1 /* ----------------------------------------------------------------------------- 2 Software License for The Fraunhofer FDK AAC Codec Library for Android 3 4 Copyright 1995 - 2018 Fraunhofer-Gesellschaft zur Frderung der angewandten 5 Forschung e.V. All rights reserved. 6 7 1. INTRODUCTION 8 The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software 9 that implements the MPEG Advanced Audio Coding ("AAC") encoding and decoding 10 scheme for digital audio. This FDK AAC Codec software is intended to be used on 11 a wide variety of Android devices. 12 13 AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient 14 general perceptual audio codecs. AAC-ELD is considered the best-performing 15 full-bandwidth communications codec by independent studies and is widely 16 deployed. AAC has been standardized by ISO and IEC as part of the MPEG 17 specifications. 18 19 Patent licenses for necessary patent claims for the FDK AAC Codec (including 20 those of Fraunhofer) may be obtained through Via Licensing 21 (www.vialicensing.com) or through the respective patent owners individually for 22 the purpose of encoding or decoding bit streams in products that are compliant 23 with the ISO/IEC MPEG audio standards. Please note that most manufacturers of 24 Android devices already license these patent claims through Via Licensing or 25 directly from the patent owners, and therefore FDK AAC Codec software may 26 already be covered under those patent licenses when it is used for those 27 licensed purposes only. 28 29 Commercially-licensed AAC software libraries, including floating-point versions 30 with enhanced sound quality, are also available from Fraunhofer. Users are 31 encouraged to check the Fraunhofer website for additional applications 32 information and documentation. 33 34 2. COPYRIGHT LICENSE 35 36 Redistribution and use in source and binary forms, with or without modification, 37 are permitted without payment of copyright license fees provided that you 38 satisfy the following conditions: 39 40 You must retain the complete text of this software license in redistributions of 41 the FDK AAC Codec or your modifications thereto in source code form. 42 43 You must retain the complete text of this software license in the documentation 44 and/or other materials provided with redistributions of the FDK AAC Codec or 45 your modifications thereto in binary form. You must make available free of 46 charge copies of the complete source code of the FDK AAC Codec and your 47 modifications thereto to recipients of copies in binary form. 48 49 The name of Fraunhofer may not be used to endorse or promote products derived 50 from this library without prior written permission. 51 52 You may not charge copyright license fees for anyone to use, copy or distribute 53 the FDK AAC Codec software or your modifications thereto. 54 55 Your modified versions of the FDK AAC Codec must carry prominent notices stating 56 that you changed the software and the date of any change. For modified versions 57 of the FDK AAC Codec, the term "Fraunhofer FDK AAC Codec Library for Android" 58 must be replaced by the term "Third-Party Modified Version of the Fraunhofer FDK 59 AAC Codec Library for Android." 60 61 3. NO PATENT LICENSE 62 63 NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without 64 limitation the patents of Fraunhofer, ARE GRANTED BY THIS SOFTWARE LICENSE. 65 Fraunhofer provides no warranty of patent non-infringement with respect to this 66 software. 67 68 You may use this FDK AAC Codec software or modifications thereto only for 69 purposes that are authorized by appropriate patent licenses. 70 71 4. DISCLAIMER 72 73 This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright 74 holders and contributors "AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, 75 including but not limited to the implied warranties of merchantability and 76 fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 77 CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, 78 or consequential damages, including but not limited to procurement of substitute 79 goods or services; loss of use, data, or profits, or business interruption, 80 however caused and on any theory of liability, whether in contract, strict 81 liability, or tort (including negligence), arising in any way out of the use of 82 this software, even if advised of the possibility of such damage. 83 84 5. CONTACT INFORMATION 85 86 Fraunhofer Institute for Integrated Circuits IIS 87 Attention: Audio and Multimedia Departments - FDK AAC LL 88 Am Wolfsmantel 33 89 91058 Erlangen, Germany 90 91 www.iis.fraunhofer.de/amm 92 amm-info (at) iis.fraunhofer.de 93 ----------------------------------------------------------------------------- */ 94 95 /**************************** AAC decoder library ****************************** 96 97 Author(s): 98 99 Description: 100 101 *******************************************************************************/ 102 103 /*! 