1 /* ------------------------------------------------------------------ 2 * Copyright (C) 1998-2009 PacketVideo 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 13 * express or implied. 14 * See the License for the specific language governing permissions 15 * and limitations under the License. 16 * ------------------------------------------------------------------- 17 */ 18 /* 19 20 Filename: ps_decorrelate.c 21 22 ------------------------------------------------------------------------------ 23 REVISION HISTORY 24 25 26 Who: Date: MM/DD/YYYY 27 Description: 28 29 ------------------------------------------------------------------------------ 30 INPUT AND OUTPUT DEFINITIONS 31 32 33 34 ------------------------------------------------------------------------------ 35 FUNCTION DESCRIPTION 36 37 Decorrelation 38 Decorrelation is achieved by means of all-pass filtering and delaying 39 Sub-band samples s_k(n) are converted into de-correlated sub-bands samples 40 d_k(n). k index for frequency, n time index 41 42 43 _______ ________ 44 | | _______ | | 45 ->|Hybrid | LF ---- | |->| Hybrid |--> 46 | Anal. | | | | | Synth | QMF -> L 47 ------- o----------------------->| | -------- Synth 48 QMF | s_k(n) |Stereo |--------------> 49 Anal. -------------------------->| | 50 _______ | | | | ________ 51 | | HF --o | ----------- |Process| | | 52 ->| Delay | | ->| |-------->| |->| Hybrid |--> 53 ------- | |decorrelate| d_k(n) | | | Synth | QMF -> R 54 ---->| |-------->| | -------- Synth 55 ----------- |_______|--------------> 56 57 58 Delay is introduced to compensate QMF bands not passed through Hybrid 59 Analysis 60 61 ------------------------------------------------------------------------------ 62 REQUIREMENTS 63 64 65 ------------------------------------------------------------------------------ 66 REFERENCES 67 68 SC 29 Software Copyright Licencing Disclaimer: 69 70 This software module was originally developed by 71 Coding Technologies 72 73 and edited by 74 - 75 76 in the course of development of the ISO/IEC 13818-7 and ISO/IEC 14496-3 77 standards for reference purposes and its performance may not have been 78 optimized. This software module is an implementation of one or more tools as 79 specified by the ISO/IEC 13818-7 and ISO/IEC 14496-3 standards. 80 ISO/IEC gives users free license to this software module or modifications 81 thereof for use in products claiming conformance to audiovisual and 82 image-coding related ITU Recommendations and/or ISO/IEC International 83 Standards. ISO/IEC gives users the same free license to this software module or 84 modifications thereof for research purposes and further ISO/IEC standardisation. 85 Those intending to use this software module in products are advised that its 86 use may infringe existing patents. ISO/IEC have no liability for use of this 87 software module or modifications thereof. Copyright is not released for 88 products that do not conform to audiovisual and image-coding related ITU 89 Recommendations and/or ISO/IEC International Standards. 90 The original developer retains full right to modify and use the code for its 91 own purpose, assign or donate the code to a third party and to inhibit third 92 parties from using the code for products that do not conform to audiovisual and 93 image-coding related ITU Recommendations and/or ISO/IEC International Standards. 94 This copyright notice must be included in all copies or derivative works. 