1
2 /* -----------------------------------------------------------------------------------------------------------
3 Software License for The Fraunhofer FDK AAC Codec Library for Android
4
5 � Copyright 1995 - 2013 Fraunhofer-Gesellschaft zur F�rderung der angewandten Forschung e.V.
6 All rights reserved.
7
8 1. INTRODUCTION
9 The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements
10 the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
11 This FDK AAC Codec software is intended to be used on a wide variety of Android devices.
12
13 AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual
14 audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by
15 independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part
16 of the MPEG specifications.
17
18 Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
19 may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners
20 individually for the purpose of encoding or decoding bit streams in products that are compliant with
21 the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license
22 these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec
23 software may already be covered under those patent licenses when it is used for those licensed purposes only.
24
25 Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
26 are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional
27 applications information and documentation.
28
29 2. COPYRIGHT LICENSE
30
31 Redistribution and use in source and binary forms, with or without modification, are permitted without
32 payment of copyright license fees provided that you satisfy the following conditions:
33
34 You must retain the complete text of this software license in redistributions of the FDK AAC Codec or
35 your modifications thereto in source code form.
36
37 You must retain the complete text of this software license in the documentation and/or other materials
38 provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form.
39 You must make available free of charge copies of the complete source code of the FDK AAC Codec and your
40 modifications thereto to recipients of copies in binary form.
41
42 The name of Fraunhofer may not be used to endorse or promote products derived from this library without
43 prior written permission.
44
45 You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec
46 software or your modifications thereto.
47
48 Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software
49 and the date of any change. For modified versions of the FDK AAC Codec, the term
50 "Fraunhofer FDK AAC Codec Library for Android" must be replaced by the term
51 "Third-Party Modified Version of the Fraunhofer FDK AAC Codec Library for Android."
52
53 3. NO PATENT LICENSE
54
55 NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer,
56 ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with
57 respect to this software.
58
59 You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized
60 by appropriate patent licenses.
61
62 4. DISCLAIMER
63
64 This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright holders and contributors
65 "AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, including but not limited to the implied warranties
66 of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
67 CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages,
68 including but not limited to procurement of substitute goods or services; loss of use, data, or profits,
69 or business interruption, however caused and on any theory of liability, whether in contract, strict
70 liability, or tort (including negligence), arising in any way out of the use of this software, even if
71 advised of the possibility of such damage.
72
73 5. CONTACT INFORMATION
74