104 \file 105 \brief RVLC Decoder 106 \author Robert Weidner 107 */ 108 109 #include "rvlc.h" 110 111 #include "block.h" 112 113 #include "aac_rom.h" 114 #include "rvlcbit.h" 115 #include "rvlcconceal.h" 116 #include "aacdec_hcr.h" 117 118 /*--------------------------------------------------------------------------------------------- 119 function: rvlcInit 120 121 description: init RVLC by data from channelinfo, which was decoded 122 previously and set up pointers 123 ----------------------------------------------------------------------------------------------- 124 input: - pointer rvlc structure 125 - pointer channel info structure 126 - pointer bitstream structure 127 ----------------------------------------------------------------------------------------------- 128 return: - 129 -------------------------------------------------------------------------------------------- 130 */ 131 132 static void rvlcInit(CErRvlcInfo *pRvlc, 133 CAacDecoderChannelInfo *pAacDecoderChannelInfo, 134 HANDLE_FDK_BITSTREAM bs) { 135 /* RVLC common initialization part 2 of 2 */ 136 SHORT *pScfEsc = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfEsc; 137 SHORT *pScfFwd = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd; 138 SHORT *pScfBwd = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd; 139 SHORT *pScaleFactor = pAacDecoderChannelInfo->pDynData->aScaleFactor; 140 int bnds; 141 142 pAacDecoderChannelInfo->pDynData->specificTo.aac.rvlcIntensityUsed = 0; 143 144 pRvlc->numDecodedEscapeWordsEsc = 0; 145 pRvlc->numDecodedEscapeWordsFwd = 0; 146 pRvlc->numDecodedEscapeWordsBwd = 0; 147 148 pRvlc->intensity_used = 0; 149 pRvlc->errorLogRvlc = 0; 150 151 pRvlc->conceal_max = CONCEAL_MAX_INIT; 152 pRvlc->conceal_min = CONCEAL_MIN_INIT; 153 154 pRvlc->conceal_max_esc = CONCEAL_MAX_INIT; 155 pRvlc->conceal_min_esc = CONCEAL_MIN_INIT; 156 157 pRvlc->pHuffTreeRvlcEscape = aHuffTreeRvlcEscape; 158 pRvlc->pHuffTreeRvlCodewds = aHuffTreeRvlCodewds; 159 160 /* init scf arrays (for savety (in case of there are only zero codebooks)) */ 161 for (bnds = 0; bnds < RVLC_MAX_SFB; bnds++) { 162 pScfFwd[bnds] = 0; 163 pScfBwd[bnds] = 0; 164 pScfEsc[bnds] = 0; 165 pScaleFactor[bnds] = 0; 166 } 167 168 /* set base bitstream ptr to the RVL-coded part (start of RVLC data (ESC 2)) 169 */ 170 FDKsyncCache(bs); 171 172 pRvlc->bitstreamIndexRvlFwd = FDKgetBitCnt( 173 bs); /* first bit within RVL coded block as start address for forward 174 decoding */ 175 pRvlc->bitstreamIndexRvlBwd = FDKgetBitCnt(bs) + pRvlc->length_of_rvlc_sf - 176 1; /* last bit within RVL coded block as start 177 address for backward decoding */ 178 179 /* skip RVLC-bitstream-part -- pointing now to escapes (if present) or to TNS 180 * data (if present) */ 181 FDKpushFor(bs, pRvlc->length_of_rvlc_sf); 182 183 if (pRvlc->sf_escapes_present != 0) { 184 /* locate internal bitstream ptr at escapes (which is the second part) */ 185 FDKsyncCache(bs); 186 pRvlc->bitstreamIndexEsc = FDKgetBitCnt(bs); 187 188 /* skip escapeRVLC-bitstream-part -- pointing to TNS data (if present) to 189 * make decoder continue */ 190 /* decoding of RVLC should work despite this second pushFor during 191 * initialization because */ 192 /* bitstream initialization is valid for both ESC2 data parts (RVL-coded 193 * values and ESC-coded values) */ 194 FDKpushFor(bs, pRvlc->length_of_rvlc_escapes); 195 } 196 } 197 198 /*--------------------------------------------------------------------------------------------- 199 function: rvlcCheckIntensityCb 200 201 description: Check if a intensity codebook is used in the current channel. 202 ----------------------------------------------------------------------------------------------- 203 input: - pointer rvlc structure 204 - pointer channel info structure 205 ----------------------------------------------------------------------------------------------- 206 output: - intensity_used: 0 no intensity codebook is used 207 1 intensity codebook is used 208 ----------------------------------------------------------------------------------------------- 209 return: - 210 -------------------------------------------------------------------------------------------- 211 */ 212 213 static void rvlcCheckIntensityCb( 214 CErRvlcInfo *pRvlc, CAacDecoderChannelInfo *pAacDecoderChannelInfo) { 215 int group, band, bnds; 216 217 pRvlc->intensity_used = 0; 218 219 for (group = 0; group < pRvlc->numWindowGroups; group++) { 220 for (band = 0; band < pRvlc->maxSfbTransmitted; band++) { 221 bnds = 16 * group + band; 222 if ((pAacDecoderChannelInfo->pDynData->aCodeBook[bnds] == 223 INTENSITY_HCB) || 224 (pAacDecoderChannelInfo->pDynData->aCodeBook[bnds] == 225 INTENSITY_HCB2)) { 226 pRvlc->intensity_used = 1; 227 break; 228 } 229 } 230 } 231 } 232 233 /*--------------------------------------------------------------------------------------------- 234 function: rvlcDecodeEscapeWord 235 236 description: Decode a huffman coded RVLC Escape-word. This value is part 237 of a DPCM coded scalefactor. 238 ----------------------------------------------------------------------------------------------- 239 input: - pointer rvlc structure 240 ----------------------------------------------------------------------------------------------- 241 return: - a single RVLC-Escape value which had to be applied to a 242 DPCM value (which has a absolute value of 7) 243 -------------------------------------------------------------------------------------------- 244 */ 245 246 static SCHAR rvlcDecodeEscapeWord(CErRvlcInfo *pRvlc, HANDLE_FDK_BITSTREAM bs) { 247 int i; 248 SCHAR value; 249 UCHAR carryBit; 250 UINT treeNode; 251 UINT branchValue; 252 UINT branchNode; 253 254 INT *pBitstreamIndexEsc; 255 const UINT *pEscTree; 256 257 pEscTree = pRvlc->pHuffTreeRvlcEscape; 258 pBitstreamIndexEsc = &(pRvlc->bitstreamIndexEsc); 259 treeNode = *pEscTree; /* init at starting node */ 260 261 for (i = MAX_LEN_RVLC_ESCAPE_WORD - 1; i >= 0; i--) { 262 carryBit = rvlcReadBitFromBitstream(bs, /* get