1 /* 2 ** Copyright 2003-2010, VisualOn, Inc. 3 ** 4 ** Licensed under the Apache License, Version 2.0 (the "License"); 5 ** you may not use this file except in compliance with the License. 6 ** You may obtain a copy of the License at 7 ** 8 ** http://www.apache.org/licenses/LICENSE-2.0 9 ** 10 ** Unless required by applicable law or agreed to in writing, software 11 ** distributed under the License is distributed on an "AS IS" BASIS, 12 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 ** See the License for the specific language governing permissions and 14 ** limitations under the License. 15 */ 16 /******************************************************************************* 17 File: sf_estim.c 18 19 Content: Scale factor estimation functions 20 21 *******************************************************************************/ 22 23 #include "basic_op.h" 24 #include "oper_32b.h" 25 #include "sf_estim.h" 26 #include "quantize.h" 27 #include "bit_cnt.h" 28 #include "aac_rom.h" 29 30 static const Word16 MAX_SCF_DELTA = 60; 31 32 /*! 33 constants reference in comments 34 35 C0 = 6.75f; 36 C1 = -69.33295f; -16/3*log(MAX_QUANT+0.5-logCon)/log(2) 37 C2 = 4.0f; 38 C3 = 2.66666666f; 39 40 PE_C1 = 3.0f; log(8.0)/log(2) 41 PE_C2 = 1.3219281f; log(2.5)/log(2) 42 PE_C3 = 0.5593573f; 1-C2/C1 43 44 */ 45 46 #define FF_SQRT_BITS 7 47 #define FF_SQRT_TABLE_SIZE (1<<FF_SQRT_BITS - 1<<(FF_SQRT_BITS-2)) 48 #define COEF08_31 0x66666666 /* 0.8*(1 << 31) */ 49 #define PE_C1_8 24 /* PE_C1*8 */ 50 #define PE_C2_16 21 /* PE_C2*8/PE_C3 */ 51 #define PE_SCALE 0x059a /* 0.7 * (1 << (15 - 1 - 3))*/ 52 53 #define SCALE_ESTIMATE_COEF 0x5555 /* (8.8585/(4*log2(10))) * (1 << 15)*/ 54 55 /********************************************************************************* 56 * 57 * function name: formfac_sqrt 58 * description: calculates sqrt(x)/256 59 * 60 **********************************************************************************/ 61 __inline Word32 formfac_sqrt(Word32 x) 62 { 63 Word32 y; 64 Word32 preshift, postshift; 65 66 67 if (x==0) return 0; 68 preshift = norm_l(x) - (INT_BITS-1-FF_SQRT_BITS); 69 postshift = preshift >> 1; 70 preshift = postshift << 1; 71 postshift = postshift + 8; /* sqrt/256 */ 72 if(preshift >= 0) 73 y = x << preshift; /* now 1/4 <= y < 1 */ 74 else 75 y = x >> (-preshift); 76 y = formfac_sqrttable[y-32]; 77 78 if(postshift >= 0) 79 y = y >> postshift; 80 else 81 y = y << (-postshift); 82 83 return y; 84 } 85 86 87 /********************************************************************************* 88 * 89 * function name: CalcFormFactorChannel 90 * description: calculate the form factor one channel 91 * ffac(n) = sqrt(abs(X(k)) + sqrt(abs(X(k+1)) + .... 