75 Fraunhofer Institute for Integrated Circuits IIS
76 Attention: Audio and Multimedia Departments - FDK AAC LL
77 Am Wolfsmantel 33
78 91058 Erlangen, Germany
79
80 www.iis.fraunhofer.de/amm
81 amm-info@iis.fraunhofer.de
82 ----------------------------------------------------------------------------------------------------------- */
83
84 /*!
85 \file
86 \brief frequency scale
87 \author Tobias Chalupka
88 */
89
90 #include "sbrenc_freq_sca.h"
91 #include "sbr_misc.h"
92
93 #include "genericStds.h"
94
95 /* StartFreq */
96 static INT getStartFreq(INT fsCore, const INT start_freq);
97
98 /* StopFreq */
99 static INT getStopFreq(INT fsCore, const INT stop_freq);
100
101 static INT numberOfBands(INT b_p_o, INT start, INT stop, FIXP_DBL warp_factor);
102 static void CalcBands(INT * diff, INT start , INT stop , INT num_bands);
103 static INT modifyBands(INT max_band, INT * diff, INT length);
104 static void cumSum(INT start_value, INT* diff, INT length, UCHAR *start_adress);
105
106
107
108 /*******************************************************************************
109 Functionname: FDKsbrEnc_getSbrStartFreqRAW
110 *******************************************************************************
111 Description:
112
113 Arguments:
114
115 Return:
116 *******************************************************************************/
117
118 INT
FDKsbrEnc_getSbrStartFreqRAW(INT startFreq,INT fsCore)119 FDKsbrEnc_getSbrStartFreqRAW (INT startFreq, INT fsCore)
120 {
121 INT result;
122
123 if ( startFreq < 0 || startFreq > 15) {
124 return -1;
125 }
126 /* Update startFreq struct */
127 result = getStartFreq(fsCore, startFreq);
128
129 result = (result*(fsCore>>5)+1)>>1; /* (result*fsSBR/QMFbands+1)>>1; */
130
131 return (result);
132
133 } /* End FDKsbrEnc_getSbrStartFreqRAW */
134
135
136 /*******************************************************************************
137 Functionname: getSbrStopFreq
138 *******************************************************************************
139 Description:
140
141 Arguments:
142
143 Return:
144 *******************************************************************************/
FDKsbrEnc_getSbrStopFreqRAW(INT stopFreq,INT fsCore)145 INT FDKsbrEnc_getSbrStopFreqRAW (INT stopFreq, INT fsCore)
146 {
147 INT result;
148
149 if ( stopFreq < 0 || stopFreq > 13)
150 return -1;
151
152 /* Uppdate stopFreq struct */
153 result = getStopFreq(fsCore, stopFreq);
154 result = (result*(fsCore>>5)+1)>>1; /* (result*fsSBR/QMFbands+1)>>1; */
155
156 return (result);
157 } /* End getSbrStopFreq */
158
159
160 /*******************************************************************************
161 Functionname: getStartFreq
162 *******************************************************************************
163 Description:
164
165 Arguments: fsCore - core sampling rate
166
167
168 Return:
169 *******************************************************************************/
170 static INT
getStartFreq(INT fsCore,const INT start_freq)171 getStartFreq(INT fsCore, const INT start_freq)
172 {
173 INT k0_min;
174
175 switch(fsCore){
176 case 8000: k0_min = 24; /* (3000 * nQmfChannels / fsSBR ) + 0.5 */
177 break;
178 case 11025: k0_min = 17; /* (3000 * nQmfChannels / fsSBR ) + 0.5 */
179 break;
180 case 12000: k0_min = 16; /* (3000 * nQmfChannels / fsSBR ) + 0.5 */
181 break;
182 case 16000: k0_min = 16; /* (4000 * nQmfChannels / fsSBR ) + 0.5 */
183 break;
184 case 22050: k0_min = 12; /* (4000 * nQmfChannels / fsSBR ) + 0.5 */
185 break;
186 case 24000: k0_min = 11; /* (4000 * nQmfChannels / fsSBR ) + 0.5 */
187 break;
188 case 32000: k0_min = 10; /* (5000 * nQmfChannels / fsSBR ) + 0.5 */
189 break;
190 case 44100: k0_min = 7; /* (5000 * nQmfChannels / fsSBR ) + 0.5 */