next bit */ 263 pBitstreamIndexEsc, FWD); 264 265 CarryBitToBranchValue(carryBit, /* huffman decoding, do a single step in 266 huffman decoding tree */ 267 treeNode, &branchValue, &branchNode); 268 269 if ((branchNode & TEST_BIT_10) == 270 TEST_BIT_10) { /* test bit 10 ; if set --> a RVLC-escape-word is 271 completely decoded */ 272 value = (SCHAR)branchNode & CLR_BIT_10; 273 pRvlc->length_of_rvlc_escapes -= (MAX_LEN_RVLC_ESCAPE_WORD - i); 274 275 if (pRvlc->length_of_rvlc_escapes < 0) { 276 pRvlc->errorLogRvlc |= RVLC_ERROR_ALL_ESCAPE_WORDS_INVALID; 277 value = -1; 278 } 279 280 return value; 281 } else { 282 treeNode = *( 283 pEscTree + 284 branchValue); /* update treeNode for further step in decoding tree */ 285 } 286 } 287 288 pRvlc->errorLogRvlc |= RVLC_ERROR_ALL_ESCAPE_WORDS_INVALID; 289 290 return -1; /* should not be reached */ 291 } 292 293 /*--------------------------------------------------------------------------------------------- 294 function: rvlcDecodeEscapes 295 296 description: Decodes all huffman coded RVLC Escape Words. 297 Here a difference to the pseudo-code-implementation from 298 standard can be found. A while loop (and not two nested for loops) is used for 299 two reasons: 300 301 1. The plain huffman encoded escapes are decoded before the 302 RVL-coded scalefactors. Therefore the escapes are present in the second step 303 when decoding the RVL-coded-scalefactor values in forward 304 and backward direction. 305 306 When the RVL-coded scalefactors are decoded and there a 307 escape is needed, then it is just taken out of the array in ascending order. 308 309 2. It's faster. 310 ----------------------------------------------------------------------------------------------- 311 input: - pointer rvlc structure 312 - handle to FDK bitstream 313 ----------------------------------------------------------------------------------------------- 314 return: - 0 ok the decoded escapes seem to be valid 315 - 1 error there was a error detected during decoding escapes 316 --> all escapes are invalid 317 -------------------------------------------------------------------------------------------- 318 */ 319 320 static void rvlcDecodeEscapes(CErRvlcInfo *pRvlc, SHORT *pEsc, 321 HANDLE_FDK_BITSTREAM bs) { 322 SCHAR escWord; 323 SCHAR escCnt = 0; 324 SHORT *pEscBitCntSum; 325 326 pEscBitCntSum = &(pRvlc->length_of_rvlc_escapes); 327 328 /* Decode all RVLC-Escape words with a plain Huffman-Decoder */ 329 while (*pEscBitCntSum > 0) { 330 escWord = rvlcDecodeEscapeWord(pRvlc, bs); 331 332 if (escWord >= 0) { 333 pEsc[escCnt] = escWord; 334 escCnt++; 335 } else { 336 pRvlc->errorLogRvlc |= RVLC_ERROR_ALL_ESCAPE_WORDS_INVALID; 337 pRvlc->numDecodedEscapeWordsEsc = escCnt; 338 339 return; 340 } 341 } /* all RVLC escapes decoded */ 342 343 pRvlc->numDecodedEscapeWordsEsc = escCnt; 344 } 345 346 /*--------------------------------------------------------------------------------------------- 347 function: decodeRVLCodeword 348 349 description: Decodes a RVL-coded dpcm-word (-part). 350 ----------------------------------------------------------------------------------------------- 351 input: - FDK bitstream handle 352 - pointer rvlc structure 353 ----------------------------------------------------------------------------------------------- 354 return: - a dpcm value which is within range [0,1,..,14] in case of 355 no errors. The offset of 7 must be subtracted to get a valid dpcm scalefactor 356 value. In case of errors a forbidden codeword is detected --> returning -1 357 -------------------------------------------------------------------------------------------- 358 */ 359 360 SCHAR decodeRVLCodeword(HANDLE_FDK_BITSTREAM bs, CErRvlcInfo *pRvlc) { 361 int i; 362 SCHAR value; 363 UCHAR carryBit; 364 UINT branchValue; 365 UINT branchNode; 366 367 const UINT *pRvlCodeTree = pRvlc->pHuffTreeRvlCodewds; 368 UCHAR direction = pRvlc->direction; 369 INT *pBitstrIndxRvl = pRvlc->pBitstrIndxRvl_RVL; 370 UINT treeNode = *pRvlCodeTree; 371 372 for (i = MAX_LEN_RVLC_CODE_WORD - 1; i >= 0; i--) { 373 carryBit = rvlcReadBitFromBitstream(bs, /* get next bit */ 374 pBitstrIndxRvl, direction); 375 376 CarryBitToBranchValue(carryBit, /* huffman decoding, do a single step in 377 huffman decoding tree */ 378 treeNode, &branchValue, &branchNode); 379 380 if ((branchNode & TEST_BIT_10) == 381 TEST_BIT_10) { /* test bit 10 ; if set --> a 382 RVLC-codeword is completely decoded 383 */ 384 value = (SCHAR)(branchNode & CLR_BIT_10); 385 *pRvlc->pRvlBitCnt_RVL -= (MAX_LEN_RVLC_CODE_WORD - i); 386 387 /* check available bits for decoding */ 388 if (*pRvlc->pRvlBitCnt_RVL < 0) { 389 if (direction == FWD) { 390 pRvlc->errorLogRvlc |= RVLC_ERROR_RVL_SUM_BIT_COUNTER_BELOW_ZERO_FWD; 391 } else { 392 pRvlc->errorLogRvlc |= RVLC_ERROR_RVL_SUM_BIT_COUNTER_BELOW_ZERO_BWD; 393 } 394 value = -1; /* signalize an error in return value, because too many bits 395 was decoded */ 396 } 397 398 /* check max value of dpcm value */ 399 if (value > MAX_ALLOWED_DPCM_INDEX) { 400 if (direction == FWD) { 401 pRvlc->errorLogRvlc |= RVLC_ERROR_FORBIDDEN_CW_DETECTED_FWD; 402 } else { 403 pRvlc->errorLogRvlc |= RVLC_ERROR_FORBIDDEN_CW_DETECTED_BWD; 404 } 405 value = -1; /* signalize an error in return value, because a forbidden 406 cw was detected*/ 407 } 408 409 return value; /* return a dpcm value with offset +7 or an error status */ 410 } else { 411 treeNode = *( 412 pRvlCodeTree + 413 branchValue); /* update treeNode for further step in decoding tree */ 414 } 415 } 416 417 return -1; 418 } 419 420 /*--------------------------------------------------------------------------------------------- 421 function: rvlcDecodeForward 422 423 description: Decode RVL-coded codewords in forward direction. 