/src/pjsip/third_party/ilbc/iCBSearch.c

Source

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

       iLBC Speech Coder ANSI-C Source Code

       iCBSearch.c

       Copyright (C) The Internet Society (2004).
       All Rights Reserved.

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

   #include <math.h>
   #include <string.h>

   #include "iLBC_define.h"
   #include "gainquant.h"
   #include "createCB.h"
   #include "filter.h"
   #include "constants.h"

   /*----------------------------------------------------------------*
    *  Search routine for codebook encoding and gain quantization.
    *---------------------------------------------------------------*/

   void iCBSearch(
       iLBC_Enc_Inst_t *iLBCenc_inst,
                           /* (i) the encoder state structure */
       int *index,         /* (o) Codebook indices */
       int *gain_index,/* (o) Gain quantization indices */





       float *intarget,/* (i) Target vector for encoding */
       float *mem,         /* (i) Buffer for codebook construction */
       int lMem,           /* (i) Length of buffer */
       int lTarget,    /* (i) Length of vector */
       int nStages,    /* (i) Number of codebook stages */
       float *weightDenum, /* (i) weighting filter coefficients */
       float *weightState, /* (i) weighting filter state */
       int block           /* (i) the sub-block number */
   ){
       int i, j, icount, stage, best_index, range, counter;
       float max_measure, gain, measure, crossDot, ftmp;
       float gains[CB_NSTAGES];
       float target[SUBL];
       int base_index, sInd, eInd, base_size;
       int sIndAug=0, eIndAug=0;
       float buf[CB_MEML+SUBL+2*LPC_FILTERORDER];
       float invenergy[CB_EXPAND*128], energy[CB_EXPAND*128];
       float *pp, *ppi=0, *ppo=0, *ppe=0;
       float cbvectors[CB_MEML];
       float tene, cene, cvec[SUBL];
       float aug_vec[SUBL];

       memset(cvec,0,SUBL*sizeof(float));

       /* Determine size of codebook sections */

       base_size=lMem-lTarget+1;

       if (lTarget==SUBL) {
           base_size=lMem-lTarget+1+lTarget/2;
       }

       /* setup buffer for weighting */

       memcpy(buf,weightState,sizeof(float)*LPC_FILTERORDER);
       memcpy(buf+LPC_FILTERORDER,mem,lMem*sizeof(float));
       memcpy(buf+LPC_FILTERORDER+lMem,intarget,lTarget*sizeof(float));

       /* weighting */

       AllPoleFilter(buf+LPC_FILTERORDER, weightDenum,
           lMem+lTarget, LPC_FILTERORDER);

       /* Construct the codebook and target needed */

       memcpy(target, buf+LPC_FILTERORDER+lMem, lTarget*sizeof(float));

       tene=0.0;





       for (i=0; i<lTarget; i++) {
           tene+=target[i]*target[i];
       }

       /* Prepare search over one more codebook section. This section
          is created by filtering the original buffer with a filter. */

       filteredCBvecs(cbvectors, buf+LPC_FILTERORDER, lMem);

       /* The Main Loop over stages */

       for (stage=0; stage<nStages; stage++) {

           range = search_rangeTbl[block][stage];

           /* initialize search measure */

           max_measure = (float)-10000000.0;
           gain = (float)0.0;
           best_index = 0;

           /* Compute cross dot product between the target
              and the CB memory */

           crossDot=0.0;
           pp=buf+LPC_FILTERORDER+lMem-lTarget;
           for (j=0; j<lTarget; j++) {
               crossDot += target[j]*(*pp++);
           }

           if (stage==0) {

               /* Calculate energy in the first block of
                 'lTarget' samples. */
               ppe = energy;
               ppi = buf+LPC_FILTERORDER+lMem-lTarget-1;
               ppo = buf+LPC_FILTERORDER+lMem-1;

               *ppe=0.0;
               pp=buf+LPC_FILTERORDER+lMem-lTarget;
               for (j=0; j<lTarget; j++) {
                   *ppe+=(*pp)*(*pp);
       ++pp;
               }

               if (*ppe>0.0) {
                   invenergy[0] = (float) 1.0 / (*ppe + EPS);
               } else {
                   invenergy[0] = (float) 0.0;