191 break;
192 case 48000: k0_min = 7; /* (5000 * nQmfChannels / fsSBR ) + 0.5 */
193 break;
194 case 96000: k0_min = 3; /* (5000 * nQmfChannels / fsSBR ) + 0.5 */
195 break;
196 default:
197 k0_min=11; /* illegal fs */
198 }
199
200
201 switch (fsCore) {
202
203 case 8000:
204 {
205 INT v_offset[]= {-8, -7, -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7};
206 return (k0_min + v_offset[start_freq]);
207 }
208 case 11025:
209 {
210 INT v_offset[]= {-5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 9, 11, 13};
211 return (k0_min + v_offset[start_freq]);
212 }
213 case 12000:
214 {
215 INT v_offset[]= {-5, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 9, 11, 13, 16};
216 return (k0_min + v_offset[start_freq]);
217 }
218 case 16000:
219 {
220 INT v_offset[]= {-6, -4, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 9, 11, 13, 16};
221 return (k0_min + v_offset[start_freq]);
222 }
223 case 22050:
224 case 24000:
225 case 32000:
226 {
227 INT v_offset[]= {-4, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 9, 11, 13, 16, 20};
228 return (k0_min + v_offset[start_freq]);
229 }
230 case 44100:
231 case 48000:
232 case 96000:
233 {
234 INT v_offset[]= {-2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 9, 11, 13, 16, 20, 24};
235 return (k0_min + v_offset[start_freq]);
236 }
237 default:
238 {
239 INT v_offset[]= {0, 1, 2, 3, 4, 5, 6, 7, 9, 11, 13, 16, 20, 24, 28, 33};
240 return (k0_min + v_offset[start_freq]);
241 }
242 }
243 } /* End getStartFreq */
244
245
246 /*******************************************************************************
247 Functionname: getStopFreq
248 *******************************************************************************
249 Description:
250
251 Arguments:
252
253 Return:
254 *******************************************************************************/
255 static INT
getStopFreq(INT fsCore,const INT stop_freq)256 getStopFreq(INT fsCore, const INT stop_freq)
257 {
258 INT result,i;
259 INT k1_min;
260 INT v_dstop[13];
261
262 INT *v_stop_freq = NULL;
263 INT v_stop_freq_16[14] = {48,49,50,51,52,54,55,56,57,59,60,61,63,64};
264 INT v_stop_freq_22[14] = {35,37,38,40,42,44,46,48,51,53,56,58,61,64};
265 INT v_stop_freq_24[14] = {32,34,36,38,40,42,44,46,49,52,55,58,61,64};
266 INT v_stop_freq_32[14] = {32,34,36,38,40,42,44,46,49,52,55,58,61,64};
267 INT v_stop_freq_44[14] = {23,25,27,29,32,34,37,40,43,47,51,55,59,64};
268 INT v_stop_freq_48[14] = {21,23,25,27,30,32,35,38,42,45,49,54,59,64};
269 INT v_stop_freq_64[14] = {20,22,24,26,29,31,34,37,41,45,49,54,59,64};
270 INT v_stop_freq_88[14] = {15,17,19,21,23,26,29,33,37,41,46,51,57,64};
271 INT v_stop_freq_96[14] = {13,15,17,19,21,24,27,31,35,39,44,50,57,64};
272 INT v_stop_freq_192[14] = {7, 8,10,12,14,16,19,23,27,32,38,46,54,64};
273
274 switch(fsCore){
275 case 8000: k1_min = 48;
276 v_stop_freq =v_stop_freq_16;
277 break;
278 case 11025: k1_min = 35;
279 v_stop_freq =v_stop_freq_22;
280 break;
281 case 12000: k1_min = 32;
282 v_stop_freq =v_stop_freq_24;
283 break;
284 case 16000: k1_min = 32;
285 v_stop_freq =v_stop_freq_32;
286 break;
287 case 22050: k1_min = 23;
288 v_stop_freq =v_stop_freq_44;
289 break;
290 case 24000: k1_min = 21;
291 v_stop_freq =v_stop_freq_48;
292 break;
293 case 32000: k1_min = 20;
294 v_stop_freq =v_stop_freq_64;
295 break;
296 case 44100: k1_min = 15;
297 v_stop_freq =v_stop_freq_88;
298 break;
299 case 48000: k1_min = 13;
300 v_stop_freq =v_stop_freq_96;
301 break;
302 case 96000: k1_min = 7;
303 v_stop_freq =v_stop_freq_192;
304 break;
305 default:
306 k1_min = 21; /* illegal fs */
307 }
308
309 /* if no valid core samplingrate is used this loop produces
310 a segfault, because v_stop_freq is not initialized */