424 ----------------------------------------------------------------------------------------------- 425 input: - pointer rvlc structure 426 - pointer channel info structure 427 - handle to FDK bitstream 428 ----------------------------------------------------------------------------------------------- 429 return: - 430 -------------------------------------------------------------------------------------------- 431 */ 432 433 static void rvlcDecodeForward(CErRvlcInfo *pRvlc, 434 CAacDecoderChannelInfo *pAacDecoderChannelInfo, 435 HANDLE_FDK_BITSTREAM bs) { 436 int band = 0; 437 int group = 0; 438 int bnds = 0; 439 440 SHORT dpcm; 441 442 SHORT factor = 443 pAacDecoderChannelInfo->pDynData->RawDataInfo.GlobalGain - SF_OFFSET; 444 SHORT position = -SF_OFFSET; 445 SHORT noisenrg = pAacDecoderChannelInfo->pDynData->RawDataInfo.GlobalGain - 446 SF_OFFSET - 90 - 256; 447 448 SHORT *pScfFwd = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd; 449 SHORT *pScfEsc = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfEsc; 450 UCHAR *pEscFwdCnt = &(pRvlc->numDecodedEscapeWordsFwd); 451 452 pRvlc->pRvlBitCnt_RVL = &(pRvlc->length_of_rvlc_sf_fwd); 453 pRvlc->pBitstrIndxRvl_RVL = &(pRvlc->bitstreamIndexRvlFwd); 454 455 *pEscFwdCnt = 0; 456 pRvlc->direction = FWD; 457 pRvlc->noise_used = 0; 458 pRvlc->sf_used = 0; 459 pRvlc->lastScf = 0; 460 pRvlc->lastNrg = 0; 461 pRvlc->lastIs = 0; 462 463 rvlcCheckIntensityCb(pRvlc, pAacDecoderChannelInfo); 464 465 /* main loop fwd long */ 466 for (group = 0; group < pRvlc->numWindowGroups; group++) { 467 for (band = 0; band < pRvlc->maxSfbTransmitted; band++) { 468 bnds = 16 * group + band; 469 470 switch (pAacDecoderChannelInfo->pDynData->aCodeBook[bnds]) { 471 case ZERO_HCB: 472 pScfFwd[bnds] = 0; 473 break; 474 475 case INTENSITY_HCB2: 476 case INTENSITY_HCB: 477 /* store dpcm_is_position */ 478 dpcm = decodeRVLCodeword(bs, pRvlc); 479 if (dpcm < 0) { 480 pRvlc->conceal_max = bnds; 481 return; 482 } 483 dpcm -= TABLE_OFFSET; 484 if ((dpcm == MIN_RVL) || (dpcm == MAX_RVL)) { 485 if (pRvlc->length_of_rvlc_escapes) { 486 pRvlc->conceal_max = bnds; 487 return; 488 } else { 489 if (dpcm == MIN_RVL) { 490 dpcm -= *pScfEsc++; 491 } else { 492 dpcm += *pScfEsc++; 493 } 494 (*pEscFwdCnt)++; 495 if (pRvlc->conceal_max_esc == CONCEAL_MAX_INIT) { 496 pRvlc->conceal_max_esc = bnds; 497 } 498 } 499 } 500 position += dpcm; 501 pScfFwd[bnds] = position; 502 pRvlc->lastIs = position; 503 break; 504 505 case NOISE_HCB: 506 if (pRvlc->noise_used == 0) { 507 pRvlc->noise_used = 1; 508 pRvlc->first_noise_band = bnds; 509 noisenrg += pRvlc->dpcm_noise_nrg; 510 pScfFwd[bnds] = 100 + noisenrg; 511 pRvlc->lastNrg = noisenrg; 512 } else { 513 dpcm = decodeRVLCodeword(bs, pRvlc); 514 if (dpcm < 0) { 515 pRvlc->conceal_max = bnds; 516 return; 517 } 518 dpcm -= TABLE_OFFSET; 519 if ((dpcm == MIN_RVL) || (dpcm == MAX_RVL)) { 520 if (pRvlc->length_of_rvlc_escapes) { 521 pRvlc->conceal_max = bnds; 522 return; 523 } else { 524 if (dpcm == MIN_RVL) { 525 dpcm -= *pScfEsc++; 526 } else { 527 dpcm += *pScfEsc++; 528 } 529 (*pEscFwdCnt)++; 530 if (pRvlc->conceal_max_esc == CONCEAL_MAX_INIT) { 531 pRvlc->conceal_max_esc = bnds; 532 } 533 } 534 } 535 noisenrg += dpcm; 536 pScfFwd[bnds] = 100 + noisenrg; 537 pRvlc->lastNrg = noisenrg; 538 } 539 pAacDecoderChannelInfo->data.aac.PnsData.pnsUsed[bnds] = 1; 540 break; 541 542 default: 543 pRvlc->sf_used = 1; 544 dpcm = decodeRVLCodeword(bs, pRvlc); 545 if (dpcm < 0) { 546 pRvlc->conceal_max = bnds; 547 return; 548 } 549 dpcm -= TABLE_OFFSET; 550 if ((dpcm == MIN_RVL) || (dpcm == MAX_RVL)) { 551 if (pRvlc->length_of_rvlc_escapes) { 552 pRvlc->conceal_max = bnds; 553 return; 554 } else { 555 if (dpcm == MIN_RVL) { 556 dpcm -= *pScfEsc++; 557 } else { 558 dpcm += *pScfEsc++; 559 } 560 (*pEscFwdCnt)++; 561 if (pRvlc->conceal_max_esc == CONCEAL_MAX_INIT) { 562 pRvlc->conceal_max_esc = bnds; 563 } 564 } 565 } 566 factor += dpcm; 567 pScfFwd[bnds] = factor; 568 pRvlc->lastScf = factor; 569 break; 570 } 571 } 572 } 573 574 /* postfetch fwd long */ 575 if (pRvlc->intensity_used) { 576 dpcm = decodeRVLCodeword(bs, pRvlc); /* dpcm_is_last_position */ 577 if (dpcm < 0) { 578 pRvlc->conceal_max = bnds; 579 return; 580 } 581 dpcm -= TABLE_OFFSET; 582 if ((dpcm == MIN_RVL) || (dpcm == MAX_RVL)) { 583 if (pRvlc->length_of_rvlc_escapes) { 584 pRvlc->conceal_max = bnds; 585 return; 586 } else { 587 if (dpcm == MIN_RVL) { 588 dpcm -= *pScfEsc++; 589 } else { 590 dpcm += *pScfEsc++; 591 } 592 (*pEscFwdCnt)++; 593 if (pRvlc->conceal_max_esc == CONCEAL_MAX_INIT) { 594 pRvlc->conceal_max_esc = bnds; 595 } 596 } 597 } 598 pRvlc->dpcm_is_last_position = dpcm; 599 } 600 } 601 602 /*--------------------------------------------------------------------------------------------- 603 function: rvlcDecodeBackward 604 605 description: Decode RVL-coded codewords in backward direction. 