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Diffstat (limited to 'fdk-aac/libAACdec/src/stereo.cpp')
| -rw-r--r-- | fdk-aac/libAACdec/src/stereo.cpp | 1250 |
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diff --git a/fdk-aac/libAACdec/src/stereo.cpp b/fdk-aac/libAACdec/src/stereo.cpp new file mode 100644 index 0000000..eed826b --- /dev/null +++ b/fdk-aac/libAACdec/src/stereo.cpp @@ -0,0 +1,1250 @@ +/* ----------------------------------------------------------------------------- +Software License for The Fraunhofer FDK AAC Codec Library for Android + +© Copyright 1995 - 2018 Fraunhofer-Gesellschaft zur Förderung der angewandten +Forschung e.V. All rights reserved. + + 1. INTRODUCTION +The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software +that implements the MPEG Advanced Audio Coding ("AAC") encoding and decoding +scheme for digital audio. This FDK AAC Codec software is intended to be used on +a wide variety of Android devices. + +AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient +general perceptual audio codecs. AAC-ELD is considered the best-performing +full-bandwidth communications codec by independent studies and is widely +deployed. AAC has been standardized by ISO and IEC as part of the MPEG +specifications. + +Patent licenses for necessary patent claims for the FDK AAC Codec (including +those of Fraunhofer) may be obtained through Via Licensing +(www.vialicensing.com) or through the respective patent owners individually for +the purpose of encoding or decoding bit streams in products that are compliant +with the ISO/IEC MPEG audio standards. Please note that most manufacturers of +Android devices already license these patent claims through Via Licensing or +directly from the patent owners, and therefore FDK AAC Codec software may +already be covered under those patent licenses when it is used for those +licensed purposes only. + +Commercially-licensed AAC software libraries, including floating-point versions +with enhanced sound quality, are also available from Fraunhofer. Users are +encouraged to check the Fraunhofer website for additional applications +information and documentation. + +2. COPYRIGHT LICENSE + +Redistribution and use in source and binary forms, with or without modification, +are permitted without payment of copyright license fees provided that you +satisfy the following conditions: + +You must retain the complete text of this software license in redistributions of +the FDK AAC Codec or your modifications thereto in source code form. + +You must retain the complete text of this software license in the documentation +and/or other materials provided with redistributions of the FDK AAC Codec or +your modifications thereto in binary form. You must make available free of +charge copies of the complete source code of the FDK AAC Codec and your +modifications thereto to recipients of copies in binary form. + +The name of Fraunhofer may not be used to endorse or promote products derived +from this library without prior written permission. + +You may not charge copyright license fees for anyone to use, copy or distribute +the FDK AAC Codec software or your modifications thereto. + +Your modified versions of the FDK AAC Codec must carry prominent notices stating +that you changed the software and the date of any change. For modified versions +of the FDK AAC Codec, the term "Fraunhofer FDK AAC Codec Library for Android" +must be replaced by the term "Third-Party Modified Version of the Fraunhofer FDK +AAC Codec Library for Android." + +3. NO PATENT LICENSE + +NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without +limitation the patents of Fraunhofer, ARE GRANTED BY THIS SOFTWARE LICENSE. +Fraunhofer provides no warranty of patent non-infringement with respect to this +software. + +You may use this FDK AAC Codec software or modifications thereto only for +purposes that are authorized by appropriate patent licenses. + +4. DISCLAIMER + +This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright +holders and contributors "AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, +including but not limited to the implied warranties of merchantability and +fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR +CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, +or consequential damages, including but not limited to procurement of substitute +goods or services; loss of use, data, or profits, or business interruption, +however caused and on any theory of liability, whether in contract, strict +liability, or tort (including negligence), arising in any way out of the use of +this software, even if advised of the possibility of such damage. + +5. CONTACT INFORMATION + +Fraunhofer Institute for Integrated Circuits IIS +Attention: Audio and Multimedia Departments - FDK AAC LL +Am Wolfsmantel 33 +91058 Erlangen, Germany + +www.iis.fraunhofer.de/amm +amm-info@iis.fraunhofer.de +----------------------------------------------------------------------------- */ + +/**************************** AAC decoder library ****************************** + + Author(s): Josef Hoepfl + + Description: joint stereo processing + +*******************************************************************************/ + +#include "stereo.h" + +#include "aac_rom.h" +#include "FDK_bitstream.h" +#include "channelinfo.h" +#include "FDK_audio.h" + +enum { L = 0, R = 1 }; + +#include "block.h" + +int CJointStereo_Read(HANDLE_FDK_BITSTREAM bs, + CJointStereoData *pJointStereoData, + const int windowGroups, + const int scaleFactorBandsTransmitted, + const int max_sfb_ste_clear, + CJointStereoPersistentData *pJointStereoPersistentData, + CCplxPredictionData *cplxPredictionData, + int cplxPredictionActiv, int scaleFactorBandsTotal, + int windowSequence, const UINT flags) { + int group, band; + + pJointStereoData->MsMaskPresent = (UCHAR)FDKreadBits(bs, 2); + + FDKmemclear(pJointStereoData->MsUsed, + scaleFactorBandsTransmitted * sizeof(UCHAR)); + + pJointStereoData->cplx_pred_flag = 0; + if (cplxPredictionActiv) { + cplxPredictionData->pred_dir = 0; + cplxPredictionData->complex_coef = 0; + cplxPredictionData->use_prev_frame = 0; + cplxPredictionData->igf_pred_dir = 0; + } + + switch (pJointStereoData->MsMaskPresent) { + case 0: /* no M/S */ + /* all flags are already cleared */ + break; + + case 1: /* read ms_used */ + for (group = 0; group < windowGroups; group++) { + for (band = 0; band < scaleFactorBandsTransmitted; band++) { + pJointStereoData->MsUsed[band] |= (FDKreadBits(bs, 1) << group); + } + } + break; + + case 2: /* full spectrum M/S */ + for (band = 0; band < scaleFactorBandsTransmitted; band++) { + pJointStereoData->MsUsed[band] = 255; /* set all flags to 1 */ + } + break; + + case 3: + /* M/S coding is disabled, complex stereo prediction is enabled */ + if (flags & (AC_USAC | AC_RSVD50 | AC_RSV603DA)) { + if (cplxPredictionActiv) { /* 'if (stereoConfigIndex == 0)' */ + + pJointStereoData->cplx_pred_flag = 1; + + /* cplx_pred_data() cp. ISO/IEC FDIS 23003-3:2011(E) Table 26 */ + int cplx_pred_all = 0; /* local use only */ + cplx_pred_all = FDKreadBits(bs, 1); + + if (cplx_pred_all) { + for (group = 0; group < windowGroups; group++) { + UCHAR groupmask = ((UCHAR)1 << group); + for (band = 0; band < scaleFactorBandsTransmitted; band++) { + pJointStereoData->MsUsed[band] |= groupmask; + } + } + } else { + for (group = 0; group < windowGroups; group++) { + for (band = 0; band < scaleFactorBandsTransmitted; + band += SFB_PER_PRED_BAND) { + pJointStereoData->MsUsed[band] |= (FDKreadBits(bs, 1) << group); + if ((band + 1) < scaleFactorBandsTotal) { + pJointStereoData->MsUsed[band + 1] |= + (pJointStereoData->MsUsed[band] & ((UCHAR)1 << group)); + } + } + } + } + } else { + return -1; + } + } + break; + } + + if (cplxPredictionActiv) { + /* If all sfb are MS-ed then no complex prediction */ + if (pJointStereoData->MsMaskPresent == 3) { + if (pJointStereoData->cplx_pred_flag) { + int delta_code_time = 0; + + /* set pointer to Huffman codebooks */ + const CodeBookDescription *hcb = &AACcodeBookDescriptionTable[BOOKSCL]; + /* set predictors to zero in case of a transition from long to short + * window sequences and vice versa */ + if (((windowSequence == BLOCK_SHORT) && + (pJointStereoPersistentData->winSeqPrev != BLOCK_SHORT)) || + ((pJointStereoPersistentData->winSeqPrev == BLOCK_SHORT) && + (windowSequence != BLOCK_SHORT))) { + FDKmemclear(pJointStereoPersistentData->alpha_q_re_prev, + JointStereoMaximumGroups * JointStereoMaximumBands * + sizeof(SHORT)); + FDKmemclear(pJointStereoPersistentData->alpha_q_im_prev, + JointStereoMaximumGroups * JointStereoMaximumBands * + sizeof(SHORT)); + } + { + FDKmemclear(cplxPredictionData->alpha_q_re, + JointStereoMaximumGroups * JointStereoMaximumBands * + sizeof(SHORT)); + FDKmemclear(cplxPredictionData->alpha_q_im, + JointStereoMaximumGroups * JointStereoMaximumBands * + sizeof(SHORT)); + } + + /* 0 = mid->side prediction, 1 = side->mid prediction */ + cplxPredictionData->pred_dir = FDKreadBits(bs, 1); + cplxPredictionData->complex_coef = FDKreadBits(bs, 1); + + if (cplxPredictionData->complex_coef) { + if (flags & AC_INDEP) { + cplxPredictionData->use_prev_frame = 0; + } else { + cplxPredictionData->use_prev_frame = FDKreadBits(bs, 1); + } + } + + if (flags & AC_INDEP) { + delta_code_time = 0; + } else { + delta_code_time = FDKreadBits(bs, 1); + } + + { + int last_alpha_q_re = 0, last_alpha_q_im = 0; + + for (group = 0; group < windowGroups; group++) { + for (band = 0; band < scaleFactorBandsTransmitted; + band += SFB_PER_PRED_BAND) { + if (delta_code_time == 1) { + if (group > 0) { + last_alpha_q_re = + cplxPredictionData->alpha_q_re[group - 1][band]; + last_alpha_q_im = + cplxPredictionData->alpha_q_im[group - 1][band]; + } else if ((windowSequence == BLOCK_SHORT) && + (pJointStereoPersistentData->winSeqPrev == + BLOCK_SHORT)) { + /* Included for error-robustness */ + if (pJointStereoPersistentData->winGroupsPrev == 0) return -1; + + last_alpha_q_re = + pJointStereoPersistentData->alpha_q_re_prev + [pJointStereoPersistentData->winGroupsPrev - 1][band]; + last_alpha_q_im = + pJointStereoPersistentData->alpha_q_im_prev + [pJointStereoPersistentData->winGroupsPrev - 1][band]; + } else { + last_alpha_q_re = + pJointStereoPersistentData->alpha_q_re_prev[group][band]; + last_alpha_q_im = + pJointStereoPersistentData->alpha_q_im_prev[group][band]; + } + + } else { + if (band > 0) { + last_alpha_q_re = + cplxPredictionData->alpha_q_re[group][band - 1]; + last_alpha_q_im = + cplxPredictionData->alpha_q_im[group][band - 1]; + } else { + last_alpha_q_re = 0; + last_alpha_q_im = 0; + } + + } /* if (delta_code_time == 1) */ + + if (pJointStereoData->MsUsed[band] & ((UCHAR)1 << group)) { + int dpcm_alpha_re, dpcm_alpha_im; + + dpcm_alpha_re = CBlock_DecodeHuffmanWord(bs, hcb); + dpcm_alpha_re -= 60; + dpcm_alpha_re *= -1; + + cplxPredictionData->alpha_q_re[group][band] = + dpcm_alpha_re + last_alpha_q_re; + + if (cplxPredictionData->complex_coef) { + dpcm_alpha_im = CBlock_DecodeHuffmanWord(bs, hcb); + dpcm_alpha_im -= 60; + dpcm_alpha_im *= -1; + + cplxPredictionData->alpha_q_im[group][band] = + dpcm_alpha_im + last_alpha_q_im; + } else { + cplxPredictionData->alpha_q_im[group][band] = 0; + } + + } else { + cplxPredictionData->alpha_q_re[group][band] = 0; + cplxPredictionData->alpha_q_im[group][band] = 0; + } /* if (pJointStereoData->MsUsed[band] & ((UCHAR)1 << group)) */ + + if ((band + 1) < + scaleFactorBandsTransmitted) { /* <= this should be the + correct way (cp. + ISO_IEC_FDIS_23003-0(E) */ + /* 7.7.2.3.2 Decoding of prediction coefficients) */ + cplxPredictionData->alpha_q_re[group][band + 1] = + cplxPredictionData->alpha_q_re[group][band]; + cplxPredictionData->alpha_q_im[group][band + 1] = + cplxPredictionData->alpha_q_im[group][band]; + } /* if ((band+1)<scaleFactorBandsTotal) */ + + pJointStereoPersistentData->alpha_q_re_prev[group][band] = + cplxPredictionData->alpha_q_re[group][band]; + pJointStereoPersistentData->alpha_q_im_prev[group][band] = + cplxPredictionData->alpha_q_im[group][band]; + } + + for (band = scaleFactorBandsTransmitted; band < max_sfb_ste_clear; + band++) { + cplxPredictionData->alpha_q_re[group][band] = 0; + cplxPredictionData->alpha_q_im[group][band] = 0; + pJointStereoPersistentData->alpha_q_re_prev[group][band] = 0; + pJointStereoPersistentData->alpha_q_im_prev[group][band] = 0; + } + } + } + } + } else { + for (group = 0; group < windowGroups; group++) { + for (band = 0; band < max_sfb_ste_clear; band++) { + pJointStereoPersistentData->alpha_q_re_prev[group][band] = 0; + pJointStereoPersistentData->alpha_q_im_prev[group][band] = 0; + } + } + } + + pJointStereoPersistentData->winGroupsPrev = windowGroups; + } + + return 0; +} + +static void CJointStereo_filterAndAdd( + FIXP_DBL *in, int len, int windowLen, const FIXP_FILT *coeff, FIXP_DBL *out, + UCHAR isCurrent /* output values with even index get a + positve addon (=1) or a negative addon + (=0) */ +) { + int i, j; + + int indices_1[] = {2, 1, 0, 1, 2, 3}; + int indices_2[] = {1, 0, 0, 2, 3, 4}; + int indices_3[] = {0, 0, 1, 3, 4, 5}; + + int subtr_1[] = {6, 5, 4, 2, 1, 1}; + int subtr_2[] = {5, 4, 3, 1, 1, 2}; + int subtr_3[] = {4, 3, 2, 1, 2, 3}; + + if (isCurrent == 1) { + /* exploit the symmetry of the table: coeff[6] = - coeff[0], + coeff[5] = - coeff[1], + coeff[4] = - coeff[2], + coeff[3] = 0 + */ + + for (i = 0; i < 3; i++) { + out[0] -= (FIXP_DBL)fMultDiv2(coeff[i], in[indices_1[i]]) >> SR_FNA_OUT; + out[0] += + (FIXP_DBL)fMultDiv2(coeff[i], in[indices_1[5 - i]]) >> SR_FNA_OUT; + } + + for (i = 0; i < 3; i++) { + out[1] -= (FIXP_DBL)fMultDiv2(coeff[i], in[indices_2[i]]) >> SR_FNA_OUT; + out[1] += + (FIXP_DBL)fMultDiv2(coeff[i], in[indices_2[5 - i]]) >> SR_FNA_OUT; + } + + for (i = 0; i < 3; i++) { + out[2] -= (FIXP_DBL)fMultDiv2(coeff[i], in[indices_3[i]]) >> SR_FNA_OUT; + out[2] += + (FIXP_DBL)fMultDiv2(coeff[i], in[indices_3[5 - i]]) >> SR_FNA_OUT; + } + + for (j = 3; j < (len - 3); j++) { + for (i = 0; i < 3; i++) { + out[j] -= (FIXP_DBL)fMultDiv2(coeff[i], in[j - 3 + i]) >> SR_FNA_OUT; + out[j] += (FIXP_DBL)fMultDiv2(coeff[i], in[j + 3 - i]) >> SR_FNA_OUT; + } + } + + for (i = 0; i < 3; i++) { + out[len - 3] -= + (FIXP_DBL)fMultDiv2(coeff[i], in[len - subtr_1[i]]) >> SR_FNA_OUT; + out[len - 3] += + (FIXP_DBL)fMultDiv2(coeff[i], in[len - subtr_1[5 - i]]) >> SR_FNA_OUT; + } + + for (i = 0; i < 3; i++) { + out[len - 2] -= + (FIXP_DBL)fMultDiv2(coeff[i], in[len - subtr_2[i]]) >> SR_FNA_OUT; + out[len - 2] += + (FIXP_DBL)fMultDiv2(coeff[i], in[len - subtr_2[5 - i]]) >> SR_FNA_OUT; + } + + for (i = 0; i < 3; i++) { + out[len - 1] -= + (FIXP_DBL)fMultDiv2(coeff[i], in[len - subtr_3[i]]) >> SR_FNA_OUT; + out[len - 1] += + (FIXP_DBL)fMultDiv2(coeff[i], in[len - subtr_3[5 - i]]) >> SR_FNA_OUT; + } + + } else { + /* exploit the symmetry of the table: coeff[6] = coeff[0], + coeff[5] = coeff[1], + coeff[4] = coeff[2] + */ + + for (i = 0; i < 3; i++) { + out[0] -= (FIXP_DBL)fMultDiv2(coeff[i], in[indices_1[i]] >> SR_FNA_OUT); + out[0] -= + (FIXP_DBL)fMultDiv2(coeff[i], in[indices_1[5 - i]] >> SR_FNA_OUT); + } + out[0] -= (FIXP_DBL)fMultDiv2(coeff[3], in[0] >> SR_FNA_OUT); + + for (i = 0; i < 3; i++) { + out[1] += (FIXP_DBL)fMultDiv2(coeff[i], in[indices_2[i]] >> SR_FNA_OUT); + out[1] += + (FIXP_DBL)fMultDiv2(coeff[i], in[indices_2[5 - i]] >> SR_FNA_OUT); + } + out[1] += (FIXP_DBL)fMultDiv2(coeff[3], in[1] >> SR_FNA_OUT); + + for (i = 0; i < 3; i++) { + out[2] -= (FIXP_DBL)fMultDiv2(coeff[i], in[indices_3[i]] >> SR_FNA_OUT); + out[2] -= + (FIXP_DBL)fMultDiv2(coeff[i], in[indices_3[5 - i]] >> SR_FNA_OUT); + } + out[2] -= (FIXP_DBL)fMultDiv2(coeff[3], in[2] >> SR_FNA_OUT); + + for (j = 3; j < (len - 4); j++) { + for (i = 0; i < 3; i++) { + out[j] += (FIXP_DBL)fMultDiv2(coeff[i], in[j - 3 + i] >> SR_FNA_OUT); + out[j] += (FIXP_DBL)fMultDiv2(coeff[i], in[j + 3 - i] >> SR_FNA_OUT); + } + out[j] += (FIXP_DBL)fMultDiv2(coeff[3], in[j] >> SR_FNA_OUT); + + j++; + + for (i = 0; i < 3; i++) { + out[j] -= (FIXP_DBL)fMultDiv2(coeff[i], in[j - 3 + i] >> SR_FNA_OUT); + out[j] -= (FIXP_DBL)fMultDiv2(coeff[i], in[j + 3 - i] >> SR_FNA_OUT); + } + out[j] -= (FIXP_DBL)fMultDiv2(coeff[3], in[j] >> SR_FNA_OUT); + } + + for (i = 0; i < 3; i++) { + out[len - 3] += + (FIXP_DBL)fMultDiv2(coeff[i], in[len - subtr_1[i]] >> SR_FNA_OUT); + out[len - 3] += + (FIXP_DBL)fMultDiv2(coeff[i], in[len - subtr_1[5 - i]] >> SR_FNA_OUT); + } + out[len - 3] += (FIXP_DBL)fMultDiv2(coeff[3], in[len - 3] >> SR_FNA_OUT); + + for (i = 0; i < 3; i++) { + out[len - 2] -= + (FIXP_DBL)fMultDiv2(coeff[i], in[len - subtr_2[i]] >> SR_FNA_OUT); + out[len - 2] -= + (FIXP_DBL)fMultDiv2(coeff[i], in[len - subtr_2[5 - i]] >> SR_FNA_OUT); + } + out[len - 2] -= (FIXP_DBL)fMultDiv2(coeff[3], in[len - 2] >> SR_FNA_OUT); + + for (i = 0; i < 3; i++) { + out[len - 1] += + (FIXP_DBL)fMultDiv2(coeff[i], in[len - subtr_3[i]] >> SR_FNA_OUT); + out[len - 1] += + (FIXP_DBL)fMultDiv2(coeff[i], in[len - subtr_3[5 - i]] >> SR_FNA_OUT); + } + out[len - 1] += (FIXP_DBL)fMultDiv2(coeff[3], in[len - 1] >> SR_FNA_OUT); + } +} + +static inline void CJointStereo_GenerateMSOutput(FIXP_DBL *pSpecLCurrBand, + FIXP_DBL *pSpecRCurrBand, + UINT leftScale, + UINT rightScale, + UINT nSfbBands) { + unsigned int i; + + FIXP_DBL leftCoefficient0; + FIXP_DBL leftCoefficient1; + FIXP_DBL leftCoefficient2; + FIXP_DBL leftCoefficient3; + + FIXP_DBL rightCoefficient0; + FIXP_DBL rightCoefficient1; + FIXP_DBL rightCoefficient2; + FIXP_DBL rightCoefficient3; + + for (i = nSfbBands; i > 0; i -= 4) { + leftCoefficient0 = pSpecLCurrBand[i - 4]; + leftCoefficient1 = pSpecLCurrBand[i - 3]; + leftCoefficient2 = pSpecLCurrBand[i - 2]; + leftCoefficient3 = pSpecLCurrBand[i - 1]; + + rightCoefficient0 = pSpecRCurrBand[i - 4]; + rightCoefficient1 = pSpecRCurrBand[i - 3]; + rightCoefficient2 = pSpecRCurrBand[i - 2]; + rightCoefficient3 = pSpecRCurrBand[i - 1]; + + /* MS output generation */ + leftCoefficient0 >>= leftScale; + leftCoefficient1 >>= leftScale; + leftCoefficient2 >>= leftScale; + leftCoefficient3 >>= leftScale; + + rightCoefficient0 >>= rightScale; + rightCoefficient1 >>= rightScale; + rightCoefficient2 >>= rightScale; + rightCoefficient3 >>= rightScale; + + pSpecLCurrBand[i - 4] = leftCoefficient0 + rightCoefficient0; + pSpecLCurrBand[i - 3] = leftCoefficient1 + rightCoefficient1; + pSpecLCurrBand[i - 2] = leftCoefficient2 + rightCoefficient2; + pSpecLCurrBand[i - 1] = leftCoefficient3 + rightCoefficient3; + + pSpecRCurrBand[i - 4] = leftCoefficient0 - rightCoefficient0; + pSpecRCurrBand[i - 3] = leftCoefficient1 - rightCoefficient1; + pSpecRCurrBand[i - 2] = leftCoefficient2 - rightCoefficient2; + pSpecRCurrBand[i - 1] = leftCoefficient3 - rightCoefficient3; + } +} + +void CJointStereo_ApplyMS( + CAacDecoderChannelInfo *pAacDecoderChannelInfo[2], + CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo[2], + FIXP_DBL *spectrumL, FIXP_DBL *spectrumR, SHORT *SFBleftScale, + SHORT *SFBrightScale, SHORT *specScaleL, SHORT *specScaleR, + const SHORT *pScaleFactorBandOffsets, const UCHAR *pWindowGroupLength, + const int windowGroups, const int max_sfb_ste_outside, + const int scaleFactorBandsTransmittedL, + const int scaleFactorBandsTransmittedR, FIXP_DBL *store_dmx_re_prev, + SHORT *store_dmx_re_prev_e, const int mainband_flag) { + int window, group, band; + UCHAR groupMask; + CJointStereoData *pJointStereoData = + &pAacDecoderChannelInfo[L]->pComData->jointStereoData; + CCplxPredictionData *cplxPredictionData = + pAacDecoderChannelInfo[L]->pComStaticData->cplxPredictionData; + + int max_sfb_ste = + fMax(scaleFactorBandsTransmittedL, scaleFactorBandsTransmittedR); + int min_sfb_ste = + fMin(scaleFactorBandsTransmittedL, scaleFactorBandsTransmittedR); + int scaleFactorBandsTransmitted = min_sfb_ste; + + if (pJointStereoData->cplx_pred_flag) { + int windowLen, groupwin, frameMaxScale; + CJointStereoPersistentData *pJointStereoPersistentData = + &pAacDecoderStaticChannelInfo[L] + ->pCpeStaticData->jointStereoPersistentData; + FIXP_DBL *const staticSpectralCoeffsL = + pAacDecoderStaticChannelInfo[L] + ->pCpeStaticData->jointStereoPersistentData.spectralCoeffs[L]; + FIXP_DBL *const staticSpectralCoeffsR = + pAacDecoderStaticChannelInfo[L] + ->pCpeStaticData->jointStereoPersistentData.spectralCoeffs[R]; + SHORT *const staticSpecScaleL = + pAacDecoderStaticChannelInfo[L] + ->pCpeStaticData->jointStereoPersistentData.specScale[L]; + SHORT *const staticSpecScaleR = + pAacDecoderStaticChannelInfo[L] + ->pCpeStaticData->jointStereoPersistentData.specScale[R]; + + FIXP_DBL *dmx_re = + pAacDecoderStaticChannelInfo[L] + ->pCpeStaticData->jointStereoPersistentData.scratchBuffer; + FIXP_DBL *dmx_re_prev = + pAacDecoderStaticChannelInfo[L] + ->pCpeStaticData->jointStereoPersistentData.scratchBuffer + + 1024; + + /* When MS is applied over the main band this value gets computed. Otherwise + * (for the tiles) it uses the assigned value */ + SHORT dmx_re_prev_e = *store_dmx_re_prev_e; + + const FIXP_FILT *pCoeff; + const FIXP_FILT *pCoeffPrev; + int coeffPointerOffset; + + int previousShape = (int)pJointStereoPersistentData->winShapePrev; + int currentShape = (int)pAacDecoderChannelInfo[L]->icsInfo.WindowShape; + + /* complex stereo prediction */ + + /* 0. preparations */ + + /* 0.0. get scratch buffer for downmix MDST */ + C_AALLOC_SCRATCH_START(dmx_im, FIXP_DBL, 1024); + + /* 0.1. window lengths */ + + /* get length of short window for current configuration */ + windowLen = + pAacDecoderChannelInfo[L]->granuleLength; /* framelength 768 => 96, + framelength 1024 => 128 */ + + /* if this is no short-block set length for long-block */ + if (pAacDecoderChannelInfo[L]->icsInfo.WindowSequence != BLOCK_SHORT) { + windowLen *= 8; + } + + /* 0.2. set pointer to filter-coefficients for MDST excitation including + * previous frame portions */ + /* cp. ISO/IEC FDIS 23003-3:2011(E) table 125 */ + + /* set pointer to default-position */ + pCoeffPrev = mdst_filt_coef_prev[previousShape]; + + if (cplxPredictionData->complex_coef == 1) { + switch (pAacDecoderChannelInfo[L] + ->icsInfo.WindowSequence) { /* current window sequence */ + case BLOCK_SHORT: + case BLOCK_LONG: + pCoeffPrev = mdst_filt_coef_prev[previousShape]; + break; + + case BLOCK_START: + if ((pJointStereoPersistentData->winSeqPrev == BLOCK_SHORT) || + (pJointStereoPersistentData->winSeqPrev == BLOCK_START)) { + /* a stop-start-sequence can only follow on an eight-short-sequence + * or a start-sequence */ + pCoeffPrev = mdst_filt_coef_prev[2 + previousShape]; + } else { + pCoeffPrev = mdst_filt_coef_prev[previousShape]; + } + break; + + case BLOCK_STOP: + pCoeffPrev = mdst_filt_coef_prev[2 + previousShape]; + break; + + default: + pCoeffPrev = mdst_filt_coef_prev[previousShape]; + break; + } + } + + /* 0.3. set pointer to filter-coefficients for MDST excitation */ + + /* define offset of pointer to filter-coefficients for MDST exitation + * employing only the current frame */ + if ((previousShape == SHAPE_SINE) && (currentShape == SHAPE_SINE)) { + coeffPointerOffset = 0; + } else if ((previousShape == SHAPE_SINE) && (currentShape == SHAPE_KBD)) { + coeffPointerOffset = 2; + } else if ((previousShape == SHAPE_KBD) && (currentShape == SHAPE_KBD)) { + coeffPointerOffset = 1; + } else /* if ( (previousShape == SHAPE_KBD) && (currentShape == SHAPE_SINE) + ) */ + { + coeffPointerOffset = 3; + } + + /* set pointer to filter-coefficient table cp. ISO/IEC FDIS 23003-3:2011(E) + * table 124 */ + switch (pAacDecoderChannelInfo[L] + ->icsInfo.WindowSequence) { /* current window sequence */ + case BLOCK_SHORT: + case BLOCK_LONG: + pCoeff = mdst_filt_coef_curr[coeffPointerOffset]; + break; + + case BLOCK_START: + if ((pJointStereoPersistentData->winSeqPrev == BLOCK_SHORT) || + (pJointStereoPersistentData->winSeqPrev == BLOCK_START)) { + /* a stop-start-sequence can only follow on an eight-short-sequence or + * a start-sequence */ + pCoeff = mdst_filt_coef_curr[12 + coeffPointerOffset]; + } else { + pCoeff = mdst_filt_coef_curr[4 + coeffPointerOffset]; + } + break; + + case BLOCK_STOP: + pCoeff = mdst_filt_coef_curr[8 + coeffPointerOffset]; + break; + + default: + pCoeff = mdst_filt_coef_curr[coeffPointerOffset]; + } + + /* 0.4. find maximum common (l/r) band-scaling-factor for whole sequence + * (all windows) */ + frameMaxScale = 0; + for (window = 0, group = 0; group < windowGroups; group++) { + for (groupwin = 0; groupwin < pWindowGroupLength[group]; + groupwin++, window++) { + SHORT *leftScale = &SFBleftScale[window * 16]; + SHORT *rightScale = &SFBrightScale[window * 16]; + int windowMaxScale = 0; + + /* find maximum scaling factor of all bands in this window */ + for (band = 0; band < min_sfb_ste; band++) { + int lScale = leftScale[band]; + int rScale = rightScale[band]; + int commonScale = ((lScale > rScale) ? lScale : rScale); + windowMaxScale = + (windowMaxScale < commonScale) ? commonScale : windowMaxScale; + } + if (scaleFactorBandsTransmittedL > + min_sfb_ste) { /* i.e. scaleFactorBandsTransmittedL == max_sfb_ste + */ + for (; band < max_sfb_ste; band++) { + int lScale = leftScale[band]; + windowMaxScale = + (windowMaxScale < lScale) ? lScale : windowMaxScale; + } + } else { + if (scaleFactorBandsTransmittedR > + min_sfb_ste) { /* i.e. scaleFactorBandsTransmittedR == max_sfb_ste + */ + for (; band < max_sfb_ste; band++) { + int rScale = rightScale[band]; + windowMaxScale = + (windowMaxScale < rScale) ? rScale : windowMaxScale; + } + } + } + + /* find maximum common SF of all windows */ + frameMaxScale = + (frameMaxScale < windowMaxScale) ? windowMaxScale : frameMaxScale; + } + } + + /* add some headroom for overflow protection during filter and add operation + */ + frameMaxScale += 2; + + /* process on window-basis (i.e. iterate over all groups and corresponding + * windows) */ + for (window = 0, group = 0; group < windowGroups; group++) { + groupMask = 1 << group; + + for (groupwin = 0; groupwin < pWindowGroupLength[group]; + groupwin++, window++) { + /* initialize the MDST with zeros */ + FDKmemclear(&dmx_im[windowLen * window], windowLen * sizeof(FIXP_DBL)); + + /* 1. calculate the previous downmix MDCT. We do this once just for the + * Main band. */ + if (cplxPredictionData->complex_coef == 1) { + if ((cplxPredictionData->use_prev_frame == 1) && (mainband_flag)) { + /* if this is a long-block or the first window of a short-block + calculate the downmix MDCT of the previous frame. + use_prev_frame is assumed not to change during a frame! + */ + + /* first determine shiftfactors to scale left and right channel */ + if ((pAacDecoderChannelInfo[L]->icsInfo.WindowSequence != + BLOCK_SHORT) || + (window == 0)) { + int index_offset = 0; + int srLeftChan = 0; + int srRightChan = 0; + if (pAacDecoderChannelInfo[L]->icsInfo.WindowSequence == + BLOCK_SHORT) { + /* use the last window of the previous frame for MDCT + * calculation if this is a short-block. */ + index_offset = windowLen * 7; + if (staticSpecScaleL[7] > staticSpecScaleR[7]) { + srRightChan = staticSpecScaleL[7] - staticSpecScaleR[7]; + dmx_re_prev_e = staticSpecScaleL[7]; + } else { + srLeftChan = staticSpecScaleR[7] - staticSpecScaleL[7]; + dmx_re_prev_e = staticSpecScaleR[7]; + } + } else { + if (staticSpecScaleL[0] > staticSpecScaleR[0]) { + srRightChan = staticSpecScaleL[0] - staticSpecScaleR[0]; + dmx_re_prev_e = staticSpecScaleL[0]; + } else { + srLeftChan = staticSpecScaleR[0] - staticSpecScaleL[0]; + dmx_re_prev_e = staticSpecScaleR[0]; + } + } + + /* now scale channels and determine downmix MDCT of previous frame + */ + if (pAacDecoderStaticChannelInfo[L] + ->pCpeStaticData->jointStereoPersistentData + .clearSpectralCoeffs == 1) { + FDKmemclear(dmx_re_prev, windowLen * sizeof(FIXP_DBL)); + dmx_re_prev_e = 0; + } else { + if (cplxPredictionData->pred_dir == 0) { + for (int i = 0; i < windowLen; i++) { + dmx_re_prev[i] = + ((staticSpectralCoeffsL[index_offset + i] >> + srLeftChan) + + (staticSpectralCoeffsR[index_offset + i] >> + srRightChan)) >> + 1; + } + } else { + for (int i = 0; i < windowLen; i++) { + dmx_re_prev[i] = + ((staticSpectralCoeffsL[index_offset + i] >> + srLeftChan) - + (staticSpectralCoeffsR[index_offset + i] >> + srRightChan)) >> + 1; + } + } + } + + /* In case that we use INF we have to preserve the state of the + "dmx_re_prev" (original or computed). This is necessary because we + have to apply MS over the separate IGF tiles. */ + FDKmemcpy(store_dmx_re_prev, &dmx_re_prev[0], + windowLen * sizeof(FIXP_DBL)); + + /* Particular exponent of the computed/original "dmx_re_prev" must + * be kept for the tile MS calculations if necessary.*/ + *store_dmx_re_prev_e = dmx_re_prev_e; + + } /* if ( (pAacDecoderChannelInfo[L]->icsInfo.WindowSequence != + BLOCK_SHORT) || (window == 0) ) */ + + } /* if ( pJointStereoData->use_prev_frame == 1 ) */ + + } /* if ( pJointStereoData->complex_coef == 1 ) */ + + /* 2. calculate downmix MDCT of current frame */ + + /* set pointer to scale-factor-bands of current window */ + SHORT *leftScale = &SFBleftScale[window * 16]; + SHORT *rightScale = &SFBrightScale[window * 16]; + + specScaleL[window] = specScaleR[window] = frameMaxScale; + + /* adapt scaling-factors to previous frame */ + if (cplxPredictionData->use_prev_frame == 1) { + if (window == 0) { + if (dmx_re_prev_e < frameMaxScale) { + if (mainband_flag == 0) { + scaleValues(dmx_re_prev, store_dmx_re_prev, windowLen, + -(frameMaxScale - dmx_re_prev_e)); + } else { + for (int i = 0; i < windowLen; i++) { + dmx_re_prev[i] >>= (frameMaxScale - dmx_re_prev_e); + } + } + } else { + if (mainband_flag == 0) { + FDKmemcpy(dmx_re_prev, store_dmx_re_prev, + windowLen * sizeof(FIXP_DBL)); + } + specScaleL[0] = dmx_re_prev_e; + specScaleR[0] = dmx_re_prev_e; + } + } else { /* window != 0 */ + FDK_ASSERT(pAacDecoderChannelInfo[L]->icsInfo.WindowSequence == + BLOCK_SHORT); + if (specScaleL[window - 1] < frameMaxScale) { + for (int i = 0; i < windowLen; i++) { + dmx_re[windowLen * (window - 1) + i] >>= + (frameMaxScale - specScaleL[window - 1]); + } + } else { + specScaleL[window] = specScaleL[window - 1]; + specScaleR[window] = specScaleR[window - 1]; + } + } + } /* if ( pJointStereoData->use_prev_frame == 1 ) */ + + /* scaling factors of both channels ought to be equal now */ + FDK_ASSERT(specScaleL[window] == specScaleR[window]); + + /* rescale signal and calculate downmix MDCT */ + for (band = 0; band < max_sfb_ste; band++) { + /* first adapt scaling of current band to scaling of current window => + * shift signal right */ + int lScale = leftScale[band]; + int rScale = rightScale[band]; + + lScale = fMin(DFRACT_BITS - 1, specScaleL[window] - lScale); + rScale = fMin(DFRACT_BITS - 1, + specScaleL[window] - rScale); /* L or R doesn't + matter, + specScales are + equal at this + point */ + + /* Write back to sfb scale to cover the case when max_sfb_ste < + * max_sfb */ + leftScale[band] = rightScale[band] = specScaleL[window]; + + for (int i = pScaleFactorBandOffsets[band]; + i < pScaleFactorBandOffsets[band + 1]; i++) { + spectrumL[windowLen * window + i] >>= lScale; + spectrumR[windowLen * window + i] >>= rScale; + } + + /* now calculate downmix MDCT */ + if (pJointStereoData->MsUsed[band] & groupMask) { + for (int i = pScaleFactorBandOffsets[band]; + i < pScaleFactorBandOffsets[band + 1]; i++) { + dmx_re[windowLen * window + i] = + spectrumL[windowLen * window + i]; + } + } else { + if (cplxPredictionData->pred_dir == 0) { + for (int i = pScaleFactorBandOffsets[band]; + i < pScaleFactorBandOffsets[band + 1]; i++) { + dmx_re[windowLen * window + i] = + (spectrumL[windowLen * window + i] + + spectrumR[windowLen * window + i]) >> + 1; + } + } else { + for (int i = pScaleFactorBandOffsets[band]; + i < pScaleFactorBandOffsets[band + 1]; i++) { + dmx_re[windowLen * window + i] = + (spectrumL[windowLen * window + i] - + spectrumR[windowLen * window + i]) >> + 1; + } + } + } + + } /* for ( band=0; band<max_sfb_ste; band++ ) */ + /* Clean until the end */ + for (int i = pScaleFactorBandOffsets[max_sfb_ste_outside]; + i < windowLen; i++) { + dmx_re[windowLen * window + i] = (FIXP_DBL)0; + } + + /* 3. calculate MDST-portion corresponding to the current frame. */ + if (cplxPredictionData->complex_coef == 1) { + { + /* 3.1 move pointer in filter-coefficient table in case of short + * window sequence */ + /* (other coefficients are utilized for the last 7 short + * windows) */ + if ((pAacDecoderChannelInfo[L]->icsInfo.WindowSequence == + BLOCK_SHORT) && + (window != 0)) { + pCoeff = mdst_filt_coef_curr[currentShape]; + pCoeffPrev = mdst_filt_coef_prev[currentShape]; + } + + /* The length of the filter processing must be extended because of + * filter boundary problems */ + int extended_band = fMin( + pScaleFactorBandOffsets[max_sfb_ste_outside] + 7, windowLen); + + /* 3.2. estimate downmix MDST from current frame downmix MDCT */ + if ((pAacDecoderChannelInfo[L]->icsInfo.WindowSequence == + BLOCK_SHORT) && + (window != 0)) { + CJointStereo_filterAndAdd(&dmx_re[windowLen * window], + extended_band, windowLen, pCoeff, + &dmx_im[windowLen * window], 1); + + CJointStereo_filterAndAdd(&dmx_re[windowLen * (window - 1)], + extended_band, windowLen, pCoeffPrev, + &dmx_im[windowLen * window], 0); + } else { + CJointStereo_filterAndAdd(dmx_re, extended_band, windowLen, + pCoeff, dmx_im, 1); + + if (cplxPredictionData->use_prev_frame == 1) { + CJointStereo_filterAndAdd(dmx_re_prev, extended_band, windowLen, + pCoeffPrev, + &dmx_im[windowLen * window], 0); + } + } + + } /* if(pAacDecoderChannelInfo[L]->transform_splitting_active) */ + } /* if ( pJointStereoData->complex_coef == 1 ) */ + + /* 4. upmix process */ + INT pred_dir = cplxPredictionData->pred_dir ? -1 : 1; + /* 0.1 in Q-3.34 */ + const FIXP_DBL pointOne = 0x66666666; /* 0.8 */ + /* Shift value for the downmix */ + const INT shift_dmx = SF_FNA_COEFFS + 1; + + for (band = 0; band < max_sfb_ste_outside; band++) { + if (pJointStereoData->MsUsed[band] & groupMask) { + FIXP_SGL tempRe = + (FIXP_SGL)cplxPredictionData->alpha_q_re[group][band]; + FIXP_SGL tempIm = + (FIXP_SGL)cplxPredictionData->alpha_q_im[group][band]; + + /* Find the minimum common headroom for alpha_re and alpha_im */ + int alpha_re_headroom = CountLeadingBits((INT)tempRe) - 16; + if (tempRe == (FIXP_SGL)0) alpha_re_headroom = 15; + int alpha_im_headroom = CountLeadingBits((INT)tempIm) - 16; + if (tempIm == (FIXP_SGL)0) alpha_im_headroom = 15; + int val = fMin(alpha_re_headroom, alpha_im_headroom); + + /* Multiply