-11];
581 						sum += qlp_coeff[9] * (FLAC__int64)data[i-10];
582 						sum += qlp_coeff[8] * (FLAC__int64)data[i-9];
583 						sum += qlp_coeff[7] * (FLAC__int64)data[i-8];
584 						sum += qlp_coeff[6] * (FLAC__int64)data[i-7];
585 						sum += qlp_coeff[5] * (FLAC__int64)data[i-6];
586 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
587 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
588 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
589 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
590 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
591 						residual[i] = data[i] - (FLAC__int32)(sum >> lp_quantization);
592 					}
593 				}
594 				else { /* order == 11 */
595 					for(i = 0; i < (int)data_len; i++) {
596 						sum = 0;
597 						sum += qlp_coeff[10] * (FLAC__int64)data[i-11];
598 						sum += qlp_coeff[9] * (FLAC__int64)data[i-10];
599 						sum += qlp_coeff[8] * (FLAC__int64)data[i-9];
600 						sum += qlp_coeff[7] * (FLAC__int64)data[i-8];
601 						sum += qlp_coeff[6] * (FLAC__int64)data[i-7];
602 						sum += qlp_coeff[5] * (FLAC__int64)data[i-6];
603 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
604 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
605 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
606 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
607 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
608 						residual[i] = data[i] - (FLAC__int32)(sum >> lp_quantization);
609 					}
610 				}
611 			}
612 			else {
613 				if(order == 10) {
614 					for(i = 0; i < (int)data_len; i++) {
615 						sum = 0;
616 						sum += qlp_coeff[9] * (FLAC__int64)data[i-10];
617 						sum += qlp_coeff[8] * (FLAC__int64)data[i-9];
618 						sum += qlp_coeff[7] * (FLAC__int64)data[i-8];
619 						sum += qlp_coeff[6] * (FLAC__int64)data[i-7];
620 						sum += qlp_coeff[5] * (FLAC__int64)data[i-6];
621 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
622 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
623 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
624 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
625 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
626 						residual[i] = data[i] - (FLAC__int32)(sum >> lp_quantization);
627 					}
628 				}
629 				else { /* order == 9 */
630 					for(i = 0; i < (int)data_len; i++) {
631 						sum = 0;
632 						sum += qlp_coeff[8] * (FLAC__int64)data[i-9];
633 						sum += qlp_coeff[7] * (FLAC__int64)data[i-8];
634 						sum += qlp_coeff[6] * (FLAC__int64)data[i-7];
635 						sum += qlp_coeff[5] * (FLAC__int64)data[i-6];
636 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
637 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
638 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
639 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
640 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
641 						residual[i] = data[i] - (FLAC__int32)(sum >> lp_quantization);
642 					}
643 				}
644 			}
645 		}
646 		else if(order > 4) {
647 			if(order > 6) {
648 				if(order == 8) {
649 					for(i = 0; i < (int)data_len; i++) {
650 						sum = 0;
651 						sum += qlp_coeff[7] * (FLAC__int64)data[i-8];
652 						sum += qlp_coeff[6] * (FLAC__int64)data[i-7];
653 						sum += qlp_coeff[5] * (FLAC__int64)data[i-6];
654 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
655 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
656 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
657 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
658 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
659 						residual[i] = data[i] - (FLAC__int32)(sum >> lp_quantization);
660 					}
661 				}
662 				else { /* order == 7 */
663 					for(i = 0; i < (int)data_len; i++) {
664 						sum = 0;
665 						sum += qlp_coeff[6] * (FLAC__int64)data[i-7];
666 						sum += qlp_coeff[5] * (FLAC__int64)data[i-6];
667 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
668 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
669 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
670 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