606 ----------------------------------------------------------------------------------------------- 607 input: - pointer rvlc structure 608 - pointer channel info structure 609 - handle FDK bitstream 610 ----------------------------------------------------------------------------------------------- 611 return: - 612 -------------------------------------------------------------------------------------------- 613 */ 614 615 static void rvlcDecodeBackward(CErRvlcInfo *pRvlc, 616 CAacDecoderChannelInfo *pAacDecoderChannelInfo, 617 HANDLE_FDK_BITSTREAM bs) { 618 SHORT band, group, dpcm, offset; 619 SHORT bnds = pRvlc->maxSfbTransmitted - 1; 620 621 SHORT factor = pRvlc->rev_global_gain - SF_OFFSET; 622 SHORT position = pRvlc->dpcm_is_last_position - SF_OFFSET; 623 SHORT noisenrg = pRvlc->rev_global_gain + pRvlc->dpcm_noise_last_position - 624 SF_OFFSET - 90 - 256; 625 626 SHORT *pScfBwd = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfBwd; 627 SHORT *pScfEsc = pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfEsc; 628 UCHAR *pEscEscCnt = &(pRvlc->numDecodedEscapeWordsEsc); 629 UCHAR *pEscBwdCnt = &(pRvlc->numDecodedEscapeWordsBwd); 630 631 pRvlc->pRvlBitCnt_RVL = &(pRvlc->length_of_rvlc_sf_bwd); 632 pRvlc->pBitstrIndxRvl_RVL = &(pRvlc->bitstreamIndexRvlBwd); 633 634 *pEscBwdCnt = 0; 635 pRvlc->direction = BWD; 636 pScfEsc += *pEscEscCnt - 1; /* set pScfEsc to last entry */ 637 pRvlc->firstScf = 0; 638 pRvlc->firstNrg = 0; 639 pRvlc->firstIs = 0; 640 641 /* prefetch long BWD */ 642 if (pRvlc->intensity_used) { 643 dpcm = decodeRVLCodeword(bs, pRvlc); /* dpcm_is_last_position */ 644 if (dpcm < 0) { 645 pRvlc->dpcm_is_last_position = 0; 646 pRvlc->conceal_min = bnds; 647 return; 648 } 649 dpcm -= TABLE_OFFSET; 650 if ((dpcm == MIN_RVL) || (dpcm == MAX_RVL)) { 651 if (pRvlc->length_of_rvlc_escapes) { 652 pRvlc->conceal_min = bnds; 653 return; 654 } else { 655 if (dpcm == MIN_RVL) { 656 dpcm -= *pScfEsc--; 657 } else { 658 dpcm += *pScfEsc--; 659 } 660 (*pEscBwdCnt)++; 661 if (pRvlc->conceal_min_esc == CONCEAL_MIN_INIT) { 662 pRvlc->conceal_min_esc = bnds; 663 } 664 } 665 } 666 pRvlc->dpcm_is_last_position = dpcm; 667 } 668 669 /* main loop long BWD */ 670 for (group = pRvlc->numWindowGroups - 1; group >= 0; group--) { 671 for (band = pRvlc->maxSfbTransmitted - 1; band >= 0; band--) { 672 bnds = 16 * group + band; 673 if ((band == 0) && (pRvlc->numWindowGroups != 1)) 674 offset = 16 - pRvlc->maxSfbTransmitted + 1; 675 else 676 offset = 1; 677 678 switch (pAacDecoderChannelInfo->pDynData->aCodeBook[bnds]) { 679 case ZERO_HCB: 680 pScfBwd[bnds] = 0; 681 break; 682 683 case INTENSITY_HCB2: 684 case INTENSITY_HCB: 685 /* store dpcm_is_position */ 686 dpcm = decodeRVLCodeword(bs, pRvlc); 687 if (dpcm < 0) { 688 pScfBwd[bnds] = position; 689 pRvlc->conceal_min = fMax(0, bnds - offset); 690 return; 691 } 692 dpcm -= TABLE_OFFSET; 693 if ((dpcm == MIN_RVL) || (dpcm == MAX_RVL)) { 694 if (pRvlc->length_of_rvlc_escapes) { 695 pScfBwd[bnds] = position; 696 pRvlc->conceal_min = fMax(0, bnds - offset); 697 return; 698 } else { 699 if (dpcm == MIN_RVL) { 700 dpcm -= *pScfEsc--; 701 } else { 702 dpcm += *pScfEsc--; 703 } 704 (*pEscBwdCnt)++; 705 if (pRvlc->conceal_min_esc == CONCEAL_MIN_INIT) { 706 pRvlc->conceal_min_esc = fMax(0, bnds - offset); 707 } 708 } 709 } 710 pScfBwd[bnds] = position; 711 position -= dpcm; 712 pRvlc->firstIs = position; 713 break; 714 715 case NOISE_HCB: 716 if (bnds == pRvlc->first_noise_band) { 717 pScfBwd[bnds] = 718 pRvlc->dpcm_noise_nrg + 719 pAacDecoderChannelInfo->pDynData->RawDataInfo.GlobalGain - 720 SF_OFFSET - 90 - 256; 721 pRvlc->firstNrg = pScfBwd[bnds]; 722 } else { 723 dpcm = decodeRVLCodeword(bs, pRvlc); 724 if (dpcm < 0) { 725 pScfBwd[bnds] = noisenrg; 726 pRvlc->conceal_min = fMax(0, bnds - offset); 727 return; 728 } 729 dpcm -= TABLE_OFFSET; 730 if ((dpcm == MIN_RVL) || (dpcm == MAX_RVL)) { 731 if (pRvlc->length_of_rvlc_escapes) { 732 pScfBwd[bnds] = noisenrg; 733 pRvlc->conceal_min = fMax(0, bnds - offset); 734 return; 735 } else { 736 if (dpcm == MIN_RVL) { 737 dpcm -= *pScfEsc--; 738 } else { 739 dpcm += *pScfEsc--; 740 } 741 (*pEscBwdCnt)++; 742 if (pRvlc->conceal_min_esc == CONCEAL_MIN_INIT) { 743 pRvlc->conceal_min_esc = fMax(0, bnds - offset); 744 } 745 } 746 } 747 pScfBwd[bnds] = noisenrg; 748 noisenrg -= dpcm; 749 pRvlc->firstNrg = noisenrg; 750 } 751 break; 752 753 default: 754 dpcm = decodeRVLCodeword(bs, pRvlc); 755 if (dpcm < 0) { 756 pScfBwd[bnds] = factor; 757 pRvlc->conceal_min = fMax(0, bnds - offset); 758 return; 759 } 760 dpcm -= TABLE_OFFSET; 761 if ((dpcm == MIN_RVL) || (dpcm == MAX_RVL)) { 762 if (pRvlc->length_of_rvlc_escapes) { 763 pScfBwd[bnds] = factor; 764 pRvlc->conceal_min = fMax(0, bnds - offset); 765 return; 766 } else { 767 if (dpcm == MIN_RVL) { 768 dpcm -= *pScfEsc--; 769 } else { 770 dpcm += *pScfEsc--; 771 } 772 (*pEscBwdCnt)++; 773 if (pRvlc->conceal_min_esc == CONCEAL_MIN_INIT) { 774 pRvlc->conceal_min_esc = fMax(0, bnds - offset); 775 } 776 } 777 } 778 pScfBwd[bnds] = factor; 779 factor -= dpcm; 780 pRvlc->firstScf = factor; 781 break; 782 } 783 } 784 } 785 } 786 787 /*--------------------------------------------------------------------------------------------- 788 function: rvlcFinalErrorDetection 789 790 description: Call RVLC concealment if error was detected in decoding 791 process 792 ----------------------------------------------------------------------------------------------- 793 input: - pointer rvlc structure 794 - pointer channel info structure 795 ----------------------------------------------------------------------------------------------- 796 return: - 797 -------------------------------------------------------------------------------------------- 798 */ 799 800 static void