311 /* Ensure increasing bandwidth */
312 for(i = 0; i <= 12; i++) {
313 v_dstop[i] = v_stop_freq[i+1] - v_stop_freq[i];
314 }
315
316 FDKsbrEnc_Shellsort_int(v_dstop, 13); /* Sort bandwidth changes */
317
318 result = k1_min;
319 for(i = 0; i < stop_freq; i++) {
320 result = result + v_dstop[i];
321 }
322
323 return(result);
324
325 }/* End getStopFreq */
326
327
328 /*******************************************************************************
329 Functionname: FDKsbrEnc_FindStartAndStopBand
330 *******************************************************************************
331 Description:
332
333 Arguments: srSbr SBR sampling freqency
334 srCore AAC core sampling freqency
335 noChannels Number of QMF channels
336 startFreq SBR start frequency in QMF bands
337 stopFreq SBR start frequency in QMF bands
338
339 *k0 Output parameter
340 *k2 Output parameter
341
342 Return: Error code (0 is OK)
343 *******************************************************************************/
344 INT
FDKsbrEnc_FindStartAndStopBand(const INT srSbr,const INT srCore,const INT noChannels,const INT startFreq,const INT stopFreq,INT * k0,INT * k2)345 FDKsbrEnc_FindStartAndStopBand(
346 const INT srSbr,
347 const INT srCore,
348 const INT noChannels,
349 const INT startFreq,
350 const INT stopFreq,
351 INT *k0,
352 INT *k2
353 )
354 {
355
356 /* Update startFreq struct */
357 *k0 = getStartFreq(srCore, startFreq);
358
359 /* Test if start freq is outside corecoder range */
360 if( srSbr*noChannels < *k0 * srCore ) {
361 return (1); /* raise the cross-over frequency and/or lower the number
362 of target bands per octave (or lower the sampling frequency) */
363 }
364
365 /*Update stopFreq struct */
366 if ( stopFreq < 14 ) {
367 *k2 = getStopFreq(srCore, stopFreq);
368 } else if( stopFreq == 14 ) {
369 *k2 = 2 * *k0;
370 } else {
371 *k2 = 3 * *k0;
372 }
373
374 /* limit to Nyqvist */
375 if (*k2 > noChannels) {
376 *k2 = noChannels;
377 }
378
379
380
381 /* Test for invalid k0 k2 combinations */
382 if ( (srCore == 22050) && ( (*k2 - *k0) > MAX_FREQ_COEFFS_FS44100 ) )
383 return (1); /* Number of bands exceeds valid range of MAX_FREQ_COEFFS for fs=44.1kHz */
384
385 if ( (srCore >= 24000) && ( (*k2 - *k0) > MAX_FREQ_COEFFS_FS48000 ) )
386 return (1); /* Number of bands exceeds valid range of MAX_FREQ_COEFFS for fs>=48kHz */
387
388 if ((*k2 - *k0) > MAX_FREQ_COEFFS)
389 return (1);/*Number of bands exceeds valid range of MAX_FREQ_COEFFS */
390
391 if ((*k2 - *k0) < 0)
392 return (1);/* Number of bands is negative */
393
394
395 return(0);
396 }
397
398 /*******************************************************************************
399 Functionname: FDKsbrEnc_UpdateFreqScale
400 *******************************************************************************
401 Description:
402
403 Arguments:
404
405 Return:
406 *******************************************************************************/
407 INT
FDKsbrEnc_UpdateFreqScale(UCHAR * v_k_master,INT * h_num_bands,const INT k0,const INT k2,const INT freqScale,const INT alterScale)408 FDKsbrEnc_UpdateFreqScale(
409 UCHAR *v_k_master,
410 INT *h_num_bands,
411 const INT k0,
412 const INT k2,
413 const INT freqScale,
414 const INT alterScale
415 )
416
417 {
418
419 INT b_p_o = 0; /* bands_per_octave */
420 FIXP_DBL warp = FL2FXCONST_DBL(0.0f);
421 INT dk = 0;
422
423 /* Internal variables */
424 INT k1 = 0, i;
425 INT num_bands0;
426 INT num_bands1;
427 INT diff_tot[MAX_OCTAVE + MAX_SECOND_REGION];
428 INT *diff0 = diff_tot;
429 INT *diff1 = diff_tot+MAX_OCTAVE;
430 INT k2_achived;
431 INT k2_diff;
432 INT incr = 0;
433
434 /* Init */
435 if (freqScale==1) b_p_o = 12;
436 if (freqScale==2) b_p_o = 10;
437 if (freqScale==3) b_p_o = 8;
438
439