               }
               ppe++;

               measure=(float)-10000000.0;

               if (crossDot > 0.0) {
                      measure = crossDot*crossDot*invenergy[0];
               }
           }
           else {
               measure = crossDot*crossDot*invenergy[0];
           }

           /* check if measure is better */
           ftmp = crossDot*invenergy[0];

           if ((measure>max_measure) && (fabs(ftmp)<CB_MAXGAIN)) {
               best_index = 0;
               max_measure = measure;
               gain = ftmp;
           }

           /* loop over the main first codebook section,
              full search */

           for (icount=1; icount<range; icount++) {

               /* calculate measure */

               crossDot=0.0;
               pp = buf+LPC_FILTERORDER+lMem-lTarget-icount;

               for (j=0; j<lTarget; j++) {
                   crossDot += target[j]*(*pp++);
               }

               if (stage==0) {
                   *ppe++ = energy[icount-1] + (*ppi)*(*ppi) -
                       (*ppo)*(*ppo);
                   ppo--;
                   ppi--;

                   if (energy[icount]>0.0) {
                       invenergy[icount] =
                           (float)1.0/(energy[icount]+EPS);
                   } else {
                       invenergy[icount] = (float) 0.0;
                   }





                   measure=(float)-10000000.0;

                   if (crossDot > 0.0) {
                       measure = crossDot*crossDot*invenergy[icount];
                   }
               }
               else {
                   measure = crossDot*crossDot*invenergy[icount];
               }

               /* check if measure is better */
               ftmp = crossDot*invenergy[icount];

               if ((measure>max_measure) && (fabs(ftmp)<CB_MAXGAIN)) {
                   best_index = icount;
                   max_measure = measure;
                   gain = ftmp;
               }
           }

           /* Loop over augmented part in the first codebook
            * section, full search.
            * The vectors are interpolated.
            */

           if (lTarget==SUBL) {

               /* Search for best possible cb vector and
                  compute the CB-vectors' energy. */
               searchAugmentedCB(20, 39, stage, base_size-lTarget/2,
                   target, buf+LPC_FILTERORDER+lMem,
                   &max_measure, &best_index, &gain, energy,
                   invenergy);
           }

           /* set search range for following codebook sections */

           base_index=best_index;

           /* unrestricted search */

#    if CB_RESRANGE == -1
           //if (CB_RESRANGE == -1) {
               sInd=0;
               eInd=range-1;
               sIndAug=20;
               eIndAug=39;
           //}

#    else

           /* restricted search around best index from first
           codebook section */

           //else {
               /* Initialize search indices */
               sIndAug=0;
               eIndAug=0;
               sInd=base_index-CB_RESRANGE/2;
               eInd=sInd+CB_RESRANGE;

               if (lTarget==SUBL) {

                   if (sInd<0) {

                       sIndAug = 40 + sInd;
                       eIndAug = 39;
                       sInd=0;

                   } else if ( base_index < (base_size-20) ) {

                       if (eInd > range) {
                           sInd -= (eInd-range);
                           eInd = range;
                       }
                   } else { /* base_index >= (base_size-20) */

                       if (sInd < (base_size-20)) {
                           sIndAug = 20;
                           sInd = 0;
                           eInd = 0;
                           eIndAug = 19 + CB_RESRANGE;

                           if(eIndAug > 39) {
                               eInd = eIndAug-39;
                               eIndAug = 39;
                           }
                       } else {
                           sIndAug = 20 + sInd - (base_size-20);
                           eIndAug = 39;
                           sInd = 0;
                           eInd = CB_RESRANGE - (eIndAug-sIndAug+1);
                       }
                   }

               } else { /* lTarget = 22 or 23 */

                   if (sInd < 0) {
                       eInd -= sInd;





                       sInd = 0;
                   }

                   if(eInd > range) {
                       sInd -= (eInd - range);
                       eInd = range;
                   }
               }