671 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
672 						residual[i] = data[i] - (FLAC__int32)(sum >> lp_quantization);
673 					}
674 				}
675 			}
676 			else {
677 				if(order == 6) {
678 					for(i = 0; i < (int)data_len; i++) {
679 						sum = 0;
680 						sum += qlp_coeff[5] * (FLAC__int64)data[i-6];
681 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
682 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
683 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
684 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
685 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
686 						residual[i] = data[i] - (FLAC__int32)(sum >> lp_quantization);
687 					}
688 				}
689 				else { /* order == 5 */
690 					for(i = 0; i < (int)data_len; i++) {
691 						sum = 0;
692 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
693 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
694 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
695 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
696 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
697 						residual[i] = data[i] - (FLAC__int32)(sum >> lp_quantization);
698 					}
699 				}
700 			}
701 		}
702 		else {
703 			if(order > 2) {
704 				if(order == 4) {
705 					for(i = 0; i < (int)data_len; i++) {
706 						sum = 0;
707 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
708 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
709 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
710 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
711 						residual[i] = data[i] - (FLAC__int32)(sum >> lp_quantization);
712 					}
713 				}
714 				else { /* order == 3 */
715 					for(i = 0; i < (int)data_len; i++) {
716 						sum = 0;
717 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
718 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
719 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
720 						residual[i] = data[i] - (FLAC__int32)(sum >> lp_quantization);
721 					}
722 				}
723 			}
724 			else {
725 				if(order == 2) {
726 					for(i = 0; i < (int)data_len; i++) {
727 						sum = 0;
728 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
729 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
730 						residual[i] = data[i] - (FLAC__int32)(sum >> lp_quantization);
731 					}
732 				}
733 				else { /* order == 1 */
734 					for(i = 0; i < (int)data_len; i++)
735 						residual[i] = data[i] - (FLAC__int32)((qlp_coeff[0] * (FLAC__int64)data[i-1]) >> lp_quantization);
736 				}
737 			}
738 		}
739 	}
740 	else { /* order > 12 */
741 		for(i = 0; i < (int)data_len; i++) {
742 			sum = 0;
743 			switch(order) {
744 				case 32: sum += qlp_coeff[31] * (FLAC__int64)data[i-32];
745 				case 31: sum += qlp_coeff[30] * (FLAC__int64)data[i-31];
746 				case 30: sum += qlp_coeff[29] * (FLAC__int64)data[i-30];
747 				case 29: sum += qlp_coeff[28] * (FLAC__int64)data[i-29];
748 				case 28: sum += qlp_coeff[27] * (FLAC__int64)data[i-28];
749 				case 27: sum += qlp_coeff[26] * (FLAC__int64)data[i-27];
750 				case 26: sum += qlp_coeff[25] * (FLAC__int64)data[i-26];
751 				case 25: sum += qlp_coeff[24] * (FLAC__int64)data[i-25];
752 				case 24: sum += qlp_coeff[23] * (FLAC__int64)data[i-24];
753 				case 23: sum += qlp_coeff[22] * (FLAC__int64)data[i-23];
754 				case 22: sum += qlp_coeff[21] * (FLAC__int64)data[i-22];
755 				case 21: sum += qlp_coeff[20] * (FLAC__int64)data[i-21];
756 				case 20: sum += qlp_coeff[19] * (FLAC__int64)data[i-20];
757 				case 19: sum += qlp_coeff[18] * (FLAC__int64)data[i-19];
758 				case 18: sum += qlp_coeff[17] * (FLAC__int64)data[i-18];
759 				case 17: sum += qlp_coeff[16] * (FLAC__int64)data[i-17];
760 				case 16: sum += qlp_coeff[15] * (FLAC__int64)data[i-16];
761 				case 15: sum += qlp_coeff[14] * (FLAC__int64)data[i-15];
762 				case 14: sum += qlp_coeff[13] * (FLAC__int64)data[i-14];
763 				case 13: sum += qlp_coeff[12] * (FLAC__int64)data[i-13];
764 				         sum += qlp_coeff[11] * (FLAC__int64)data[i-12];
765 				         sum += qlp_coeff[10] * (FLAC__int64)data[i-11];
766 				         sum += qlp_coeff[ 9] * (FLAC__int64)data[i-10];