440 if(freqScale > 0) /*Bark*/
441 {
442 if(alterScale==0)
443 warp = FL2FXCONST_DBL(0.5f); /* 1.0/(1.0*2.0) */
444 else
445 warp = FL2FXCONST_DBL(1.0f/2.6f); /* 1.0/(1.3*2.0); */
446
447
448 if(4*k2 >= 9*k0) /*two or more regions (how many times the basis band is copied)*/
449 {
450 k1=2*k0;
451
452 num_bands0=numberOfBands(b_p_o, k0, k1, FL2FXCONST_DBL(0.5f));
453 num_bands1=numberOfBands(b_p_o, k1, k2, warp);
454
455 CalcBands(diff0, k0, k1, num_bands0);/*CalcBands1 => diff0 */
456 FDKsbrEnc_Shellsort_int( diff0, num_bands0);/*SortBands sort diff0 */
457
458 if (diff0[0] == 0) /* too wide FB bands for target tuning */
459 {
460 return (1);/* raise the cross-over frequency and/or lower the number
461 of target bands per octave (or lower the sampling frequency */
462 }
463
464 cumSum(k0, diff0, num_bands0, v_k_master); /* cumsum */
465
466 CalcBands(diff1, k1, k2, num_bands1); /* CalcBands2 => diff1 */
467 FDKsbrEnc_Shellsort_int( diff1, num_bands1); /* SortBands sort diff1 */
468 if(diff0[num_bands0-1] > diff1[0]) /* max(1) > min(2) */
469 {
470 if(modifyBands(diff0[num_bands0-1],diff1, num_bands1))
471 return(1);
472 }
473
474 /* Add 2'nd region */
475 cumSum(k1, diff1, num_bands1, &v_k_master[num_bands0]);
476 *h_num_bands=num_bands0+num_bands1; /* Output nr of bands */
477
478 }
479 else /* one region */
480 {
481 k1=k2;
482
483 num_bands0=numberOfBands(b_p_o, k0, k1, FL2FXCONST_DBL(0.5f));
484 CalcBands(diff0, k0, k1, num_bands0);/* CalcBands1 => diff0 */
485 FDKsbrEnc_Shellsort_int( diff0, num_bands0); /* SortBands sort diff0 */
486
487 if (diff0[0] == 0) /* too wide FB bands for target tuning */
488 {
489 return (1); /* raise the cross-over frequency and/or lower the number
490 of target bands per octave (or lower the sampling frequency */
491 }
492
493 cumSum(k0, diff0, num_bands0, v_k_master);/* cumsum */
494 *h_num_bands=num_bands0; /* Output nr of bands */
495
496 }
497 }
498 else /* Linear mode */
499 {
500 if (alterScale==0) {
501 dk = 1;
502 num_bands0 = 2 * ((k2 - k0)/2); /* FLOOR to get to few number of bands*/
503 } else {
504 dk = 2;
505 num_bands0 = 2 * (((k2 - k0)/dk +1)/2); /* ROUND to get closest fit */
506 }
507
508 k2_achived = k0 + num_bands0*dk;
509 k2_diff = k2 - k2_achived;
510
511 for(i=0;i<num_bands0;i++)
512 diff_tot[i] = dk;
513
514 /* If linear scale wasn't achived */
515 /* and we got wide SBR are */
516 if (k2_diff < 0) {
517 incr = 1;
518 i = 0;
519 }
520
521 /* If linear scale wasn't achived */
522 /* and we got small SBR are */
523 if (k2_diff > 0) {
524 incr = -1;
525 i = num_bands0-1;
526 }
527
528 /* Adjust diff vector to get sepc. SBR range */
529 while (k2_diff != 0) {
530 diff_tot[i] = diff_tot[i] - incr;
531 i = i + incr;
532 k2_diff = k2_diff + incr;
533 }
534
535 cumSum(k0, diff_tot, num_bands0, v_k_master);/* cumsum */
536 *h_num_bands=num_bands0; /* Output nr of bands */
537
538 }
539
540 if (*h_num_bands < 1)
541 return(1); /*To small sbr area */
542
543 return (0);
544 }/* End FDKsbrEnc_UpdateFreqScale */
545
546 static INT
numberOfBands(INT b_p_o,INT start,INT stop,FIXP_DBL warp_factor)547 numberOfBands(INT b_p_o, INT start, INT stop, FIXP_DBL warp_factor)
548 {
549 INT result=0;
550 /* result = 2* (INT) ( (double)b_p_o * (double)(FDKlog((double)stop/(double)start)/FDKlog((double)2)) * (double)FX_DBL2FL(warp_factor) + 0.5); */
551 result = ( ( b_p_o * fMult( (CalcLdInt(stop) - CalcLdInt(start)), warp_factor) + (FL2FX_DBL(0.5f)>>LD_DATA_SHIFT)
552 ) >> ((DFRACT_BITS-1)-LD_DATA_SHIFT) ) << 1; /* do not optimize anymore (rounding!!) */
553
554 return(result);
555 }
556
557
558 static void
CalcBands(INT * diff,INT start,INT stop,INT num_bands)559 CalcBands(INT * diff, INT start , INT stop , INT num_bands)
560 {
561 INT i, qb, qe, qtmp;