92 * 93 **********************************************************************************/ 94 static void 95 CalcFormFactorChannel(Word16 *logSfbFormFactor, 96 Word16 *sfbNRelevantLines, 97 Word16 *logSfbEnergy, 98 PSY_OUT_CHANNEL *psyOutChan) 99 { 100 Word32 sfbw, sfbw1; 101 Word32 i, j; 102 Word32 sfbOffs, sfb; 103 104 sfbw = sfbw1 = 0; 105 for (sfbOffs=0; sfbOffs<psyOutChan->sfbCnt; sfbOffs+=psyOutChan->sfbPerGroup){ 106 for (sfb=0; sfb<psyOutChan->maxSfbPerGroup; sfb++) { 107 i = sfbOffs+sfb; 108 109 if (psyOutChan->sfbEnergy[i] > psyOutChan->sfbThreshold[i]) { 110 Word32 accu, avgFormFactor,iSfbWidth; 111 Word32 *mdctSpec; 112 sfbw = psyOutChan->sfbOffsets[i+1] - psyOutChan->sfbOffsets[i]; 113 iSfbWidth = invSBF[(sfbw >> 2) - 1]; 114 mdctSpec = psyOutChan->mdctSpectrum + psyOutChan->sfbOffsets[i]; 115 accu = 0; 116 /* calc sum of sqrt(spec) */ 117 for (j=sfbw; j; j--) { 118 accu += formfac_sqrt(L_abs(*mdctSpec)); mdctSpec++; 119 } 120 logSfbFormFactor[i] = iLog4(accu); 121 logSfbEnergy[i] = iLog4(psyOutChan->sfbEnergy[i]); 122 avgFormFactor = fixmul(rsqrt(psyOutChan->sfbEnergy[i],INT_BITS), iSfbWidth); 123 avgFormFactor = rsqrt((Word32)avgFormFactor,INT_BITS) >> 10; 124 /* result is multiplied by 4 */ 125 if(avgFormFactor) 126 sfbNRelevantLines[i] = accu / avgFormFactor; 127 else 128 sfbNRelevantLines[i] = 0x7fff; 129 } 130 else { 131 /* set number of lines to zero */ 132 sfbNRelevantLines[i] = 0; 133 } 134 } 135 } 136 } 137 138 /********************************************************************************* 139 * 140 * function name: improveScf 141 * description: find better scalefactor with analysis by synthesis 142 * 143 **********************************************************************************/ 144 static Word16 improveScf(Word32 *spec, 145 Word16 sfbWidth, 146 Word32 thresh, 147 Word16 scf, 148 Word16 minScf, 149 Word32 *dist, 150 Word16 *minScfCalculated) 151 { 152 Word32 cnt; 153 Word32 sfbDist; 154 Word32 scfBest; 155 Word32 thresh125 = L_add(thresh, (thresh >> 2)); 156 157 scfBest = scf; 158 159 /* calc real distortion */ 160 sfbDist = calcSfbDist(spec, sfbWidth, scf); 161 *minScfCalculated = scf; 162 if(!sfbDist) 163 return scfBest; 164 165 if (sfbDist > thresh125) { 166 Word32 scfEstimated; 167 Word32 sfbDistBest; 168 scfEstimated = scf; 169 sfbDistBest = sfbDist; 170 171 cnt = 0; 172 while (sfbDist > thresh125 && (cnt < 3)) { 173 174 scf = scf + 1; 175 sfbDist = calcSfbDist(spec, sfbWidth, scf); 176 177 if (sfbDist < sfbDistBest) { 178 scfBest = scf; 179 sfbDistBest = sfbDist; 180 } 181 cnt = cnt + 1; 182 } 183 cnt = 0; 184 scf = scfEstimated; 185 sfbDist = sfbDistBest; 186 while ((sfbDist > thresh125) && (cnt < 1) && (scf > minScf)) { 187 188 scf = scf - 1; 189 sfbDist = calcSfbDist(spec, sfbWidth, scf); 190 191 if (sfbDist < sfbDistBest) { 192 scfBest = scf; 193 sfbDistBest = sfbDist; 194 } 195 *minScfCalculated = scf; 196 cnt = cnt + 1; 197 } 198 *dist = sfbDistBest; 199 } 200 else { 201 Word32 sfbDistBest; 202 Word32 sfbDistAllowed; 203 Word32 thresh08 = fixmul(COEF08_31, thresh); 204 sfbDistBest = sfbDist; 205 206 if (sfbDist < thresh08) 207 sfbDistAllowed = sfbDist; 208 else 209 sfbDistAllowed = thresh08; 210 for (cnt=0; cnt<3; cnt++) { 211 scf = scf + 1; 212 sfbDist = calcSfbDist(spec, sfbWidth, scf); 213 214 if (fixmul(COEF08_31,sfbDist) < sfbDistAllowed) { 215 *minScfCalculated = scfBest + 1; 216 scfBest = scf; 217 sfbDistBest = sfbDist; 