           //}
#    endif /* CB_RESRANGE == -1 */


           /* search of higher codebook section */

           /* index search range */
           counter = sInd;
           sInd += base_size;
           eInd += base_size;


           if (stage==0) {
               ppe = energy+base_size;
               *ppe=0.0;

               pp=cbvectors+lMem-lTarget;
               for (j=0; j<lTarget; j++) {
                   *ppe+=(*pp)*(*pp);
       ++pp;
               }

               ppi = cbvectors + lMem - 1 - lTarget;
               ppo = cbvectors + lMem - 1;

               for (j=0; j<(range-1); j++) {
                   *(ppe+1) = *ppe + (*ppi)*(*ppi) - (*ppo)*(*ppo);
                   ppo--;
                   ppi--;
                   ppe++;
               }
           }

           /* loop over search range */

           for (icount=sInd; icount<eInd; icount++) {

               /* calculate measure */

               crossDot=0.0;
               pp=cbvectors + lMem - (counter++) - lTarget;

               for (j=0;j<lTarget;j++) {





                   crossDot += target[j]*(*pp++);
               }

               if (energy[icount]>0.0) {
                   invenergy[icount] =(float)1.0/(energy[icount]+EPS);
               } else {
                   invenergy[icount] =(float)0.0;
               }

               if (stage==0) {

                   measure=(float)-10000000.0;

                   if (crossDot > 0.0) {
                       measure = crossDot*crossDot*
                           invenergy[icount];
                   }
               }
               else {
                   measure = crossDot*crossDot*invenergy[icount];
               }

               /* check if measure is better */
               ftmp = crossDot*invenergy[icount];

               if ((measure>max_measure) && (fabs(ftmp)<CB_MAXGAIN)) {
                   best_index = icount;
                   max_measure = measure;
                   gain = ftmp;
               }
           }

           /* Search the augmented CB inside the limited range. */

           if ((lTarget==SUBL)&&(sIndAug!=0)) {
               searchAugmentedCB(sIndAug, eIndAug, stage,
                   2*base_size-20, target, cbvectors+lMem,
                   &max_measure, &best_index, &gain, energy,
                   invenergy);
           }

           /* record best index */

           index[stage] = best_index;

           /* gain quantization */

           if (stage==0){






               if (gain<0.0){
                   gain = 0.0;
               }

               if (gain>CB_MAXGAIN) {
                   gain = (float)CB_MAXGAIN;
               }
               gain = gainquant(gain, 1.0, 32, &gain_index[stage]);
           }
           else {
               if (stage==1) {
                   gain = gainquant(gain, (float)fabs(gains[stage-1]),
                       16, &gain_index[stage]);
               } else {
                   gain = gainquant(gain, (float)fabs(gains[stage-1]),
                       8, &gain_index[stage]);
               }
           }

           /* Extract the best (according to measure)
              codebook vector */

           if (lTarget==(STATE_LEN-iLBCenc_inst->state_short_len)) {

               if (index[stage]<base_size) {
                   pp=buf+LPC_FILTERORDER+lMem-lTarget-index[stage];
               } else {
                   pp=cbvectors+lMem-lTarget-
                       index[stage]+base_size;
               }
           } else {

               if (index[stage]<base_size) {
                   if (index[stage]<(base_size-20)) {
                       pp=buf+LPC_FILTERORDER+lMem-
                           lTarget-index[stage];
                   } else {
                       createAugmentedVec(index[stage]-base_size+40,
                               buf+LPC_FILTERORDER+lMem,aug_vec);
                       pp=aug_vec;
                   }
               } else {
                   int filterno, position;

                   filterno=index[stage]/base_size;
                   position=index[stage]-filterno*base_size;







                   if (position<(base_size-20)) {
                       pp=cbvectors+filterno*lMem-lTarget-
                           index[stage]+filterno*base_size;
                   } else {
                       createAugmentedVec(
                           index[stage]-(filterno+1)*base_size+40,
                           cbvectors+filterno*lMem,aug_vec);
                       pp=aug_vec;
                   }
               }
           }

           /* Subtract the best codebook vector, according
              to measure, from the target vector */

           for (j=0;j<lTarget;j++) {
               cvec[j] += gain*(*pp);
               target[j] -= gain*(*pp++);
           }