95 Copyright (c) ISO/IEC 2003. 96 97 ------------------------------------------------------------------------------ 98 PSEUDO-CODE 99 100 ------------------------------------------------------------------------------ 101 */ 102 103 104 /*---------------------------------------------------------------------------- 105 ; INCLUDES 106 ----------------------------------------------------------------------------*/ 107 108 #ifdef AAC_PLUS 109 110 #ifdef PARAMETRICSTEREO 111 #include "pv_audio_type_defs.h" 112 #include "ps_decorrelate.h" 113 #include "aac_mem_funcs.h" 114 #include "ps_all_pass_filter_coeff.h" 115 #include "ps_pwr_transient_detection.h" 116 #include "ps_all_pass_fract_delay_filter.h" 117 #include "fxp_mul32.h" 118 119 /*---------------------------------------------------------------------------- 120 ; MACROS 121 ; Define module specific macros here 122 ----------------------------------------------------------------------------*/ 123 124 #ifndef min 125 #define min(a, b) ((a) < (b) ? (a) : (b)) 126 #endif 127 128 129 /*---------------------------------------------------------------------------- 130 ; DEFINES 131 ; Include all pre-processor statements here. Include conditional 132 ; compile variables also. 133 ----------------------------------------------------------------------------*/ 134 135 /*---------------------------------------------------------------------------- 136 ; LOCAL FUNCTION DEFINITIONS 137 ; Function Prototype declaration 138 ----------------------------------------------------------------------------*/ 139 140 141 /*---------------------------------------------------------------------------- 142 ; LOCAL STORE/BUFFER/POINTER DEFINITIONS 143 ; Variable declaration - defined here and used outside this module 144 ----------------------------------------------------------------------------*/ 145 146 147 /*---------------------------------------------------------------------------- 148 ; EXTERNAL FUNCTION REFERENCES 149 ; Declare functions defined elsewhere and referenced in this module 150 ----------------------------------------------------------------------------*/ 151 152 153 154 155 /*---------------------------------------------------------------------------- 156 ; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES 157 ; Declare variables used in this module but defined elsewhere 158 ----------------------------------------------------------------------------*/ 159 160 161 /*---------------------------------------------------------------------------- 162 ; FUNCTION CODE 163 ----------------------------------------------------------------------------*/ 164 void ps_decorrelate(STRUCT_PS_DEC *h_ps_dec, 165 Int32 *rIntBufferLeft, 166 Int32 *iIntBufferLeft, 167 Int32 *rIntBufferRight, 168 Int32 *iIntBufferRight, 169 Int32 scratch_mem[]) 170 { 171 Int32 sb; 172 Int32 maxsb; 173 Int32 gr; 174 Int32 sb_delay; 175 Int32 bin; 176 177 178 179 180 Int32 *aLeftReal; 181 Int32 *aLeftImag; 182 Int32 *aRightReal; 183 Int32 *aRightImag; 184 185 Int32 *aTransRatio = scratch_mem; /* use NO_BINS == 20 */ 186 187 188 Int32 ***pppRealDelayRBufferSer; 189 Int32 ***pppImagDelayRBufferSer; 190 191 Int32 **ppRealDelayBuffer; 192 Int32 **ppImagDelayBuffer; 193 194 const Int32(*ppFractDelayPhaseFactorSer)[3]; 195 /* 196 * Power transient estimation and detection 197 */ 198 199 200 ps_pwr_transient_detection(h_ps_dec, 201 rIntBufferLeft, 