218 } 219 } 220 *dist = sfbDistBest; 221 } 222 223 /* return best scalefactor */ 224 return scfBest; 225 } 226 227 /********************************************************************************* 228 * 229 * function name: countSingleScfBits 230 * description: count single scf bits in huffum 231 * 232 **********************************************************************************/ 233 static Word16 countSingleScfBits(Word16 scf, Word16 scfLeft, Word16 scfRight) 234 { 235 Word16 scfBits; 236 237 scfBits = bitCountScalefactorDelta(scfLeft - scf) + 238 bitCountScalefactorDelta(scf - scfRight); 239 240 return scfBits; 241 } 242 243 /********************************************************************************* 244 * 245 * function name: calcSingleSpecPe 246 * description: ldRatio = log2(en(n)) - 0,375*scfGain(n) 247 * nbits = 0.7*nLines*ldRation for ldRation >= c1 248 * nbits = 0.7*nLines*(c2 + c3*ldRatio) for ldRation < c1 249 * 250 **********************************************************************************/ 251 static Word16 calcSingleSpecPe(Word16 scf, Word16 sfbConstPePart, Word16 nLines) 252 { 253 Word32 specPe; 254 Word32 ldRatio; 255 Word32 scf3; 256 257 ldRatio = sfbConstPePart << 3; /* (sfbConstPePart -0.375*scf)*8 */ 258 scf3 = scf + scf + scf; 259 ldRatio = ldRatio - scf3; 260 261 if (ldRatio < PE_C1_8) { 262 /* 21 : 2*8*PE_C2, 2*PE_C3 ~ 1*/ 263 ldRatio = (ldRatio + PE_C2_16) >> 1; 264 } 265 specPe = nLines * ldRatio; 266 specPe = (specPe * PE_SCALE) >> 14; 267 268 return saturate(specPe); 269 } 270 271 272 /********************************************************************************* 273 * 274 * function name: countScfBitsDiff 275 * description: count different scf bits used 276 * 277 **********************************************************************************/ 278 static Word16 countScfBitsDiff(Word16 *scfOld, Word16 *scfNew, 279 Word16 sfbCnt, Word16 startSfb, Word16 stopSfb) 280 { 281 Word32 scfBitsDiff; 282 Word32 sfb, sfbLast; 283 Word32 sfbPrev, sfbNext; 284 285 scfBitsDiff = 0; 286 sfb = 0; 287 288 /* search for first relevant sfb */ 289 sfbLast = startSfb; 290 while (sfbLast < stopSfb && scfOld[sfbLast] == VOAAC_SHRT_MIN) { 291 292 sfbLast = sfbLast + 1; 293 } 294 /* search for previous relevant sfb and count diff */ 295 sfbPrev = startSfb - 1; 296 while ((sfbPrev>=0) && scfOld[sfbPrev] == VOAAC_SHRT_MIN) { 297 298 sfbPrev = sfbPrev - 1; 299 } 300 301 if (sfbPrev>=0) { 302 scfBitsDiff += bitCountScalefactorDelta(scfNew[sfbPrev] - scfNew[sfbLast]) - 303 bitCountScalefactorDelta(scfOld[sfbPrev] - scfOld[sfbLast]); 304 } 305 /* now loop through all sfbs and count diffs of relevant sfbs */ 306 for (sfb=sfbLast+1; sfb<stopSfb; sfb++) { 307 308 if (scfOld[sfb] != VOAAC_SHRT_MIN) { 309 scfBitsDiff += bitCountScalefactorDelta(scfNew[sfbLast] - scfNew[sfb]) - 310 bitCountScalefactorDelta(scfOld[sfbLast] - scfOld[sfb]); 311 sfbLast = sfb; 312 } 313 } 314 /* search for next relevant sfb and count diff */ 315 sfbNext = stopSfb; 316 while (sfbNext < sfbCnt && scfOld[sfbNext] == VOAAC_SHRT_MIN) { 