           /* record quantized gain */

           gains[stage]=gain;

       }/* end of Main Loop. for (stage=0;... */

       /* Gain adjustment for energy matching */
       cene=0.0;
       for (i=0; i<lTarget; i++) {
           cene+=cvec[i]*cvec[i];
       }
       j=gain_index[0];

       for (i=gain_index[0]; i<32; i++) {
           ftmp=cene*gain_sq5Tbl[i]*gain_sq5Tbl[i];

           if ((ftmp<(tene*gains[0]*gains[0])) &&
               (gain_sq5Tbl[j]<(2.0*gains[0]))) {
               j=i;
           }
       }
       gain_index[0]=j;
   }










Coverage Report

Created: 2026-03-12 06:59

Line	Count	Source
1
2		/******************************************************************
3
4		iLBC Speech Coder ANSI-C Source Code
5
6		iCBSearch.c
7
8		Copyright (C) The Internet Society (2004).
9		All Rights Reserved.
10
11		******************************************************************/
12
13		#include <math.h>
14		#include <string.h>
15
16		#include "iLBC_define.h"
17		#include "gainquant.h"
18		#include "createCB.h"
19		#include "filter.h"
20		#include "constants.h"
21
22		/----------------------------------------------------------------
23		* Search routine for codebook encoding and gain quantization.
24		---------------------------------------------------------------/
25
26		void iCBSearch(
27		iLBC_Enc_Inst_t *iLBCenc_inst,
28		/* (i) the encoder state structure */
29		int index, / (o) Codebook indices */
30		int gain_index,/ (o) Gain quantization indices */
31
32
33
34
35
36		float intarget,/ (i) Target vector for encoding */
37		float mem, / (i) Buffer for codebook construction */
38		int lMem, /* (i) Length of buffer */
39		int lTarget, /* (i) Length of vector */
40		int nStages, /* (i) Number of codebook stages */
41		float weightDenum, / (i) weighting filter coefficients */
42		float weightState, / (i) weighting filter state */
43		int block /* (i) the sub-block number */
44	0	){
45	0	int i, j, icount, stage, best_index, range, counter;
46	0	float max_measure, gain, measure, crossDot, ftmp;
47	0	float gains[CB_NSTAGES];
48	0	float target[SUBL];
49	0	int base_index, sInd, eInd, base_size;
50	0	int sIndAug=0, eIndAug=0;
51	0	float buf[CB_MEML+SUBL+2*LPC_FILTERORDER];
52	0	float invenergy[CB_EXPAND128], energy[CB_EXPAND128];
53	0	float pp, ppi=0, ppo=0, ppe=0;
54	0	float cbvectors[CB_MEML];
55	0	float tene, cene, cvec[SUBL];
56	0	float aug_vec[SUBL];
57
58	0	memset(cvec,0,SUBL*sizeof(float));
59
60		/* Determine size of codebook sections */
61
62	0	base_size=lMem-lTarget+1;
63
64	0	if (lTarget==SUBL) {
65	0	base_size=lMem-lTarget+1+lTarget/2;
66	0	}
67
68		/* setup buffer for weighting */
69
70	0	memcpy(buf,weightState,sizeof(float)*LPC_FILTERORDER);
71	0	memcpy(buf+LPC_FILTERORDER,mem,lMem*sizeof(float));
72	0	memcpy(buf+LPC_FILTERORDER+lMem,intarget,lTarget*sizeof(float));
73
74		/* weighting */
75
76	0	AllPoleFilter(buf+LPC_FILTERORDER, weightDenum,
77	0	lMem+lTarget, LPC_FILTERORDER);
78
79		/* Construct the codebook and target needed */