767 				         sum += qlp_coeff[ 8] * (FLAC__int64)data[i- 9];
768 				         sum += qlp_coeff[ 7] * (FLAC__int64)data[i- 8];
769 				         sum += qlp_coeff[ 6] * (FLAC__int64)data[i- 7];
770 				         sum += qlp_coeff[ 5] * (FLAC__int64)data[i- 6];
771 				         sum += qlp_coeff[ 4] * (FLAC__int64)data[i- 5];
772 				         sum += qlp_coeff[ 3] * (FLAC__int64)data[i- 4];
773 				         sum += qlp_coeff[ 2] * (FLAC__int64)data[i- 3];
774 				         sum += qlp_coeff[ 1] * (FLAC__int64)data[i- 2];
775 				         sum += qlp_coeff[ 0] * (FLAC__int64)data[i- 1];
776 			}
777 			residual[i] = data[i] - (FLAC__int32)(sum >> lp_quantization);
778 		}
779 	}
780 }
781 #endif
782 
783 #endif /* !defined FLAC__INTEGER_ONLY_LIBRARY */
784 
FLAC__lpc_restore_signal(const FLAC__int32 * flac_restrict residual,unsigned data_len,const FLAC__int32 * flac_restrict qlp_coeff,unsigned order,int lp_quantization,FLAC__int32 * flac_restrict data)785 void FLAC__lpc_restore_signal(const FLAC__int32 * flac_restrict residual, unsigned data_len, const FLAC__int32 * flac_restrict qlp_coeff, unsigned order, int lp_quantization, FLAC__int32 * flac_restrict data)
786 #if defined(FLAC__OVERFLOW_DETECT) || !defined(FLAC__LPC_UNROLLED_FILTER_LOOPS)
787 {
788 	FLAC__int64 sumo;
789 	unsigned i, j;
790 	FLAC__int32 sum;
791 	const FLAC__int32 *r = residual, *history;
792 
793 #ifdef FLAC__OVERFLOW_DETECT_VERBOSE
794 	fprintf(stderr,"FLAC__lpc_restore_signal: data_len=%d, order=%u, lpq=%d",data_len,order,lp_quantization);
795 	for(i=0;i<order;i++)
796 		fprintf(stderr,", q[%u]=%d",i,qlp_coeff[i]);
797 	fprintf(stderr,"\n");
798 #endif
799 	FLAC__ASSERT(order > 0);
800 
801 	for(i = 0; i < data_len; i++) {
802 		sumo = 0;
803 		sum = 0;
804 		history = data;
805 		for(j = 0; j < order; j++) {
806 			sum += qlp_coeff[j] * (*(--history));
807 			sumo += (FLAC__int64)qlp_coeff[j] * (FLAC__int64)(*history);
808 			if(sumo > 2147483647ll || sumo < -2147483648ll)
809 				fprintf(stderr,"FLAC__lpc_restore_signal: OVERFLOW, i=%u, j=%u, c=%d, d=%d, sumo=%" PRId64 "\n",i,j,qlp_coeff[j],*history,sumo);
810 		}
811 		*(data++) = *(r++) + (sum >> lp_quantization);
812 	}
813 
814 	/* Here's a slower but clearer version:
815 	for(i = 0; i < data_len; i++) {
816 		sum = 0;
817 		for(j = 0; j < order; j++)
818 			sum += qlp_coeff[j] * data[i-j-1];
819 		data[i] = residual[i] + (sum >> lp_quantization);
820 	}
821 	*/
822 }
823 #else /* fully unrolled version for normal use */
824 {
825 	int i;
826 	FLAC__int32 sum;
827 
828 	FLAC__ASSERT(order > 0);
829 	FLAC__ASSERT(order <= 32);
830 
831 	/*
832 	 * We do unique versions up to 12th order since that's the subset limit.
833 	 * Also they are roughly ordered to match frequency of occurrence to
834 	 * minimize branching.
835 	 */
836 	if(order <= 12) {
837 		if(order > 8) {
838 			if(order > 10) {
839 				if(order == 12) {
840 					for(i = 0; i < (int)data_len; i++) {
841 						sum = 0;
842 						sum += qlp_coeff[11] * data[i-12];
843 						sum += qlp_coeff[10] * data[i-11];
844 						sum += qlp_coeff[9] * data[i-10];
845 						sum += qlp_coeff[8] * data[i-9];
846 						sum += qlp_coeff[7] * data[i-8];
847 						sum += qlp_coeff[6] * data[i-7];
848 						sum += qlp_coeff[5] * data[i-6];
849 						sum += qlp_coeff[4] * data[i-5];
850 						sum += qlp_coeff[3] * data[i-4];
851 						sum += qlp_coeff[2] * data[i-3];
852 						sum += qlp_coeff[1] * data[i-2];
853 						sum += qlp_coeff[0] * data[i-1];
854 						data[i] = residual[i] + (sum >> lp_quantization);
855 					}
856 				}
857 				else { /* order == 11 */
858 					for(i = 0; i < (int)data_len; i++) {
859 						sum = 0;
860 						sum += qlp_coeff[10] * data[i-11];
861 						sum += qlp_coeff[9] * data[i-10];
862 						sum += qlp_coeff[8] * data[i-9];
863 						sum += qlp_coeff[7] * data[i-8];
864 						sum += qlp_coeff[6] * data[i-7];
865 						sum += qlp_coeff[5] * data[i-6];
866 						sum += qlp_coeff[4] * data[i-5];
867 						sum += qlp_coeff[3] * data[i-4];
868 						sum += qlp_coeff[2] * data[i-3];
869 						sum += qlp_coeff[1] * data[i-2];
870 						sum += qlp_coeff[0] * data[i-1];