562 INT previous;
563 INT current;
564 FIXP_DBL base, exp, tmp;
565
566 previous=start;
567 for(i=1; i<= num_bands; i++)
568 {
569 base = fDivNorm((FIXP_DBL)stop, (FIXP_DBL)start, &qb);
570 exp = fDivNorm((FIXP_DBL)i, (FIXP_DBL)num_bands, &qe);
571 tmp = fPow(base, qb, exp, qe, &qtmp);
572 tmp = fMult(tmp, (FIXP_DBL)(start<<24));
573 current = (INT)scaleValue(tmp, qtmp-23);
574 current = (current+1) >> 1; /* rounding*/
575 diff[i-1] = current-previous;
576 previous = current;
577 }
578
579 }/* End CalcBands */
580
581
582 static void
cumSum(INT start_value,INT * diff,INT length,UCHAR * start_adress)583 cumSum(INT start_value, INT* diff, INT length, UCHAR *start_adress)
584 {
585 INT i;
586 start_adress[0]=start_value;
587 for(i=1;i<=length;i++)
588 start_adress[i]=start_adress[i-1]+diff[i-1];
589 } /* End cumSum */
590
591
592 static INT
modifyBands(INT max_band_previous,INT * diff,INT length)593 modifyBands(INT max_band_previous, INT * diff, INT length)
594 {
595 INT change=max_band_previous-diff[0];
596
597 /* Limit the change so that the last band cannot get narrower than the first one */
598 if ( change > (diff[length-1] - diff[0]) / 2 )
599 change = (diff[length-1] - diff[0]) / 2;
600
601 diff[0] += change;
602 diff[length-1] -= change;
603 FDKsbrEnc_Shellsort_int(diff, length);
604
605 return(0);
606 }/* End modifyBands */
607
608
609 /*******************************************************************************
610 Functionname: FDKsbrEnc_UpdateHiRes
611 *******************************************************************************
612 Description:
613
614
615 Arguments:
616
617 Return:
618 *******************************************************************************/
619 INT
FDKsbrEnc_UpdateHiRes(UCHAR * h_hires,INT * num_hires,UCHAR * v_k_master,INT num_master,INT * xover_band)620 FDKsbrEnc_UpdateHiRes(
621 UCHAR *h_hires,
622 INT *num_hires,
623 UCHAR *v_k_master,
624 INT num_master,
625 INT *xover_band
626 )
627 {
628 INT i;
629 INT max1,max2;
630
631 if( (v_k_master[*xover_band] > 32 ) || /* v_k_master[*xover_band] > noQMFChannels(dualRate)/divider */
632 ( *xover_band > num_master ) ) {
633 /* xover_band error, too big for this startFreq. Will be clipped */
634
635 /* Calculate maximum value for xover_band */
636 max1=0;
637 max2=num_master;
638 while( (v_k_master[max1+1] < 32 ) && /* noQMFChannels(dualRate)/divider */
639 ( (max1+1) < max2) )
640 {
641 max1++;
642 }
643
644 *xover_band=max1;
645 }
646
647 *num_hires = num_master - *xover_band;
648 for(i = *xover_band; i <= num_master; i++)
649 {
650 h_hires[i - *xover_band] = v_k_master[i];
651 }
652
653 return (0);
654 }/* End FDKsbrEnc_UpdateHiRes */
655
656
657 /*******************************************************************************
658 Functionname: FDKsbrEnc_UpdateLoRes
659 *******************************************************************************
660 Description:
661
662 Arguments:
663
664 Return:
665 *******************************************************************************/
666 void
FDKsbrEnc_UpdateLoRes(UCHAR * h_lores,INT * num_lores,UCHAR * h_hires,INT num_hires)667 FDKsbrEnc_UpdateLoRes(UCHAR * h_lores, INT *num_lores, UCHAR * h_hires, INT num_hires)
668 {
669 INT i;
670
671 if(num_hires%2 == 0) /* if even number of hires bands */
672 {
673 *num_lores=num_hires/2;
674 /* Use every second lores=hires[0,2,4...] */
675 for(i=0;i<=*num_lores;i++)
676 h_lores[i]=h_hires[i*2];
677
678 }
679 else /* odd number of hires which means xover is odd */
680 {
681 *num_lores=(num_hires+1)/2;
682
683 /* Use lores=hires[0,1,3,5 ...] */
684 h_lores[0]=h_hires[0];
685 for(i=1;i<=*num_lores;i++)
686 {
687 h_lores[i]=h_hires[i*2-1];
688 }
689 }
690
691 }/* End FDKsbrEnc_UpdateLoRes */
692