80
81	0	memcpy(target, buf+LPC_FILTERORDER+lMem, lTarget*sizeof(float));
82
83	0	tene=0.0;
84
85
86
87
88
89	0	for (i=0; i<lTarget; i++) {
90	0	tene+=target[i]*target[i];
91	0	}
92
93		/* Prepare search over one more codebook section. This section
94		is created by filtering the original buffer with a filter. */
95
96	0	filteredCBvecs(cbvectors, buf+LPC_FILTERORDER, lMem);
97
98		/* The Main Loop over stages */
99
100	0	for (stage=0; stage<nStages; stage++) {
101
102	0	range = search_rangeTbl[block][stage];
103
104		/* initialize search measure */
105
106	0	max_measure = (float)-10000000.0;
107	0	gain = (float)0.0;
108	0	best_index = 0;
109
110		/* Compute cross dot product between the target
111		and the CB memory */
112
113	0	crossDot=0.0;
114	0	pp=buf+LPC_FILTERORDER+lMem-lTarget;
115	0	for (j=0; j<lTarget; j++) {
116	0	crossDot += target[j](pp++);
117	0	}
118
119	0	if (stage==0) {
120
121		/* Calculate energy in the first block of
122		'lTarget' samples. */
123	0	ppe = energy;
124	0	ppi = buf+LPC_FILTERORDER+lMem-lTarget-1;
125	0	ppo = buf+LPC_FILTERORDER+lMem-1;
126
127	0	*ppe=0.0;
128	0	pp=buf+LPC_FILTERORDER+lMem-lTarget;
129	0	for (j=0; j<lTarget; j++) {
130	0	ppe+=(pp)(pp);
131	0	++pp;
132	0	}
133
134	0	if (*ppe>0.0) {
135	0	invenergy[0] = (float) 1.0 / (*ppe + EPS);
136	0	} else {
137	0	invenergy[0] = (float) 0.0;
138
139
140
141
142
143	0	}
144	0	ppe++;
145
146	0	measure=(float)-10000000.0;
147
148	0	if (crossDot > 0.0) {
149	0	measure = crossDotcrossDotinvenergy[0];
150	0	}
151	0	}
152	0	else {
153	0	measure = crossDotcrossDotinvenergy[0];
154	0	}
155
156		/* check if measure is better */
157	0	ftmp = crossDot*invenergy[0];
158
159	0	if ((measure>max_measure) && (fabs(ftmp)<CB_MAXGAIN)) {
160	0	best_index = 0;
161	0	max_measure = measure;
162	0	gain = ftmp;
163	0	}
164
165		/* loop over the main first codebook section,
166		full search */
167
168	0	for (icount=1; icount<range; icount++) {
169
170		/* calculate measure */
171
172	0	crossDot=0.0;
173	0	pp = buf+LPC_FILTERORDER+lMem-lTarget-icount;
174
175	0	for (j=0; j<lTarget; j++) {
176	0	crossDot += target[j](pp++);
177	0	}
178
179	0	if (stage==0) {
180	0	ppe++ = energy[icount-1] + (ppi)(ppi) -
181	0	(ppo)(*ppo);
182	0	ppo--;
183	0	ppi--;
184
185	0	if (energy[icount]>0.0) {
186	0	invenergy[icount] =
187	0	(float)1.0/(energy[icount]+EPS);
188	0	} else {
189	0	invenergy[icount] = (float) 0.0;
190	0	}
191
192
193
194
195
196	0	measure=(float)-10000000.0;
197
198	0	if (crossDot > 0.0) {
199	0	measure = crossDotcrossDotinvenergy[icount];
200	0	}
201	0	}
202	0	else {
203	0	measure = crossDotcrossDotinvenergy[icount];
204	0	}
205
206		/* check if measure is better */
207	0	ftmp = crossDot*invenergy[icount];
208
209	0	if ((measure>max_measure) && (fabs(ftmp)<CB_MAXGAIN)) {
210	0	best_index = icount;
211	0	max_measure = measure;
212	0	gain = ftmp;
213	0	}
214	0	}
215
216		/* Loop over augmented part in the first codebook
217		* section, full search.
218		* The vectors are interpolated.