871 						data[i] = residual[i] + (sum >> lp_quantization);
872 					}
873 				}
874 			}
875 			else {
876 				if(order == 10) {
877 					for(i = 0; i < (int)data_len; i++) {
878 						sum = 0;
879 						sum += qlp_coeff[9] * data[i-10];
880 						sum += qlp_coeff[8] * data[i-9];
881 						sum += qlp_coeff[7] * data[i-8];
882 						sum += qlp_coeff[6] * data[i-7];
883 						sum += qlp_coeff[5] * data[i-6];
884 						sum += qlp_coeff[4] * data[i-5];
885 						sum += qlp_coeff[3] * data[i-4];
886 						sum += qlp_coeff[2] * data[i-3];
887 						sum += qlp_coeff[1] * data[i-2];
888 						sum += qlp_coeff[0] * data[i-1];
889 						data[i] = residual[i] + (sum >> lp_quantization);
890 					}
891 				}
892 				else { /* order == 9 */
893 					for(i = 0; i < (int)data_len; i++) {
894 						sum = 0;
895 						sum += qlp_coeff[8] * data[i-9];
896 						sum += qlp_coeff[7] * data[i-8];
897 						sum += qlp_coeff[6] * data[i-7];
898 						sum += qlp_coeff[5] * data[i-6];
899 						sum += qlp_coeff[4] * data[i-5];
900 						sum += qlp_coeff[3] * data[i-4];
901 						sum += qlp_coeff[2] * data[i-3];
902 						sum += qlp_coeff[1] * data[i-2];
903 						sum += qlp_coeff[0] * data[i-1];
904 						data[i] = residual[i] + (sum >> lp_quantization);
905 					}
906 				}
907 			}
908 		}
909 		else if(order > 4) {
910 			if(order > 6) {
911 				if(order == 8) {
912 					for(i = 0; i < (int)data_len; i++) {
913 						sum = 0;
914 						sum += qlp_coeff[7] * data[i-8];
915 						sum += qlp_coeff[6] * data[i-7];
916 						sum += qlp_coeff[5] * data[i-6];
917 						sum += qlp_coeff[4] * data[i-5];
918 						sum += qlp_coeff[3] * data[i-4];
919 						sum += qlp_coeff[2] * data[i-3];
920 						sum += qlp_coeff[1] * data[i-2];
921 						sum += qlp_coeff[0] * data[i-1];
922 						data[i] = residual[i] + (sum >> lp_quantization);
923 					}
924 				}
925 				else { /* order == 7 */
926 					for(i = 0; i < (int)data_len; i++) {
927 						sum = 0;
928 						sum += qlp_coeff[6] * data[i-7];
929 						sum += qlp_coeff[5] * data[i-6];
930 						sum += qlp_coeff[4] * data[i-5];
931 						sum += qlp_coeff[3] * data[i-4];
932 						sum += qlp_coeff[2] * data[i-3];
933 						sum += qlp_coeff[1] * data[i-2];
934 						sum += qlp_coeff[0] * data[i-1];
935 						data[i] = residual[i] + (sum >> lp_quantization);
936 					}
937 				}
938 			}
939 			else {
940 				if(order == 6) {
941 					for(i = 0; i < (int)data_len; i++) {
942 						sum = 0;
943 						sum += qlp_coeff[5] * data[i-6];
944 						sum += qlp_coeff[4] * data[i-5];
945 						sum += qlp_coeff[3] * data[i-4];
946 						sum += qlp_coeff[2] * data[i-3];
947 						sum += qlp_coeff[1] * data[i-2];
948 						sum += qlp_coeff[0] * data[i-1];
949 						data[i] = residual[i] + (sum >> lp_quantization);
950 					}
951 				}
952 				else { /* order == 5 */
953 					for(i = 0; i < (int)data_len; i++) {
954 						sum = 0;
955 						sum += qlp_coeff[4] * data[i-5];
956 						sum += qlp_coeff[3] * data[i-4];
957 						sum += qlp_coeff[2] * data[i-3];
958 						sum += qlp_coeff[1] * data[i-2];
959 						sum += qlp_coeff[0] * data[i-1];
960 						data[i] = residual[i] + (sum >> lp_quantization);
961 					}
962 				}
963 			}
964 		}
965 		else {
966 			if(order > 2) {
967 				if(order == 4) {
968 					for(i = 0; i < (int)data_len; i++) {
969 						sum = 0;
970 						sum += qlp_coeff[3] * data[i-4];
971 						sum += qlp_coeff[2] * data[i-3];
972 						sum += qlp_coeff[1] * data[i-2];
973 						sum += qlp_coeff[0] * data[i-1];
974 						data[i] = residual[i] + (sum >> lp_quantization);
975 					}
976 				}
977 				else { /* order == 3 */
978 					for(i = 0; i < (int)data_len; i++) {
979 						sum = 0;
980 						sum += qlp_coeff[2] * data[i-3];
981 						sum += qlp_coeff[1] * data[i-2];
982 						sum += qlp_coeff[0] * data[i-1];
983 						data[i] = residual[i] + (sum >> lp_quantization);
984 					}
985 				}
986 			}
987 			else {
988 				if(order == 2) {
989 					for(i = 0; i < (int)data_len; i++) {
990 						sum = 0;
991 						sum += qlp_coeff[1] * data[i-2];
992 						sum += qlp_coeff[0] * data[i-1];
993 						data[i] = residual[i] + (sum >> lp_quantization);