rvlcFinalErrorDetection( 801 CAacDecoderChannelInfo *pAacDecoderChannelInfo, 802 CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo) { 803 CErRvlcInfo *pRvlc = 804 &pAacDecoderChannelInfo->pComData->overlay.aac.erRvlcInfo; 805 UCHAR ErrorStatusComplete = 0; 806 UCHAR ErrorStatusLengthFwd = 0; 807 UCHAR ErrorStatusLengthBwd = 0; 808 UCHAR ErrorStatusLengthEscapes = 0; 809 UCHAR ErrorStatusFirstScf = 0; 810 UCHAR ErrorStatusLastScf = 0; 811 UCHAR ErrorStatusFirstNrg = 0; 812 UCHAR ErrorStatusLastNrg = 0; 813 UCHAR ErrorStatusFirstIs = 0; 814 UCHAR ErrorStatusLastIs = 0; 815 UCHAR ErrorStatusForbiddenCwFwd = 0; 816 UCHAR ErrorStatusForbiddenCwBwd = 0; 817 UCHAR ErrorStatusNumEscapesFwd = 0; 818 UCHAR ErrorStatusNumEscapesBwd = 0; 819 UCHAR ConcealStatus = 1; 820 UCHAR currentBlockType; /* short: 0, not short: 1*/ 821 822 pAacDecoderChannelInfo->pDynData->specificTo.aac.rvlcCurrentScaleFactorOK = 1; 823 824 /* invalid escape words, bit counter unequal zero, forbidden codeword detected 825 */ 826 if (pRvlc->errorLogRvlc & RVLC_ERROR_FORBIDDEN_CW_DETECTED_FWD) 827 ErrorStatusForbiddenCwFwd = 1; 828 829 if (pRvlc->errorLogRvlc & RVLC_ERROR_FORBIDDEN_CW_DETECTED_BWD) 830 ErrorStatusForbiddenCwBwd = 1; 831 832 /* bit counter forward unequal zero */ 833 if (pRvlc->length_of_rvlc_sf_fwd) ErrorStatusLengthFwd = 1; 834 835 /* bit counter backward unequal zero */ 836 if (pRvlc->length_of_rvlc_sf_bwd) ErrorStatusLengthBwd = 1; 837 838 /* bit counter escape sequences unequal zero */ 839 if (pRvlc->sf_escapes_present) 840 if (pRvlc->length_of_rvlc_escapes) ErrorStatusLengthEscapes = 1; 841 842 if (pRvlc->sf_used) { 843 /* first decoded scf does not match to global gain in backward direction */ 844 if (pRvlc->firstScf != 845 (pAacDecoderChannelInfo->pDynData->RawDataInfo.GlobalGain - SF_OFFSET)) 846 ErrorStatusFirstScf = 1; 847 848 /* last decoded scf does not match to rev global gain in forward direction 849 */ 850 if (pRvlc->lastScf != (pRvlc->rev_global_gain - SF_OFFSET)) 851 ErrorStatusLastScf = 1; 852 } 853 854 if (pRvlc->noise_used) { 855 /* first decoded nrg does not match to dpcm_noise_nrg in backward direction 856 */ 857 if (pRvlc->firstNrg != 858 (pAacDecoderChannelInfo->pDynData->RawDataInfo.GlobalGain + 859 pRvlc->dpcm_noise_nrg - SF_OFFSET - 90 - 256)) 860 ErrorStatusFirstNrg = 1; 861 862 /* last decoded nrg does not match to dpcm_noise_last_position in forward 863 * direction */ 864 if (pRvlc->lastNrg != 865 (pRvlc->rev_global_gain + pRvlc->dpcm_noise_last_position - SF_OFFSET - 866 90 - 256)) 867 ErrorStatusLastNrg = 1; 868 } 869 870 if (pRvlc->intensity_used) { 871 /* first decoded is position does not match in backward direction */ 872 if (pRvlc->firstIs != (-SF_OFFSET)) ErrorStatusFirstIs = 1; 873 874 /* last decoded is position does not match in forward direction */ 875 if (pRvlc->lastIs != (pRvlc->dpcm_is_last_position - SF_OFFSET)) 876 ErrorStatusLastIs = 1; 877 } 878 879 /* decoded escapes and used escapes in forward direction do not fit */ 880 if ((pRvlc->numDecodedEscapeWordsFwd != pRvlc->numDecodedEscapeWordsEsc) && 881 (pRvlc->conceal_max == CONCEAL_MAX_INIT)) { 882 ErrorStatusNumEscapesFwd = 1; 883 } 884 885 /* decoded escapes and used escapes in backward direction do not fit */ 886 if ((pRvlc->numDecodedEscapeWordsBwd != pRvlc->numDecodedEscapeWordsEsc) && 887 (pRvlc->conceal_min == CONCEAL_MIN_INIT)) { 888 ErrorStatusNumEscapesBwd = 1; 889 } 890 891 if (ErrorStatusLengthEscapes || 892 (((pRvlc->conceal_max == CONCEAL_MAX_INIT) && 893 (pRvlc->numDecodedEscapeWordsFwd != pRvlc->numDecodedEscapeWordsEsc) && 894 (ErrorStatusLastScf || ErrorStatusLastNrg || ErrorStatusLastIs)) 895 896 && 897 898 ((pRvlc->conceal_min == CONCEAL_MIN_INIT) && 899 (pRvlc->numDecodedEscapeWordsBwd != pRvlc->numDecodedEscapeWordsEsc) && 900 (ErrorStatusFirstScf || ErrorStatusFirstNrg || ErrorStatusFirstIs))) || 901 ((pRvlc->conceal_max == CONCEAL_MAX_INIT) && 902 ((pRvlc->rev_global_gain - SF_OFFSET - pRvlc->lastScf) < -15)) || 903 ((pRvlc->conceal_min == CONCEAL_MIN_INIT) && 904 ((pAacDecoderChannelInfo->pDynData->RawDataInfo.GlobalGain - SF_OFFSET - 905 pRvlc->firstScf) < -15))) { 906 if ((pRvlc->conceal_max == CONCEAL_MAX_INIT) || 907 (pRvlc->conceal_min == CONCEAL_MIN_INIT)) { 908 pRvlc->conceal_max = 0; 909 pRvlc->conceal_min = fMax( 910 0, (pRvlc->numWindowGroups - 1) * 16 + pRvlc->maxSfbTransmitted - 1); 911 } else { 912 pRvlc->conceal_max = fMin(pRvlc->conceal_max, pRvlc->conceal_max_esc); 913 pRvlc->conceal_min = fMax(pRvlc->conceal_min, pRvlc->conceal_min_esc); 914 } 915 } 916 917 ErrorStatusComplete = ErrorStatusLastScf || ErrorStatusFirstScf || 918 ErrorStatusLastNrg || ErrorStatusFirstNrg || 919 ErrorStatusLastIs || ErrorStatusFirstIs || 920 ErrorStatusForbiddenCwFwd || 921 ErrorStatusForbiddenCwBwd || ErrorStatusLengthFwd || 922 ErrorStatusLengthBwd || ErrorStatusLengthEscapes || 923 ErrorStatusNumEscapesFwd || ErrorStatusNumEscapesBwd; 924 925 currentBlockType = 926 (GetWindowSequence(&pAacDecoderChannelInfo->icsInfo) == BLOCK_SHORT) ? 0 927 : 1; 928 929 if (!ErrorStatusComplete) { 930 int band; 931 int group; 932 int bnds; 933 int lastSfbIndex; 934 935 lastSfbIndex = (pRvlc->numWindowGroups > 1) ? 