219		*/
220
221	0	if (lTarget==SUBL) {
222
223		/* Search for best possible cb vector and
224		compute the CB-vectors' energy. */
225	0	searchAugmentedCB(20, 39, stage, base_size-lTarget/2,
226	0	target, buf+LPC_FILTERORDER+lMem,
227	0	&max_measure, &best_index, &gain, energy,
228	0	invenergy);
229	0	}
230
231		/* set search range for following codebook sections */
232
233	0	base_index=best_index;
234
235		/* unrestricted search */
236
237		# if CB_RESRANGE == -1
238		//if (CB_RESRANGE == -1) {
239		sInd=0;
240		eInd=range-1;
241		sIndAug=20;
242		eIndAug=39;
243		//}
244
245		# else
246
247		/* restricted search around best index from first
248		codebook section */
249
250		//else {
251		/* Initialize search indices */
252	0	sIndAug=0;
253	0	eIndAug=0;
254	0	sInd=base_index-CB_RESRANGE/2;
255	0	eInd=sInd+CB_RESRANGE;
256
257	0	if (lTarget==SUBL) {
258
259	0	if (sInd<0) {
260
261	0	sIndAug = 40 + sInd;
262	0	eIndAug = 39;
263	0	sInd=0;
264
265	0	} else if ( base_index < (base_size-20) ) {
266
267	0	if (eInd > range) {
268	0	sInd -= (eInd-range);
269	0	eInd = range;
270	0	}
271	0	} else { /* base_index >= (base_size-20) */
272
273	0	if (sInd < (base_size-20)) {
274	0	sIndAug = 20;
275	0	sInd = 0;
276	0	eInd = 0;
277	0	eIndAug = 19 + CB_RESRANGE;
278
279	0	if(eIndAug > 39) {
280	0	eInd = eIndAug-39;
281	0	eIndAug = 39;
282	0	}
283	0	} else {
284	0	sIndAug = 20 + sInd - (base_size-20);
285	0	eIndAug = 39;
286	0	sInd = 0;
287	0	eInd = CB_RESRANGE - (eIndAug-sIndAug+1);
288	0	}
289	0	}
290
291	0	} else { /* lTarget = 22 or 23 */
292
293	0	if (sInd < 0) {
294	0	eInd -= sInd;
295
296
297
298
299
300	0	sInd = 0;
301	0	}
302
303	0	if(eInd > range) {
304	0	sInd -= (eInd - range);
305	0	eInd = range;
306	0	}
307	0	}
308
309		//}
310	0	# endif /* CB_RESRANGE == -1 */
311
312
313		/* search of higher codebook section */
314
315		/* index search range */
316	0	counter = sInd;
317	0	sInd += base_size;
318	0	eInd += base_size;
319
320
321	0	if (stage==0) {
322	0	ppe = energy+base_size;
323	0	*ppe=0.0;
324
325	0	pp=cbvectors+lMem-lTarget;
326	0	for (j=0; j<lTarget; j++) {
327	0	ppe+=(pp)(pp);
328	0	++pp;
329	0	}
330
331	0	ppi = cbvectors + lMem - 1 - lTarget;
332	0	ppo = cbvectors + lMem - 1;
333
334	0	for (j=0; j<(range-1); j++) {
335	0	(ppe+1) = ppe + (ppi)(ppi) - (ppo)(ppo);
336	0	ppo--;
337	0	ppi--;
338	0	ppe++;
339	0	}
340	0	}
341
342		/* loop over search range */
343
344	0	for (icount=sInd; icount<eInd; icount++) {
345
346		/* calculate measure */
347
348	0	crossDot=0.0;
349	0	pp=cbvectors + lMem - (counter++) - lTarget;
350
351	0	for (j=0;j<lTarget;j++) {
352
353
354
355
356
357	0	crossDot += target[j](pp++);
358	0	}
359
360	0	if (energy[icount]>0.0) {
361	0	invenergy[icount] =(float)1.0/(energy[icount]+EPS);
362	0	} else {
363	0	invenergy[icount] =(float)0.0;
364	0	}
365
366	0	if (stage==0) {
367
368	0	measure=(float)-10000000.0;
369
370	0	if (crossDot > 0.0) {
371	0	measure = crossDotcrossDot
372	0	invenergy[icount];
373	0	}
374	0	}