994 					}
995 				}
996 				else { /* order == 1 */
997 					for(i = 0; i < (int)data_len; i++)
998 						data[i] = residual[i] + ((qlp_coeff[0] * data[i-1]) >> lp_quantization);
999 				}
1000 			}
1001 		}
1002 	}
1003 	else { /* order > 12 */
1004 		for(i = 0; i < (int)data_len; i++) {
1005 			sum = 0;
1006 			switch(order) {
1007 				case 32: sum += qlp_coeff[31] * data[i-32];
1008 				case 31: sum += qlp_coeff[30] * data[i-31];
1009 				case 30: sum += qlp_coeff[29] * data[i-30];
1010 				case 29: sum += qlp_coeff[28] * data[i-29];
1011 				case 28: sum += qlp_coeff[27] * data[i-28];
1012 				case 27: sum += qlp_coeff[26] * data[i-27];
1013 				case 26: sum += qlp_coeff[25] * data[i-26];
1014 				case 25: sum += qlp_coeff[24] * data[i-25];
1015 				case 24: sum += qlp_coeff[23] * data[i-24];
1016 				case 23: sum += qlp_coeff[22] * data[i-23];
1017 				case 22: sum += qlp_coeff[21] * data[i-22];
1018 				case 21: sum += qlp_coeff[20] * data[i-21];
1019 				case 20: sum += qlp_coeff[19] * data[i-20];
1020 				case 19: sum += qlp_coeff[18] * data[i-19];
1021 				case 18: sum += qlp_coeff[17] * data[i-18];
1022 				case 17: sum += qlp_coeff[16] * data[i-17];
1023 				case 16: sum += qlp_coeff[15] * data[i-16];
1024 				case 15: sum += qlp_coeff[14] * data[i-15];
1025 				case 14: sum += qlp_coeff[13] * data[i-14];
1026 				case 13: sum += qlp_coeff[12] * data[i-13];
1027 				         sum += qlp_coeff[11] * data[i-12];
1028 				         sum += qlp_coeff[10] * data[i-11];
1029 				         sum += qlp_coeff[ 9] * data[i-10];
1030 				         sum += qlp_coeff[ 8] * data[i- 9];
1031 				         sum += qlp_coeff[ 7] * data[i- 8];
1032 				         sum += qlp_coeff[ 6] * data[i- 7];
1033 				         sum += qlp_coeff[ 5] * data[i- 6];
1034 				         sum += qlp_coeff[ 4] * data[i- 5];
1035 				         sum += qlp_coeff[ 3] * data[i- 4];
1036 				         sum += qlp_coeff[ 2] * data[i- 3];
1037 				         sum += qlp_coeff[ 1] * data[i- 2];
1038 				         sum += qlp_coeff[ 0] * data[i- 1];
1039 			}
1040 			data[i] = residual[i] + (sum >> lp_quantization);
1041 		}
1042 	}
1043 }
1044 #endif
1045 
FLAC__lpc_restore_signal_wide(const FLAC__int32 * flac_restrict residual,unsigned data_len,const FLAC__int32 * flac_restrict qlp_coeff,unsigned order,int lp_quantization,FLAC__int32 * flac_restrict data)1046 void FLAC__lpc_restore_signal_wide(const FLAC__int32 * flac_restrict residual, unsigned data_len, const FLAC__int32 * flac_restrict qlp_coeff, unsigned order, int lp_quantization, FLAC__int32 * flac_restrict data)
1047 #if defined(FLAC__OVERFLOW_DETECT) || !defined(FLAC__LPC_UNROLLED_FILTER_LOOPS)
1048 {
1049 	unsigned i, j;
1050 	FLAC__int64 sum;
1051 	const FLAC__int32 *r = residual, *history;
1052 
1053 #ifdef FLAC__OVERFLOW_DETECT_VERBOSE
1054 	fprintf(stderr,"FLAC__lpc_restore_signal_wide: data_len=%d, order=%u, lpq=%d",data_len,order,lp_quantization);
1055 	for(i=0;i<order;i++)
1056 		fprintf(stderr,", q[%u]=%d",i,qlp_coeff[i]);
1057 	fprintf(stderr,"\n");
1058 #endif
1059 	FLAC__ASSERT(order > 0);
1060 
1061 	for(i = 0; i < data_len; i++) {
1062 		sum = 0;
1063 		history = data;
1064 		for(j = 0; j < order; j++)
1065 			sum += (FLAC__int64)qlp_coeff[j] * (FLAC__int64)(*(--history));
1066 		if(FLAC__bitmath_silog2_wide(sum >> lp_quantization) > 32) {
1067 			fprintf(stderr,"FLAC__lpc_restore_signal_wide: OVERFLOW, i=%u, sum=%" PRId64 "\n", i, (sum >> lp_quantization));
1068 			break;
1069 		}
1070 		if(FLAC__bitmath_silog2_wide((FLAC__int64)(*r) + (sum >> lp_quantization)) > 32) {
1071 			fprintf(stderr,"FLAC__lpc_restore_signal_wide: OVERFLOW, i=%u, residual=%d, sum=%" PRId64 ", data=%" PRId64 "\n", i, *r, (sum >> lp_quantization), ((FLAC__int64)(*r) + (sum >> lp_quantization)));
1072 			break;
1073 		}
1074 		*(data++) = *(r++) + (FLAC__int32)(sum >> lp_quantization);
1075 	}
1076 }
1077 #else /* fully unrolled version for normal use */
1078 {
1079 	int i;
1080 	FLAC__int64 sum;
1081 
1082 	FLAC__ASSERT(order > 0);
1083 	FLAC__ASSERT(order <= 32);
1084 
1085 	/*
1086 	 * We do unique versions up to 12th order since that's the subset limit.