317 318 sfbNext = sfbNext + 1; 319 } 320 321 if (sfbNext < sfbCnt) 322 scfBitsDiff += bitCountScalefactorDelta(scfNew[sfbLast] - scfNew[sfbNext]) - 323 bitCountScalefactorDelta(scfOld[sfbLast] - scfOld[sfbNext]); 324 325 return saturate(scfBitsDiff); 326 } 327 328 static Word16 calcSpecPeDiff(Word16 *scfOld, 329 Word16 *scfNew, 330 Word16 *sfbConstPePart, 331 Word16 *logSfbEnergy, 332 Word16 *logSfbFormFactor, 333 Word16 *sfbNRelevantLines, 334 Word16 startSfb, 335 Word16 stopSfb) 336 { 337 Word32 specPeDiff; 338 Word32 sfb; 339 340 specPeDiff = 0; 341 342 /* loop through all sfbs and count pe difference */ 343 for (sfb=startSfb; sfb<stopSfb; sfb++) { 344 345 346 if (scfOld[sfb] != VOAAC_SHRT_MIN) { 347 Word32 ldRatioOld, ldRatioNew; 348 Word32 scf3; 349 350 351 if (sfbConstPePart[sfb] == MIN_16) { 352 sfbConstPePart[sfb] = ((logSfbEnergy[sfb] - 353 logSfbFormFactor[sfb]) + 11-8*4+3) >> 2; 354 } 355 356 357 ldRatioOld = sfbConstPePart[sfb] << 3; 358 scf3 = scfOld[sfb] + scfOld[sfb] + scfOld[sfb]; 359 ldRatioOld = ldRatioOld - scf3; 360 ldRatioNew = sfbConstPePart[sfb] << 3; 361 scf3 = scfNew[sfb] + scfNew[sfb] + scfNew[sfb]; 362 ldRatioNew = ldRatioNew - scf3; 363 364 if (ldRatioOld < PE_C1_8) { 365 /* 21 : 2*8*PE_C2, 2*PE_C3 ~ 1*/ 366 ldRatioOld = (ldRatioOld + PE_C2_16) >> 1; 367 } 368 369 if (ldRatioNew < PE_C1_8) { 370 /* 21 : 2*8*PE_C2, 2*PE_C3 ~ 1*/ 371 ldRatioNew = (ldRatioNew + PE_C2_16) >> 1; 372 } 373 374 specPeDiff += sfbNRelevantLines[sfb] * (ldRatioNew - ldRatioOld); 375 } 376 } 377 378 specPeDiff = (specPeDiff * PE_SCALE) >> 14; 379 380 return saturate(specPeDiff); 381 } 382 383 384 /********************************************************************************* 385 * 386 * function name: assimilateSingleScf 387 * description: searched for single scalefactor bands, where the number of bits gained 388 * by using a smaller scfgain(n) is greater than the estimated increased 389 * bit demand 390 * 391 **********************************************************************************/ 392 static void assimilateSingleScf(PSY_OUT_CHANNEL *psyOutChan, 393 Word16 *scf, 394 Word16 *minScf, 395 Word32 *sfbDist, 396 Word16 *sfbConstPePart, 397 Word16 *logSfbEnergy, 398 Word16 *logSfbFormFactor, 399 Word16 *sfbNRelevantLines, 400 Word16 *minScfCalculated, 401 Flag restartOnSuccess) 402 { 403 Word16 sfbLast, sfbAct, sfbNext, scfAct, scfMin; 404 Word16 *scfLast, *scfNext; 405 Word32 sfbPeOld, sfbPeNew; 406 Word32 sfbDistNew; 407 Word32 j; 408 Flag success; 409 Word16 deltaPe, deltaPeNew, deltaPeTmp; 410 Word16 *prevScfLast = psyOutChan->prevScfLast; 411 Word16 *prevScfNext = psyOutChan->prevScfNext; 412 Word16 *deltaPeLast = psyOutChan->deltaPeLast; 413 Flag updateMinScfCalculated; 414 415 success = 0; 416 deltaPe = 0; 417 418 for(j=0;j<psyOutChan->sfbCnt;j++){ 419 prevScfLast[j] = MAX_16; 420 prevScfNext[j] = MAX_16; 421 deltaPeLast[j] = MAX_16; 422 } 423 424 sfbLast = -1; 425 sfbAct = -1; 426 sfbNext = -1; 427 scfLast = 0; 428 scfNext = 0; 429 scfMin = MAX_16; 430 do { 431 /* search for new relevant