202 iIntBufferLeft, 203 aTransRatio); 204 205 206 aLeftReal = h_ps_dec->mHybridRealLeft; 207 aLeftImag = h_ps_dec->mHybridImagLeft; 208 aRightReal = h_ps_dec->mHybridRealRight; 209 aRightImag = h_ps_dec->mHybridImagRight; 210 211 pppRealDelayRBufferSer = h_ps_dec->aaaRealDelayRBufferSerSubQmf; 212 pppImagDelayRBufferSer = h_ps_dec->aaaImagDelayRBufferSerSubQmf; 213 214 ppRealDelayBuffer = h_ps_dec->aaRealDelayBufferSubQmf; 215 ppImagDelayBuffer = h_ps_dec->aaImagDelayBufferSubQmf; 216 217 218 219 ppFractDelayPhaseFactorSer = aaFractDelayPhaseFactorSerSubQmf; 220 221 222 /* 223 * NO_IID_GROUPS (SUBQMF_GROUPS (12) + QMF_GROUPS (10)) == 22 224 */ 225 226 for (gr = 0; gr < SUBQMF_GROUPS; gr++) /* 0 to 9 */ 227 { 228 Int32 rIn; 229 Int32 iIn; 230 Int32 *pt_rTmp; 231 Int32 *pt_iTmp; 232 Int32 rTmp; 233 Int32 cmplx; 234 Int32 tmp1, tmp2; 235 236 /* sb = subQMF/QMF subband */ 237 238 sb = groupBorders[gr]; 239 240 /* 241 * For lower subbands 242 * Apply all-pass filtering 243 * 244 */ 245 pt_rTmp = &ppRealDelayBuffer[sb][h_ps_dec->delayBufIndex]; 246 pt_iTmp = &ppImagDelayBuffer[sb][h_ps_dec->delayBufIndex]; 247 248 tmp1 = aLeftReal[sb]; 249 tmp2 = aLeftImag[sb]; 250 rIn = *pt_rTmp >> 1; 251 iIn = *pt_iTmp >> 1; 252 253 254 *pt_rTmp = tmp1; 255 *pt_iTmp = tmp2; 256 257 /* 258 * Fractional delay vector 259 * 260 * phi_fract(k) = exp(-j*pi*q_phi*f_center(k)) 0<= k <= SUBQMF_GROUPS 261 * 262 * q_phi = 0.39 263 * f_center(k) frequency vector 264 */ 265 266 cmplx = aFractDelayPhaseFactorSubQmf[sb]; 267 268 aRightReal[sb] = cmplx_mul32_by_16(rIn, -iIn, cmplx); 269 aRightImag[sb] = cmplx_mul32_by_16(iIn, rIn, cmplx); 270 271 ps_all_pass_fract_delay_filter_type_I(h_ps_dec->aDelayRBufIndexSer, 272 sb, 273 ppFractDelayPhaseFactorSer[sb], 274 pppRealDelayRBufferSer, 275 pppImagDelayRBufferSer, 276 &aRightReal[sb], 277 &aRightImag[sb]); 278 279 bin = bins2groupMap[gr]; 280 rTmp = aTransRatio[bin]; 281 282 if (rTmp != 0x7FFFFFFF) 283 { 284 aRightReal[sb] = fxp_mul32_Q31(rTmp, aRightReal[sb]) << 1; 285 aRightImag[sb] = fxp_mul32_Q31(rTmp, aRightImag[sb]) << 1; 286 } 287 288 289 } /* gr */ 290 291 aLeftReal = rIntBufferLeft; 292 aLeftImag = iIntBufferLeft; 293 aRightReal = rIntBufferRight; 294 aRightImag = iIntBufferRight; 295 296 pppRealDelayRBufferSer = h_ps_dec->aaaRealDelayRBufferSerQmf; 297 pppImagDelayRBufferSer = h_ps_dec->aaaImagDelayRBufferSerQmf; 298 299 ppRealDelayBuffer = h_ps_dec->aaRealDelayBufferQmf; 300 ppImagDelayBuffer = h_ps_dec->aaImagDelayBufferQmf; 301 302 303 304 ppFractDelayPhaseFactorSer = aaFractDelayPhaseFactorSerQmf; 305 306 307 for (gr = SUBQMF_GROUPS; gr < NO_BINS; gr++) /* 10 to 20 */ 308 { 309 310 maxsb = min(h_ps_dec->usb, groupBorders[gr+1]); 311 312 /* sb = subQMF/QMF subband */ 313 314 for (sb = groupBorders[gr]; sb < maxsb; sb++) 315 { 316 317 Int32 rIn, iIn; 318 Int32 *pt_rTmp, *pt_iTmp; 319 Int32 cmplx; 320 Int32 tmp1, tmp2; 321 Int32 rTmp; 322 323 324 sb_delay = sb - NO_QMF_CHANNELS_IN_HYBRID; /* NO_QMF_CHANNELS_IN_HYBRID == 3 */ 325 326 /* 327 * For lower subbands 328 * Apply all-pass filtering 329 * 330 */ 331 pt_rTmp = &ppRealDelayBuffer[sb_delay][h_ps_dec->delayBufIndex]; 332 pt_iTmp = &ppImagDelayBuffer[sb_delay][h_ps_dec->delayBufIndex]; 333 334 rIn = *pt_rTmp >> 1; 335 iIn = *pt_iTmp >> 1; 336 337 tmp1 = aLeftReal[sb]; 338 tmp2 = aLeftImag[sb]; 339 *pt_rTmp = tmp1; 340 *pt_iTmp = tmp2; 341 342 /* 343 * Fractional delay vector 344 * 345 * phi_fract(k) = exp(-j*pi*q_phi*f_center(k)) 0<= k <= SUBQMF_GROUPS 346 * 347 * q_phi = 0.39 348 * f_center(k) frequency vector 349 */ 350 351 cmplx = aFractDelayPhaseFactor[sb_delay]; 352 aRightReal[sb] = cmplx_mul32_by_16(rIn, -iIn, cmplx); 353 aRightImag[sb] = cmplx_mul32_by_16(iIn, rIn, cmplx); 354 355 ps_all_pass_fract_delay_filter_type_II(h_ps_dec->aDelayRBufIndexSer, 356 sb_delay, 357 ppFractDelayPhaseFactorSer[sb_delay], 358 pppRealDelayRBufferSer, 359 pppImagDelayRBufferSer, 360 &aRightReal[sb], 361 &aRightImag[sb], 362 sb); 363 364 rTmp = aTransRatio[gr-2]; 365 if (rTmp != 0x7FFFFFFF) 366 { 367 aRightReal[sb] = fxp_mul32_Q31(rTmp, aRightReal[sb]) << 1; 368 aRightImag[sb] = fxp_mul32_Q31(rTmp, aRightImag[sb]) << 1; 369 } 370 371 372 } /* sb */ 373 374 } 375 376 377 maxsb = min(h_ps_dec->usb, 35); /* 35 == groupBorders[NO_BINS + 1] */ 378 379 /* sb = subQMF/QMF subband */ 380 { 381 Int32 factor = aTransRatio[NO_BINS-2]; 382 383 for (sb = 23; sb < maxsb; sb++) /* 23 == groupBorders[NO_BINS] */ 384 { 385 386 Int32 tmp, tmp2; 387 Int32 *pt_rTmp, *pt_iTmp; 388 389 sb_delay = sb - NO_QMF_CHANNELS_IN_HYBRID; /* == 3 */ 390 391 /* 392 * For the Upper Bands apply delay only 393 * -D(k) 394 * Apply Delay H_k(z) = z , D(k) == 1 or 14 395 * 396 */ 397 Int32 k = sb - NO_ALLPASS_CHANNELS; /* == 23 */ 398 399 400 pt_rTmp = &ppRealDelayBuffer[sb_delay][h_ps_dec->aDelayBufIndex[ k]]; 401 pt_iTmp = &ppImagDelayBuffer[sb_delay][h_ps_dec->aDelayBufIndex[ k]]; 402 403 if (++h_ps_dec->aDelayBufIndex[ k] >= LONG_DELAY) /* == 14 */ 404 { 405 h_ps_dec->aDelayBufIndex[ k] = 0; 406 } 407 408 409 tmp = *pt_rTmp; 410 tmp2 = *pt_iTmp; 411 412 if (aTransRatio[NO_BINS-2] < 0x7FFFFFFF) 413 { 414 aRightReal[sb] = fxp_mul32_Q31(factor, tmp) << 1; 415 aRightImag[sb] = fxp_mul32_Q31(factor, tmp2) << 1; 416 } 417 else 418 { 419 aRightReal[sb] = tmp; 420 aRightImag[sb] = tmp2; 421 } 422 423 424 tmp = aLeftReal[sb]; 425 tmp2 = aLeftImag[sb]; 426 *pt_rTmp = tmp; 427 *pt_iTmp = tmp2; 428 429 430 } /* sb */ 431 } 432 433 434 maxsb = min(h_ps_dec->usb, 64); /* 64 == groupBorders[NO_BINS+2] */ 435 436 /* sb = subQMF/QMF subband */ 437 438 { 439 440 for (sb = 35; sb < maxsb; sb++) /* 35 == groupBorders[NO_BINS+1] */ 441 { 442 443 Int32 *pt_rTmp, *pt_iTmp; 444 445 sb_delay = sb - NO_QMF_CHANNELS_IN_HYBRID; /* == 3 */ 446 447 /* 448 * For the Upper Bands apply delay only 449 * -D(k) 450 * Apply Delay H_k(z) = z , D(k) == 1 or 14 451 * 452 */ 453 454 pt_rTmp = &ppRealDelayBuffer[sb_delay][0]; 455 pt_iTmp = &ppImagDelayBuffer[sb_delay][0]; 456 457 aRightReal[sb] = *pt_rTmp; 458 aRightImag[sb] = *pt_iTmp; 459 460 461 if (aTransRatio[NO_BINS-1] < 0x7FFFFFFF) 462 { 463 aRightReal[sb] = fxp_mul32_Q31(aTransRatio[NO_BINS-1], aRightReal[sb]) << 1; 464 aRightImag[sb] = fxp_mul32_Q31(aTransRatio[NO_BINS-1], aRightImag[sb]) << 1; 465 } 466 467 *pt_rTmp = aLeftReal[sb]; 468 *pt_iTmp = aLeftImag[sb]; 469 470 471 } /* sb */ 472 } 473 474 475 if (++h_ps_dec->delayBufIndex >= DELAY_ALLPASS) 476 { 477 h_ps_dec->delayBufIndex = 0; 478 } 479 480 if (++h_ps_dec->aDelayRBufIndexSer[0] >= 3) 481 { 482 h_ps_dec->aDelayRBufIndexSer[0] = 0; 483 } 484 if (++h_ps_dec->aDelayRBufIndexSer[1] >= 4) 485 { 486 h_ps_dec->aDelayRBufIndexSer[1] = 0; 487 } 488 if (++h_ps_dec->aDelayRBufIndexSer[2] >= 5) 489 { 490 h_ps_dec->aDelayRBufIndexSer[2] = 0; 491 } 492 493 494 } /* END deCorrelate */ 495 #endif 496 497 498 #endif 499 500