1087 	 * Also they are roughly ordered to match frequency of occurrence to
1088 	 * minimize branching.
1089 	 */
1090 	if(order <= 12) {
1091 		if(order > 8) {
1092 			if(order > 10) {
1093 				if(order == 12) {
1094 					for(i = 0; i < (int)data_len; i++) {
1095 						sum = 0;
1096 						sum += qlp_coeff[11] * (FLAC__int64)data[i-12];
1097 						sum += qlp_coeff[10] * (FLAC__int64)data[i-11];
1098 						sum += qlp_coeff[9] * (FLAC__int64)data[i-10];
1099 						sum += qlp_coeff[8] * (FLAC__int64)data[i-9];
1100 						sum += qlp_coeff[7] * (FLAC__int64)data[i-8];
1101 						sum += qlp_coeff[6] * (FLAC__int64)data[i-7];
1102 						sum += qlp_coeff[5] * (FLAC__int64)data[i-6];
1103 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
1104 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
1105 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
1106 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
1107 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
1108 						data[i] = residual[i] + (FLAC__int32)(sum >> lp_quantization);
1109 					}
1110 				}
1111 				else { /* order == 11 */
1112 					for(i = 0; i < (int)data_len; i++) {
1113 						sum = 0;
1114 						sum += qlp_coeff[10] * (FLAC__int64)data[i-11];
1115 						sum += qlp_coeff[9] * (FLAC__int64)data[i-10];
1116 						sum += qlp_coeff[8] * (FLAC__int64)data[i-9];
1117 						sum += qlp_coeff[7] * (FLAC__int64)data[i-8];
1118 						sum += qlp_coeff[6] * (FLAC__int64)data[i-7];
1119 						sum += qlp_coeff[5] * (FLAC__int64)data[i-6];
1120 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
1121 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
1122 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
1123 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
1124 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
1125 						data[i] = residual[i] + (FLAC__int32)(sum >> lp_quantization);
1126 					}
1127 				}
1128 			}
1129 			else {
1130 				if(order == 10) {
1131 					for(i = 0; i < (int)data_len; i++) {
1132 						sum = 0;
1133 						sum += qlp_coeff[9] * (FLAC__int64)data[i-10];
1134 						sum += qlp_coeff[8] * (FLAC__int64)data[i-9];
1135 						sum += qlp_coeff[7] * (FLAC__int64)data[i-8];
1136 						sum += qlp_coeff[6] * (FLAC__int64)data[i-7];
1137 						sum += qlp_coeff[5] * (FLAC__int64)data[i-6];
1138 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
1139 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
1140 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
1141 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
1142 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
1143 						data[i] = residual[i] + (FLAC__int32)(sum >> lp_quantization);
1144 					}
1145 				}
1146 				else { /* order == 9 */
1147 					for(i = 0; i < (int)data_len; i++) {
1148 						sum = 0;
1149 						sum += qlp_coeff[8] * (FLAC__int64)data[i-9];
1150 						sum += qlp_coeff[7] * (FLAC__int64)data[i-8];
1151 						sum += qlp_coeff[6] * (FLAC__int64)data[i-7];
1152 						sum += qlp_coeff[5] * (FLAC__int64)data[i-6];
1153 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
1154 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
1155 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
1156 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
1157 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
1158 						data[i] = residual[i] + (FLAC__int32)(sum >> lp_quantization);
1159 					}
1160 				}
1161 			}
1162 		}
1163 		else if(order > 4) {
1164 			if(order > 6) {
1165 				if(order == 8) {
1166 					for(i = 0; i < (int)data_len; i++) {
1167 						sum = 0;
1168 						sum += qlp_coeff[7] * (FLAC__int64)data[i-8];
1169 						sum += qlp_coeff[6] * (FLAC__int64)data[i-7];
1170 						sum += qlp_coeff[5] * (FLAC__int64)data[i-6];
1171 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
1172 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
1173 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
1174 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
1175 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