sfb */ 432 sfbNext = sfbNext + 1; 433 while (sfbNext < psyOutChan->sfbCnt && scf[sfbNext] == MIN_16) { 434 435 sfbNext = sfbNext + 1; 436 } 437 438 if ((sfbLast>=0) && (sfbAct>=0) && sfbNext < psyOutChan->sfbCnt) { 439 /* relevant scfs to the left and to the right */ 440 scfAct = scf[sfbAct]; 441 scfLast = scf + sfbLast; 442 scfNext = scf + sfbNext; 443 scfMin = min(*scfLast, *scfNext); 444 } 445 else { 446 447 if (sfbLast == -1 && (sfbAct>=0) && sfbNext < psyOutChan->sfbCnt) { 448 /* first relevant scf */ 449 scfAct = scf[sfbAct]; 450 scfLast = &scfAct; 451 scfNext = scf + sfbNext; 452 scfMin = *scfNext; 453 } 454 else { 455 456 if ((sfbLast>=0) && (sfbAct>=0) && sfbNext == psyOutChan->sfbCnt) { 457 /* last relevant scf */ 458 scfAct = scf[sfbAct]; 459 scfLast = scf + sfbLast; 460 scfNext = &scfAct; 461 scfMin = *scfLast; 462 } 463 } 464 } 465 466 if (sfbAct>=0) 467 scfMin = max(scfMin, minScf[sfbAct]); 468 469 if ((sfbAct >= 0) && 470 (sfbLast>=0 || sfbNext < psyOutChan->sfbCnt) && 471 scfAct > scfMin && 472 (*scfLast != prevScfLast[sfbAct] || 473 *scfNext != prevScfNext[sfbAct] || 474 deltaPe < deltaPeLast[sfbAct])) { 475 success = 0; 476 477 /* estimate required bits for actual scf */ 478 if (sfbConstPePart[sfbAct] == MIN_16) { 479 sfbConstPePart[sfbAct] = logSfbEnergy[sfbAct] - 480 logSfbFormFactor[sfbAct] + 11-8*4; /* 4*log2(6.75) - 32 */ 481 482 if (sfbConstPePart[sfbAct] < 0) 483 sfbConstPePart[sfbAct] = sfbConstPePart[sfbAct] + 3; 484 sfbConstPePart[sfbAct] = sfbConstPePart[sfbAct] >> 2; 485 } 486 487 sfbPeOld = calcSingleSpecPe(scfAct, sfbConstPePart[sfbAct], sfbNRelevantLines[sfbAct]) + 488 countSingleScfBits(scfAct, *scfLast, *scfNext); 489 deltaPeNew = deltaPe; 490 updateMinScfCalculated = 1; 491 do { 492 scfAct = scfAct - 1; 493 /* check only if the same check was not done before */ 494 495 if (scfAct < minScfCalculated[sfbAct]) { 496 sfbPeNew = calcSingleSpecPe(scfAct, sfbConstPePart[sfbAct], sfbNRelevantLines[sfbAct]) + 497 countSingleScfBits(scfAct, *scfLast, *scfNext); 498 /* use new scf if no increase in pe and 499 quantization error is smaller */ 500 deltaPeTmp = deltaPe + sfbPeNew - sfbPeOld; 501 502 if (deltaPeTmp < 10) { 503 sfbDistNew = calcSfbDist(psyOutChan->mdctSpectrum+ 504 psyOutChan->sfbOffsets[sfbAct], 505 (psyOutChan->sfbOffsets[sfbAct+1] - psyOutChan->sfbOffsets[sfbAct]), 506 scfAct); 507 if (sfbDistNew < sfbDist[sfbAct]) { 508 /* success, replace scf by new one */ 509 scf[sfbAct] = scfAct; 510 sfbDist[sfbAct] = sfbDistNew; 511 deltaPeNew = deltaPeTmp; 512 success = 1; 513 } 514 /* mark as already checked */ 515 516 if (updateMinScfCalculated) { 517 minScfCalculated[sfbAct] = scfAct; 518 } 519 } 520 else { 521 updateMinScfCalculated = 0; 522 } 523 } 524 525 } while (scfAct > scfMin); 526 deltaPe = deltaPeNew; 527 /* save parameters to avoid multiple computations of the same sfb */ 528 prevScfLast[sfbAct] = *scfLast; 529 prevScfNext[sfbAct] = *scfNext; 530 deltaPeLast[sfbAct] = deltaPe; 531 } 532 533 if (success && restartOnSuccess) { 534 /* start again at first sfb */ 535 sfbLast = -1; 536 sfbAct = -1; 537 sfbNext = -1; 538 scfLast = 0; 539 scfNext = 0; 540 scfMin = MAX_16; 541 success = 0; 542 } 543 else { 544 /* shift sfbs for next band */ 545 sfbLast = sfbAct; 546 sfbAct = sfbNext; 547 } 548 549 } while (sfbNext < psyOutChan->sfbCnt); 550 } 551 552 553 /********************************************************************************* 554 * 555 * function name: assimilateMultipleScf 556 * description: scalefactor difference reduction 557 * 558 **********************************************************************************/ 559 static void assimilateMultipleScf(PSY_OUT_CHANNEL *psyOutChan, 560 Word16 *scf, 561 Word16 *minScf, 562 Word32 *sfbDist, 563 Word16 *sfbConstPePart, 564 Word16 *logSfbEnergy, 565 Word16 *logSfbFormFactor, 566 Word16 *sfbNRelevantLines) 567 { 568 Word32 sfb, startSfb, stopSfb, scfMin, scfMax, scfAct; 569 Flag possibleRegionFound; 570 Word32 deltaScfBits; 571 Word32 deltaSpecPe; 572 Word32 deltaPe, deltaPeNew; 573 Word32 sfbCnt; 574 Word32 *sfbDistNew = psyOutChan->sfbDistNew; 575 Word16 *scfTmp = psyOutChan->prevScfLast; 576 577 deltaPe = 0; 578 sfbCnt = psyOutChan->sfbCnt; 579 580 /* calc min and max scalfactors */ 581 scfMin = MAX_16; 582 scfMax = MIN_16; 583 for (sfb=0; sfb<sfbCnt; sfb++) { 584 585 if (scf[sfb] != MIN_16) { 586 scfMin = min(scfMin, scf[sfb]); 587 scfMax = max(scfMax, scf[sfb]); 588 } 589 } 590 591 if (scfMax != MIN_16) { 592 593 scfAct = scfMax; 594 595 do { 596 scfAct = scfAct - 1; 597 for (sfb=0; sfb<sfbCnt; sfb++) { 598 scfTmp[sfb] = scf[sfb]; 599 } 600 stopSfb = 0; 601 do { 602 sfb = stopSfb; 603 604 while (sfb < sfbCnt && (scf[sfb] == MIN_16 || scf[sfb] <= scfAct)) { 605 sfb = sfb + 1; 606 } 607 startSfb = sfb; 608 sfb = sfb + 1; 609 610 while (sfb < sfbCnt && (scf[sfb] == MIN_16 || scf[sfb] > scfAct)) { 611 sfb = sfb + 1; 612 } 613 stopSfb = sfb; 614 615 possibleRegionFound = 0; 616 617 if (startSfb < sfbCnt) { 618 possibleRegionFound = 1; 619 for (sfb=startSfb; sfb<stopSfb; sfb++) { 620 621 if (scf[sfb]!=MIN_16) { 622 623 if (scfAct < minScf[sfb]) { 624 possibleRegionFound = 0; 625 break; 626 } 627 } 628 } 629 } 630 631 632 if (possibleRegionFound) { /* region found */ 633 634 /* replace scfs in region by scfAct */ 635 for (sfb=startSfb; sfb<stopSfb; sfb++) { 636 637 if (scfTmp[sfb]!=MIN_16) 638 scfTmp[sfb] = scfAct; 639 } 640 641 /* estimate change in bit demand for new scfs */ 642 deltaScfBits = countScfBitsDiff(scf,scfTmp,sfbCnt,startSfb,stopSfb); 643 deltaSpecPe = calcSpecPeDiff(scf, scfTmp, sfbConstPePart, 644 logSfbEnergy, logSfbFormFactor, sfbNRelevantLines, 645 startSfb, stopSfb); 646 deltaPeNew = deltaPe + deltaScfBits + deltaSpecPe; 647 648 649 if (deltaPeNew < 10) { 650 Word32 distOldSum, distNewSum; 651 652 /* quantize and calc sum of new distortion */ 653 distOldSum = 0; 654 distNewSum = 0; 655 for (sfb=startSfb; sfb<stopSfb; sfb++) { 656 657 if (scfTmp[sfb] != MIN_16) { 658 distOldSum = L_add(distOldSum, sfbDist[sfb]); 659 660 sfbDistNew[sfb] = calcSfbDist(psyOutChan->mdctSpectrum + 661 psyOutChan->sfbOffsets[sfb], 662 (psyOutChan->sfbOffsets[sfb+1] - psyOutChan->sfbOffsets[sfb]), 663 scfAct); 664 665 666 if (sfbDistNew[sfb] > psyOutChan->sfbThreshold[sfb]) { 667 distNewSum = distOldSum << 1; 668 break; 669 } 670 distNewSum = L_add(distNewSum, sfbDistNew[sfb]); 671 } 672 } 673 674 if (distNewSum < distOldSum) { 675 deltaPe = deltaPeNew; 676 for (sfb=startSfb; sfb<stopSfb; sfb++) { 677 678 if (scf[sfb]!