375	0	else {
376	0	measure = crossDotcrossDotinvenergy[icount];
377	0	}
378
379		/* check if measure is better */
380	0	ftmp = crossDot*invenergy[icount];
381
382	0	if ((measure>max_measure) && (fabs(ftmp)<CB_MAXGAIN)) {
383	0	best_index = icount;
384	0	max_measure = measure;
385	0	gain = ftmp;
386	0	}
387	0	}
388
389		/* Search the augmented CB inside the limited range. */
390
391	0	if ((lTarget==SUBL)&&(sIndAug!=0)) {
392	0	searchAugmentedCB(sIndAug, eIndAug, stage,
393	0	2*base_size-20, target, cbvectors+lMem,
394	0	&max_measure, &best_index, &gain, energy,
395	0	invenergy);
396	0	}
397
398		/* record best index */
399
400	0	index[stage] = best_index;
401
402		/* gain quantization */
403
404	0	if (stage==0){
405
406
407
408
409
410
411	0	if (gain<0.0){
412	0	gain = 0.0;
413	0	}
414
415	0	if (gain>CB_MAXGAIN) {
416	0	gain = (float)CB_MAXGAIN;
417	0	}
418	0	gain = gainquant(gain, 1.0, 32, &gain_index[stage]);
419	0	}
420	0	else {
421	0	if (stage==1) {
422	0	gain = gainquant(gain, (float)fabs(gains[stage-1]),
423	0	16, &gain_index[stage]);
424	0	} else {
425	0	gain = gainquant(gain, (float)fabs(gains[stage-1]),
426	0	8, &gain_index[stage]);
427	0	}
428	0	}
429
430		/* Extract the best (according to measure)
431		codebook vector */
432
433	0	if (lTarget==(STATE_LEN-iLBCenc_inst->state_short_len)) {
434
435	0	if (index[stage]<base_size) {
436	0	pp=buf+LPC_FILTERORDER+lMem-lTarget-index[stage];
437	0	} else {
438	0	pp=cbvectors+lMem-lTarget-
439	0	index[stage]+base_size;
440	0	}
441	0	} else {
442
443	0	if (index[stage]<base_size) {
444	0	if (index[stage]<(base_size-20)) {
445	0	pp=buf+LPC_FILTERORDER+lMem-
446	0	lTarget-index[stage];
447	0	} else {
448	0	createAugmentedVec(index[stage]-base_size+40,
449	0	buf+LPC_FILTERORDER+lMem,aug_vec);
450	0	pp=aug_vec;
451	0	}
452	0	} else {
453	0	int filterno, position;
454
455	0	filterno=index[stage]/base_size;
456	0	position=index[stage]-filterno*base_size;
457
458
459
460
461
462
463
464	0	if (position<(base_size-20)) {
465	0	pp=cbvectors+filterno*lMem-lTarget-
466	0	index[stage]+filterno*base_size;
467	0	} else {
468	0	createAugmentedVec(
469	0	index[stage]-(filterno+1)*base_size+40,
470	0	cbvectors+filterno*lMem,aug_vec);
471	0	pp=aug_vec;
472	0	}
473	0	}
474	0	}
475
476		/* Subtract the best codebook vector, according
477		to measure, from the target vector */
478
479	0	for (j=0;j<lTarget;j++) {
480	0	cvec[j] += gain(pp);
481	0	target[j] -= gain(pp++);
482	0	}
483
484		/* record quantized gain */
485
486	0	gains[stage]=gain;
487
488	0	}/* end of Main Loop. for (stage=0;... */
489
490		/* Gain adjustment for energy matching */
491	0	cene=0.0;
492	0	for (i=0; i<lTarget; i++) {
493	0	cene+=cvec[i]*cvec[i];
494	0	}
495	0	j=gain_index[0];
496
497	0	for (i=gain_index[0]; i<32; i++) {
498	0	ftmp=cenegain_sq5Tbl[i]gain_sq5Tbl[i];
499
500	0	if ((ftmp<(tenegains[0]gains[0])) &&
501	0	(gain_sq5Tbl[j]<(2.0*gains[0]))) {
502	0	j=i;
503	0	}
504	0	}
505	0	gain_index[0]=j;
506	0	}
507
508
509
510
511
512
513
514
515