1176 						data[i] = residual[i] + (FLAC__int32)(sum >> lp_quantization);
1177 					}
1178 				}
1179 				else { /* order == 7 */
1180 					for(i = 0; i < (int)data_len; i++) {
1181 						sum = 0;
1182 						sum += qlp_coeff[6] * (FLAC__int64)data[i-7];
1183 						sum += qlp_coeff[5] * (FLAC__int64)data[i-6];
1184 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
1185 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
1186 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
1187 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
1188 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
1189 						data[i] = residual[i] + (FLAC__int32)(sum >> lp_quantization);
1190 					}
1191 				}
1192 			}
1193 			else {
1194 				if(order == 6) {
1195 					for(i = 0; i < (int)data_len; i++) {
1196 						sum = 0;
1197 						sum += qlp_coeff[5] * (FLAC__int64)data[i-6];
1198 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
1199 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
1200 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
1201 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
1202 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
1203 						data[i] = residual[i] + (FLAC__int32)(sum >> lp_quantization);
1204 					}
1205 				}
1206 				else { /* order == 5 */
1207 					for(i = 0; i < (int)data_len; i++) {
1208 						sum = 0;
1209 						sum += qlp_coeff[4] * (FLAC__int64)data[i-5];
1210 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
1211 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
1212 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
1213 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
1214 						data[i] = residual[i] + (FLAC__int32)(sum >> lp_quantization);
1215 					}
1216 				}
1217 			}
1218 		}
1219 		else {
1220 			if(order > 2) {
1221 				if(order == 4) {
1222 					for(i = 0; i < (int)data_len; i++) {
1223 						sum = 0;
1224 						sum += qlp_coeff[3] * (FLAC__int64)data[i-4];
1225 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
1226 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
1227 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
1228 						data[i] = residual[i] + (FLAC__int32)(sum >> lp_quantization);
1229 					}
1230 				}
1231 				else { /* order == 3 */
1232 					for(i = 0; i < (int)data_len; i++) {
1233 						sum = 0;
1234 						sum += qlp_coeff[2] * (FLAC__int64)data[i-3];
1235 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
1236 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
1237 						data[i] = residual[i] + (FLAC__int32)(sum >> lp_quantization);
1238 					}
1239 				}
1240 			}
1241 			else {
1242 				if(order == 2) {
1243 					for(i = 0; i < (int)data_len; i++) {
1244 						sum = 0;
1245 						sum += qlp_coeff[1] * (FLAC__int64)data[i-2];
1246 						sum += qlp_coeff[0] * (FLAC__int64)data[i-1];
1247 						data[i] = residual[i] + (FLAC__int32)(sum >> lp_quantization);
1248 					}
1249 				}
1250 				else { /* order == 1 */
1251 					for(i = 0; i < (int)data_len; i++)
1252 						data[i] = residual[i] + (FLAC__int32)((qlp_coeff[0] * (FLAC__int64)data[i-1]) >> lp_quantization);
1253 				}
1254 			}
1255 		}
1256 	}
1257 	else { /* order > 12 */
1258 		for(i = 0; i < (int)data_len; i++) {
1259 			sum = 0;
1260 			switch(order) {
1261 				case 32: sum += qlp_coeff[31] * (FLAC__int64)data[i-32];
1262 				case 31: sum += qlp_coeff[30] * (FLAC__int64)data[i-31];
1263 				case 30: sum += qlp_coeff[29] * (FLAC__int64)data[i-30];
1264 				case 29: sum += qlp_coeff[28] * (FLAC__int64)data[i-29];
1265 				case 28: sum += qlp_coeff[27] * (FLAC__int64)data[i-28];
1266 				case 27: sum += qlp_coeff[26] * (FLAC__int64)data[i-27];
1267 				case 26: sum += qlp_coeff[25] * (FLAC__int64)data[i-26];
1268 				case 25: sum += qlp_coeff[24] * (FLAC__int64)data[i-25];
1269 				case 24: sum += qlp_coeff[23] * (FLAC__int64)data[i-24];
1270 				case 23: sum += qlp_coeff[22] * (FLAC__int64)data[i-23];
1271 				case 22: sum += qlp_coeff[21] * (FLAC__int64)data[i-22];