=MIN_16) { 679 scf[sfb] = scfAct; 680 sfbDist[sfb] = sfbDistNew[sfb]; 681 } 682 } 683 } 684 } 685 } 686 } while (stopSfb <= sfbCnt); 687 } while (scfAct > scfMin); 688 } 689 } 690 691 /********************************************************************************* 692 * 693 * function name: EstimateScaleFactorsChannel 694 * description: estimate scale factors for one channel 695 * 696 **********************************************************************************/ 697 static void 698 EstimateScaleFactorsChannel(PSY_OUT_CHANNEL *psyOutChan, 699 Word16 *scf, 700 Word16 *globalGain, 701 Word16 *logSfbEnergy, 702 Word16 *logSfbFormFactor, 703 Word16 *sfbNRelevantLines) 704 { 705 Word32 i, j; 706 Word32 thresh, energy; 707 Word32 energyPart, thresholdPart; 708 Word32 scfInt, minScf, maxScf, maxAllowedScf, lastSf; 709 Word32 maxSpec; 710 Word32 *sfbDist = psyOutChan->sfbDist; 711 Word16 *minSfMaxQuant = psyOutChan->minSfMaxQuant; 712 Word16 *minScfCalculated = psyOutChan->minScfCalculated; 713 714 715 for (i=0; i<psyOutChan->sfbCnt; i++) { 716 Word32 sbfwith, sbfStart; 717 Word32 *mdctSpec; 718 thresh = psyOutChan->sfbThreshold[i]; 719 energy = psyOutChan->sfbEnergy[i]; 720 721 sbfStart = psyOutChan->sfbOffsets[i]; 722 sbfwith = psyOutChan->sfbOffsets[i+1] - sbfStart; 723 mdctSpec = psyOutChan->mdctSpectrum+sbfStart; 724 725 maxSpec = 0; 726 /* maximum of spectrum */ 727 for (j=sbfwith; j; j-- ) { 728 Word32 absSpec = L_abs(*mdctSpec); mdctSpec++; 729 maxSpec |= absSpec; 730 } 731 732 /* scfs without energy or with thresh>energy are marked with MIN_16 */ 733 scf[i] = MIN_16; 734 minSfMaxQuant[i] = MIN_16; 735 736 if ((maxSpec > 0) && (energy > thresh)) { 737 738 energyPart = logSfbFormFactor[i]; 739 thresholdPart = iLog4(thresh); 740 /* -20 = 4*log2(6.75) - 32 */ 741 scfInt = ((thresholdPart - energyPart - 20) * SCALE_ESTIMATE_COEF) >> 15; 742 743 minSfMaxQuant[i] = iLog4(maxSpec) - 68; /* 68 -16/3*log(MAX_QUANT+0.5-logCon)/log(2) + 1 */ 744 745 746 if (minSfMaxQuant[i] > scfInt) { 747 scfInt = minSfMaxQuant[i]; 748 } 749 750 /* find better scalefactor with analysis by synthesis */ 751 scfInt = improveScf(psyOutChan->mdctSpectrum+sbfStart, 752 sbfwith, 753 thresh, scfInt, minSfMaxQuant[i], 754 &sfbDist[i], &minScfCalculated[i]); 755 756 scf[i] = scfInt; 757 } 758 } 759 760 761 /* scalefactor differece reduction */ 762 { 763 Word16 sfbConstPePart[MAX_GROUPED_SFB]; 764 for(i=0;i<psyOutChan->sfbCnt;i++) { 765 sfbConstPePart[i] = MIN_16; 766 } 767 768 assimilateSingleScf(psyOutChan, scf, 769 minSfMaxQuant, sfbDist, sfbConstPePart, logSfbEnergy, 770 logSfbFormFactor, sfbNRelevantLines, minScfCalculated, 1); 771 772 assimilateMultipleScf(psyOutChan, scf, 