16 : 64; 936 937 for (group = 0; group < pRvlc->numWindowGroups; group++) { 938 for (band = 0; band < pRvlc->maxSfbTransmitted; band++) { 939 bnds = 16 * group + band; 940 pAacDecoderChannelInfo->pDynData->aScaleFactor[bnds] = 941 pAacDecoderStaticChannelInfo->concealmentInfo 942 .aRvlcPreviousScaleFactor[bnds] = 943 pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfFwd[bnds]; 944 } 945 } 946 947 for (group = 0; group < pRvlc->numWindowGroups; group++) { 948 for (band = 0; band < pRvlc->maxSfbTransmitted; band++) { 949 bnds = 16 * group + band; 950 pAacDecoderStaticChannelInfo->concealmentInfo 951 .aRvlcPreviousCodebook[bnds] = 952 pAacDecoderChannelInfo->pDynData->aCodeBook[bnds]; 953 } 954 for (; band < lastSfbIndex; band++) { 955 bnds = 16 * group + band; 956 FDK_ASSERT(bnds >= 0 && bnds < RVLC_MAX_SFB); 957 pAacDecoderStaticChannelInfo->concealmentInfo 958 .aRvlcPreviousCodebook[bnds] = ZERO_HCB; 959 } 960 } 961 } else { 962 int band; 963 int group; 964 965 /* A single bit error was detected in decoding of dpcm values. It also could 966 be an error with more bits in decoding of escapes and dpcm values whereby 967 an illegal codeword followed not directly after the corrupted bits but 968 just after decoding some more (wrong) scalefactors. Use the smaller 969 scalefactor from forward decoding, backward decoding and previous frame. 970 */ 971 if (((pRvlc->conceal_min != CONCEAL_MIN_INIT) || 972 (pRvlc->conceal_max != CONCEAL_MAX_INIT)) && 973 (pRvlc->conceal_min <= pRvlc->conceal_max) && 974 (pAacDecoderStaticChannelInfo->concealmentInfo.rvlcPreviousBlockType == 975 currentBlockType) && 976 pAacDecoderStaticChannelInfo->concealmentInfo 977 .rvlcPreviousScaleFactorOK && 978 pRvlc->sf_concealment && ConcealStatus) { 979 BidirectionalEstimation_UseScfOfPrevFrameAsReference( 980 pAacDecoderChannelInfo, pAacDecoderStaticChannelInfo); 981 ConcealStatus = 0; 982 } 983 984 /* A single bit error was detected in decoding of dpcm values. It also could 985 be an error with more bits in decoding of escapes and dpcm values whereby 986 an illegal codeword followed not directly after the corrupted bits but 987 just after decoding some more (wrong) scalefactors. Use the smaller 988 scalefactor from forward and backward decoding. */ 989 if ((pRvlc->conceal_min <= pRvlc->conceal_max) && 990 ((pRvlc->conceal_min != CONCEAL_MIN_INIT) || 991 (pRvlc->conceal_max != CONCEAL_MAX_INIT)) && 992 !(pAacDecoderStaticChannelInfo->concealmentInfo 993 .rvlcPreviousScaleFactorOK && 994 pRvlc->sf_concealment && 995 (pAacDecoderStaticChannelInfo->concealmentInfo 996 .rvlcPreviousBlockType == currentBlockType)) && 997 ConcealStatus) { 998 BidirectionalEstimation_UseLowerScfOfCurrentFrame(pAacDecoderChannelInfo); 999 ConcealStatus = 0; 1000 } 1001 1002 /* No errors were detected in decoding of escapes and dpcm values however 1003 the first and last value of a group (is,nrg,sf) is incorrect */ 1004 if ((pRvlc->conceal_min <= pRvlc->conceal_max) && 1005 ((ErrorStatusLastScf && ErrorStatusFirstScf) || 1006 (ErrorStatusLastNrg && ErrorStatusFirstNrg) || 1007 (ErrorStatusLastIs && ErrorStatusFirstIs)) && 1008 !(ErrorStatusForbiddenCwFwd || ErrorStatusForbiddenCwBwd || 1009 ErrorStatusLengthEscapes) && 1010 ConcealStatus) { 1011 StatisticalEstimation(pAacDecoderChannelInfo); 1012 ConcealStatus = 0; 1013 } 1014 1015 /* A error with more bits in decoding of escapes and dpcm values was 1016 detected. Use the smaller scalefactor from forward decoding, backward 1017 decoding and previous frame. */ 1018 if ((pRvlc->conceal_min <= pRvlc->conceal_max) && 1019 pAacDecoderStaticChannelInfo->concealmentInfo 1020 .rvlcPreviousScaleFactorOK && 1021 pRvlc->sf_concealment && 1022 (pAacDecoderStaticChannelInfo->concealmentInfo.rvlcPreviousBlockType == 1023 currentBlockType) && 1024 ConcealStatus) { 1025 PredictiveInterpolation(pAacDecoderChannelInfo, 1026 pAacDecoderStaticChannelInfo); 1027 ConcealStatus = 0; 1028 } 1029 1030 /* Call frame concealment, because no better strategy was found. Setting the 1031 scalefactors to zero is done for debugging purposes */ 1032 if (ConcealStatus) { 1033 for (group = 0; group < pRvlc->numWindowGroups; group++) { 1034 for (band = 0; band < pRvlc->maxSfbTransmitted; band++) { 1035 pAacDecoderChannelInfo->pDynData->aScaleFactor[16 * group + band] = 0; 1036 } 1037 } 1038 pAacDecoderChannelInfo->pDynData->specificTo.aac 1039 .rvlcCurrentScaleFactorOK = 0; 1040 } 1041 } 1042 } 1043 1044 /*--------------------------------------------------------------------------------------------- 1045 function: CRvlc_Read 1046 1047 description: Read RVLC ESC1 data (side info) from bitstream. 1048 ----------------------------------------------------------------------------------------------- 1049 input: - pointer rvlc structure 1050 - pointer channel info structure 1051 - pointer bitstream structure 1052 ----------------------------------------------------------------------------------------------- 1053 return: - 1054 -------------------------------------------------------------------------------------------- 1055 */ 1056 1057 void CRvlc_Read(CAacDecoderChannelInfo *pAacDecoderChannelInfo, 1058 HANDLE_FDK_BITSTREAM bs) { 1059 CErRvlcInfo *pRvlc = 1060 &pAacDecoderChannelInfo->pComData->overlay.aac.erRvlcInfo; 1061 1062 int group, band; 1063 1064 /* RVLC long specific initialization Init part 1 of 2 */ 1065 pRvlc->numWindowGroups = GetWindowGroups(&pAacDecoderChannelInfo->icsInfo); 1066 pRvlc->maxSfbTransmitted = 1067 GetScaleFactorBandsTransmitted(&pAacDecoderChannelInfo->icsInfo); 1068 pRvlc->noise_used = 0; /* noise detection */ 1069 pRvlc->dpcm_noise_nrg = 0; /* only for debugging */ 1070 pRvlc->dpcm_noise_last_position = 0; /* only for debugging */ 1071 pRvlc->length_of_rvlc_escapes = 1072 -1; /* default value is used for error detection and concealment */ 1073 1074 /* read only error sensitivity class 1 data (ESC 1 - data) */ 1075 pRvlc->sf_concealment = FDKreadBits(bs, 1); /* #1 */ 1076 pRvlc->rev_global_gain = FDKreadBits(bs, 8); /* #2 */ 1077 1078 if (GetWindowSequence(&pAacDecoderChannelInfo->icsInfo) == BLOCK_SHORT) { 1079 pRvlc->length_of_rvlc_sf = FDKreadBits(bs, 11); /* #3 */ 1080 } else { 1081 pRvlc->length_of_rvlc_sf = FDKreadBits(bs, 9); /* #3 */ 1082 } 1083 1084 /* check if noise codebook is used */ 1085 for (group = 0; group < pRvlc->numWindowGroups; group++) { 1086 for (band = 0; band < pRvlc->maxSfbTransmitted; band++) { 1087 if (pAacDecoderChannelInfo->pDynData->aCodeBook[16 * group + band] == 1088 NOISE_HCB) { 1089 pRvlc->noise_used = 1; 1090 break; 1091 } 1092 } 1093 } 1094 1095 if (pRvlc->noise_used) 1096 pRvlc->dpcm_noise_nrg = FDKreadBits(bs, 9); /* #4 PNS */ 1097 1098 pRvlc->sf_escapes_present = FDKreadBits(bs, 1); /* #5 */ 1099 1100 if (pRvlc->sf_escapes_present) { 1101 pRvlc->length_of_rvlc_escapes = FDKreadBits(bs, 8); /* #6 */ 1102 } 1103 1104 if (pRvlc->noise_used) { 1105 pRvlc->dpcm_noise_last_position = FDKreadBits(bs, 9); /* #7 PNS */ 1106 pRvlc->length_of_rvlc_sf -= 9; 1107 } 1108 1109 pRvlc->length_of_rvlc_sf_fwd = pRvlc->length_of_rvlc_sf; 1110 pRvlc->length_of_rvlc_sf_bwd = pRvlc->length_of_rvlc_sf; 1111 } 1112 1113 /*--------------------------------------------------------------------------------------------- 1114 function: CRvlc_Decode 1115 1116 description: Decode rvlc data 1117 The function reads both the escape sequences and the 1118 scalefactors in forward and backward direction. If an error occured during 1119 decoding process which can not be concealed with the rvlc concealment frame 1120 concealment will be initiated. Then the element "rvlcCurrentScaleFactorOK" in 1121 the decoder channel info is set to 0 otherwise it is set to 1. 1122 ----------------------------------------------------------------------------------------------- 1123 input: - pointer rvlc structure 1124 - pointer channel info structure 1125 - pointer to persistent channel info structure 1126 - pointer bitstream structure 1127 ----------------------------------------------------------------------------------------------- 1128 return: ErrorStatus = AAC_DEC_OK 1129 -------------------------------------------------------------------------------------------- 1130 */ 1131 1132 void CRvlc_Decode(CAacDecoderChannelInfo *pAacDecoderChannelInfo, 1133 CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo, 1134 HANDLE_FDK_BITSTREAM bs) { 1135 CErRvlcInfo *pRvlc = 1136 &pAacDecoderChannelInfo->pComData->overlay.aac.erRvlcInfo; 1137 INT bitCntOffst; 1138 INT saveBitCnt; 1139 1140 rvlcInit(pRvlc, pAacDecoderChannelInfo, bs); 1141 1142 /* save bitstream position */ 1143 saveBitCnt = FDKgetBitCnt(bs); 1144 1145 if (pRvlc->sf_escapes_present) 1146 rvlcDecodeEscapes( 1147 pRvlc, pAacDecoderChannelInfo->pComData->overlay.aac.aRvlcScfEsc, bs); 1148 1149 rvlcDecodeForward(pRvlc, pAacDecoderChannelInfo, bs); 1150 rvlcDecodeBackward(pRvlc, pAacDecoderChannelInfo, bs); 1151 rvlcFinalErrorDetection(pAacDecoderChannelInfo, pAacDecoderStaticChannelInfo); 1152 1153 pAacDecoderChannelInfo->pDynData->specificTo.aac.rvlcIntensityUsed = 1154 pRvlc->intensity_used; 1155 pAacDecoderChannelInfo->data.aac.PnsData.PnsActive = pRvlc->noise_used; 1156 1157 /* restore bitstream position */ 1158 bitCntOffst = saveBitCnt - FDKgetBitCnt(bs); 1159 if (bitCntOffst) { 1160 FDKpushBiDirectional(bs, bitCntOffst); 1161 } 1162 } 1163 1164 void CRvlc_ElementCheck( 1165 CAacDecoderChannelInfo *pAacDecoderChannelInfo[], 1166 CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo[], 1167 const UINT flags, const INT elChannels) { 1168 int ch; 1169 1170 /* Required for MPS residuals. */ 1171 if (pAacDecoderStaticChannelInfo == NULL) { 1172 return; 1173 } 1174 1175 /* RVLC specific sanity checks */ 1176 if ((flags & AC_ER_RVLC) && (elChannels == 2)) { /* to be reviewed */ 1177 if (((pAacDecoderChannelInfo[0] 1178 ->pDynData->specificTo.aac.rvlcCurrentScaleFactorOK == 0) || 1179 (pAacDecoderChannelInfo[1] 1180 ->pDynData->specificTo.aac.rvlcCurrentScaleFactorOK == 0)) && 1181 pAacDecoderChannelInfo[0]->pComData->jointStereoData.MsMaskPresent) { 1182 pAacDecoderChannelInfo[0] 1183 ->pDynData->specificTo.aac.rvlcCurrentScaleFactorOK = 0; 1184 pAacDecoderChannelInfo[1] 1185 ->pDynData->specificTo.aac.rvlcCurrentScaleFactorOK = 0; 1186 } 1187 1188 if ((pAacDecoderChannelInfo[0] 1189 ->pDynData->specificTo.aac.rvlcCurrentScaleFactorOK == 0) && 1190 (pAacDecoderChannelInfo[1] 1191 ->pDynData->specificTo.aac.rvlcCurrentScaleFactorOK == 1) && 1192 (pAacDecoderChannelInfo[1] 1193 ->pDynData->specificTo.aac.rvlcIntensityUsed == 1)) { 1194 pAacDecoderChannelInfo[1] 1195 ->pDynData->specificTo.aac.rvlcCurrentScaleFactorOK = 0; 1196 } 1197 } 1198 1199 for (ch = 0; ch < elChannels; ch++) { 1200 pAacDecoderStaticChannelInfo[ch]->concealmentInfo.rvlcPreviousBlockType = 1201 (GetWindowSequence(&pAacDecoderChannelInfo[ch]->icsInfo) == BLOCK_SHORT) 1202 ? 0 1203 : 1; 1204 if (flags & AC_ER_RVLC) { 1205 pAacDecoderStaticChannelInfo[ch] 1206 ->concealmentInfo.rvlcPreviousScaleFactorOK = 1207 pAacDecoderChannelInfo[ch] 1208 ->pDynData->specificTo.aac.rvlcCurrentScaleFactorOK; 1209 } else { 1210 pAacDecoderStaticChannelInfo[ch] 1211 ->concealmentInfo.rvlcPreviousScaleFactorOK = 0; 1212 } 1213 } 1214 } 1215