1272 				case 21: sum += qlp_coeff[20] * (FLAC__int64)data[i-21];
1273 				case 20: sum += qlp_coeff[19] * (FLAC__int64)data[i-20];
1274 				case 19: sum += qlp_coeff[18] * (FLAC__int64)data[i-19];
1275 				case 18: sum += qlp_coeff[17] * (FLAC__int64)data[i-18];
1276 				case 17: sum += qlp_coeff[16] * (FLAC__int64)data[i-17];
1277 				case 16: sum += qlp_coeff[15] * (FLAC__int64)data[i-16];
1278 				case 15: sum += qlp_coeff[14] * (FLAC__int64)data[i-15];
1279 				case 14: sum += qlp_coeff[13] * (FLAC__int64)data[i-14];
1280 				case 13: sum += qlp_coeff[12] * (FLAC__int64)data[i-13];
1281 				         sum += qlp_coeff[11] * (FLAC__int64)data[i-12];
1282 				         sum += qlp_coeff[10] * (FLAC__int64)data[i-11];
1283 				         sum += qlp_coeff[ 9] * (FLAC__int64)data[i-10];
1284 				         sum += qlp_coeff[ 8] * (FLAC__int64)data[i- 9];
1285 				         sum += qlp_coeff[ 7] * (FLAC__int64)data[i- 8];
1286 				         sum += qlp_coeff[ 6] * (FLAC__int64)data[i- 7];
1287 				         sum += qlp_coeff[ 5] * (FLAC__int64)data[i- 6];
1288 				         sum += qlp_coeff[ 4] * (FLAC__int64)data[i- 5];
1289 				         sum += qlp_coeff[ 3] * (FLAC__int64)data[i- 4];
1290 				         sum += qlp_coeff[ 2] * (FLAC__int64)data[i- 3];
1291 				         sum += qlp_coeff[ 1] * (FLAC__int64)data[i- 2];
1292 				         sum += qlp_coeff[ 0] * (FLAC__int64)data[i- 1];
1293 			}
1294 			data[i] = residual[i] + (FLAC__int32)(sum >> lp_quantization);
1295 		}
1296 	}
1297 }
1298 #endif
1299 
1300 #if defined(_MSC_VER)
1301 #pragma warning ( default : 4028 )
1302 #endif
1303 
1304 #ifndef FLAC__INTEGER_ONLY_LIBRARY
1305 
FLAC__lpc_compute_expected_bits_per_residual_sample(FLAC__double lpc_error,unsigned total_samples)1306 FLAC__double FLAC__lpc_compute_expected_bits_per_residual_sample(FLAC__double lpc_error, unsigned total_samples)
1307 {
1308 	FLAC__double error_scale;
1309 
1310 	FLAC__ASSERT(total_samples > 0);
1311 
1312 	error_scale = 0.5 / (FLAC__double)total_samples;
1313 
1314 	return FLAC__lpc_compute_expected_bits_per_residual_sample_with_error_scale(lpc_error, error_scale);
1315 }
1316 
FLAC__lpc_compute_expected_bits_per_residual_sample_with_error_scale(FLAC__double lpc_error,FLAC__double error_scale)1317 FLAC__double FLAC__lpc_compute_expected_bits_per_residual_sample_with_error_scale(FLAC__double lpc_error, FLAC__double error_scale)
1318 {
1319 	if(lpc_error > 0.0) {
1320 		FLAC__double bps = (FLAC__double)0.5 * log(error_scale * lpc_error) / M_LN2;
1321 		if(bps >= 0.0)
1322 			return bps;
1323 		else
1324 			return 0.0;
1325 	}
1326 	else if(lpc_error < 0.0) { /* error should not be negative but can happen due to inadequate floating-point resolution */
1327 		return 1e32;
1328 	}
1329 	else {
1330 		return 0.0;
1331 	}
1332 }
1333 
FLAC__lpc_compute_best_order(const FLAC__double lpc_error[],unsigned max_order,unsigned total_samples,unsigned overhead_bits_per_order)1334 unsigned FLAC__lpc_compute_best_order(const FLAC__double lpc_error[], unsigned max_order, unsigned total_samples, unsigned overhead_bits_per_order)
1335 {
1336 	unsigned order, indx, best_index; /* 'index' the index into lpc_error; index==order-1 since lpc_error[0] is for order==1, lpc_error[1] is for order==2, etc */
1337 	FLAC__double bits, best_bits, error_scale;
1338 
1339 	FLAC__ASSERT(max_order > 0);
1340 	FLAC__ASSERT(total_samples > 0);
1341 
1342 	error_scale = 0.5 / (FLAC__double)total_samples;
1343 
1344 	best_index = 0;
1345 	best_bits = (unsigned)(-1);
1346 
1347 	for(indx = 0, order = 1; indx < max_order; indx++, order++) {
1348 		bits = FLAC__lpc_compute_expected_bits_per_residual_sample_with_error_scale(lpc_error[indx], error_scale) * (FLAC__double)(total_samples - order) + (FLAC__double)(order * overhead_bits_per_order);
1349 		if(bits < best_bits) {
1350 			best_index = indx;
1351 			best_bits = bits;
1352 		}
1353 	}
1354 
1355 	return best_index+1; /* +1 since indx of lpc_error[] is order-1 */
1356 }
1357 
1358 #endif /* !defined FLAC__INTEGER_ONLY_LIBRARY */
1359