773 minSfMaxQuant, sfbDist, sfbConstPePart, logSfbEnergy, 774 logSfbFormFactor, sfbNRelevantLines); 775 } 776 777 /* get max scalefac for global gain */ 778 maxScf = MIN_16; 779 minScf = MAX_16; 780 for (i=0; i<psyOutChan->sfbCnt; i++) { 781 782 if (maxScf < scf[i]) { 783 maxScf = scf[i]; 784 } 785 786 if ((scf[i] != MIN_16) && (minScf > scf[i])) { 787 minScf = scf[i]; 788 } 789 } 790 /* limit scf delta */ 791 maxAllowedScf = minScf + MAX_SCF_DELTA; 792 for(i=0; i<psyOutChan->sfbCnt; i++) { 793 794 if ((scf[i] != MIN_16) && (maxAllowedScf < scf[i])) { 795 scf[i] = maxAllowedScf; 796 } 797 } 798 /* new maxScf if any scf has been limited */ 799 800 if (maxAllowedScf < maxScf) { 801 maxScf = maxAllowedScf; 802 } 803 804 /* calc loop scalefactors */ 805 806 if (maxScf > MIN_16) { 807 *globalGain = maxScf; 808 lastSf = 0; 809 810 for(i=0; i<psyOutChan->sfbCnt; i++) { 811 812 if (scf[i] == MIN_16) { 813 scf[i] = lastSf; 814 /* set band explicitely to zero */ 815 for (j=psyOutChan->sfbOffsets[i]; j<psyOutChan->sfbOffsets[i+1]; j++) { 816 psyOutChan->mdctSpectrum[j] = 0; 817 } 818 } 819 else { 820 scf[i] = maxScf - scf[i]; 821 lastSf = scf[i]; 822 } 823 } 824 } 825 else{ 826 *globalGain = 0; 827 /* set spectrum explicitely to zero */ 828 for(i=0; i<psyOutChan->sfbCnt; i++) { 829 scf[i] = 0; 830 for (j=psyOutChan->sfbOffsets[i]; j<psyOutChan->sfbOffsets[i+1]; j++) { 831 psyOutChan->mdctSpectrum[j] = 0; 832 } 833 } 834 } 835 } 836 837 /********************************************************************************* 838 * 839 * function name: CalcFormFactor 840 * description: estimate Form factors for all channel 841 * 842 **********************************************************************************/ 843 void 844 CalcFormFactor(Word16 logSfbFormFactor[MAX_CHANNELS][MAX_GROUPED_SFB], 845 Word16 sfbNRelevantLines[MAX_CHANNELS][MAX_GROUPED_SFB], 846 Word16 logSfbEnergy[MAX_CHANNELS][MAX_GROUPED_SFB], 847 PSY_OUT_CHANNEL psyOutChannel[MAX_CHANNELS], 848 const Word16 nChannels) 849 { 850 Word16 j; 851 852 for (j=0; j<nChannels; j++) { 853 CalcFormFactorChannel(logSfbFormFactor[j], sfbNRelevantLines[j], logSfbEnergy[j], &psyOutChannel[j]); 854 } 855 } 856 857 /********************************************************************************* 858 * 859 * function name: EstimateScaleFactors 860 * description: estimate scale factors for all channel 861 * 862 **********************************************************************************/ 863 void 864 EstimateScaleFactors(PSY_OUT_CHANNEL psyOutChannel[MAX_CHANNELS], 865 QC_OUT_CHANNEL qcOutChannel[MAX_CHANNELS], 866 Word16 logSfbEnergy[MAX_CHANNELS][MAX_GROUPED_SFB], 867 Word16 logSfbFormFactor[MAX_CHANNELS][MAX_GROUPED_SFB], 868 Word16 sfbNRelevantLines[MAX_CHANNELS][MAX_GROUPED_SFB], 869 const Word16 nChannels) 870 { 871 Word16 j; 872 873 for (j=0; j<nChannels; j++) { 874 EstimateScaleFactorsChannel(&psyOutChannel[j], 875 qcOutChannel[j].scf, 876 &(qcOutChannel[j].globalGain), 877 logSfbEnergy[j], 878 logSfbFormFactor[j], 879 sfbNRelevantLines[j]); 880 } 881 } 882 883