alpha by 0.1 with maximum precision */ + FDK_ASSERT(val >= 0); + FIXP_DBL alpha_re_tmp = fMult((FIXP_SGL)(tempRe << val), pointOne); + FIXP_DBL alpha_im_tmp = fMult((FIXP_SGL)(tempIm << val), pointOne); + + /* Calculate alpha exponent */ + /* (Q-3.34 * Q15.0) shifted left by "val" */ + int alpha_re_exp = -3 + 15 - val; + + int help3_shift = alpha_re_exp + 1; + + FIXP_DBL *p2CoeffL = &( + spectrumL[windowLen * window + pScaleFactorBandOffsets[band]]); + FIXP_DBL *p2CoeffR = &( + spectrumR[windowLen * window + pScaleFactorBandOffsets[band]]); + FIXP_DBL *p2dmxIm = + &(dmx_im[windowLen * window + pScaleFactorBandOffsets[band]]); + FIXP_DBL *p2dmxRe = + &(dmx_re[windowLen * window + pScaleFactorBandOffsets[band]]); + + for (int i = pScaleFactorBandOffsets[band]; + i < pScaleFactorBandOffsets[band + 1]; i++) { + /* Calculating helper term: + side = specR[i] - alpha_re[i] * dmx_re[i] - alpha_im[i] * + dmx_im[i]; + + Here "dmx_re" may be the same as "specL" or alternatively keep + the downmix. "dmx_re" and "specL" are two different pointers + pointing to separate arrays, which may or may not contain the + same data (with different scaling). + */ + + /* help1: alpha_re[i] * dmx_re[i] */ + FIXP_DBL help1 = fMultDiv2(alpha_re_tmp, *p2dmxRe++); + + /* tmp: dmx_im[i] */ + FIXP_DBL tmp = (*p2dmxIm++) << shift_dmx; + + /* help2: alpha_im[i] * dmx_im[i] */ + FIXP_DBL help2 = fMultDiv2(alpha_im_tmp, tmp); + + /* help3: alpha_re[i] * dmx_re[i] + alpha_im[i] * dmx_im[i] */ + FIXP_DBL help3 = help1 + help2; + + /* side (= help4) = specR[i] - (dmx_re[i] * specL[i] + alpha_im[i] + * * dmx_im[i]) */ + FIXP_DBL help4 = *p2CoeffR - scaleValue(help3, help3_shift); + + /* We calculate the left and right output by using the helper + * function */ + /* specR[i] = -/+ (specL[i] - side); */ + *p2CoeffR = + (FIXP_DBL)((LONG)(*p2CoeffL - help4) * (LONG)pred_dir); + p2CoeffR++; + + /* specL[i] = specL[i] + side; */ + *p2CoeffL = *p2CoeffL + help4; + p2CoeffL++; + } + } + + } /* for ( band=0; band < max_sfb_ste; band++ ) */ + } /* for ( groupwin=0; groupwin<pWindowGroupLength[group]; groupwin++, + window++ ) */ + + } /* for ( window = 0, group = 0; group < windowGroups; group++ ) */ + + /* free scratch buffer */ + C_AALLOC_SCRATCH_END(dmx_im, FIXP_DBL, 1024); + + } else { + /* MS stereo */ + + for (window = 0, group = 0; group < windowGroups; group++) { + groupMask = 1 << group; + + for (int groupwin = 0; groupwin < pWindowGroupLength[group]; + groupwin++, window++) { + FIXP_DBL *leftSpectrum, *rightSpectrum; + SHORT *leftScale = &SFBleftScale[window * 16]; + SHORT *rightScale = &SFBrightScale[window * 16]; + + leftSpectrum = + SPEC(spectrumL, window, pAacDecoderChannelInfo[L]->granuleLength); + rightSpectrum = + SPEC(spectrumR, window, pAacDecoderChannelInfo[R]->granuleLength); + + for (band = 0; band < max_sfb_ste_outside; band++) { + if (pJointStereoData->MsUsed[band] & groupMask) { + int lScale = leftScale[band]; + int rScale = rightScale[band]; + int commonScale = lScale > rScale ? lScale : rScale; + unsigned int offsetCurrBand, offsetNextBand; + + /* ISO/IEC 14496-3 Chapter 4.6.8.1.1 : + M/S joint channel coding can only be used if common_window is 1. + */ + FDK_ASSERT(GetWindowSequence(&pAacDecoderChannelInfo[L]->icsInfo) == + GetWindowSequence(&pAacDecoderChannelInfo[R]->icsInfo)); + FDK_ASSERT(GetWindowShape(&pAacDecoderChannelInfo[L]->icsInfo) == + GetWindowShape(&pAacDecoderChannelInfo[R]->icsInfo)); + + commonScale++; + leftScale[band] = commonScale; + rightScale[band] = commonScale; + + lScale = fMin(DFRACT_BITS - 1, commonScale - lScale); + rScale = fMin(DFRACT_BITS - 1, commonScale - rScale); + + FDK_ASSERT(lScale >= 0 && rScale >= 0); + + offsetCurrBand = pScaleFactorBandOffsets[band]; + offsetNextBand = pScaleFactorBandOffsets[band + 1]; + + CJointStereo_GenerateMSOutput(&(leftSpectrum[offsetCurrBand]), + &(rightSpectrum[offsetCurrBand]), + lScale, rScale, + offsetNextBand - offsetCurrBand); + } + } + if (scaleFactorBandsTransmittedL > scaleFactorBandsTransmitted) { + for (; band < scaleFactorBandsTransmittedL; band++) { + if (pJointStereoData->MsUsed[band] & groupMask) { + rightScale[band] = leftScale[band]; + + for (int index = pScaleFactorBandOffsets[band]; + index < pScaleFactorBandOffsets[band + 1]; index++) { + FIXP_DBL leftCoefficient = leftSpectrum[index]; + /* FIXP_DBL rightCoefficient = (FIXP_DBL)0; */ + rightSpectrum[index] = leftCoefficient; + } + } + } + } else if (scaleFactorBandsTransmittedR > scaleFactorBandsTransmitted) { + for (; band < scaleFactorBandsTransmittedR; band++) { + if (pJointStereoData->MsUsed[band] & groupMask) { + leftScale[band] = rightScale[band]; + + for (int index = pScaleFactorBandOffsets[band]; + index < pScaleFactorBandOffsets[band + 1]; index++) { + /* FIXP_DBL leftCoefficient = (FIXP_DBL)0; */ + FIXP_DBL rightCoefficient = rightSpectrum[index]; + + leftSpectrum[index] = rightCoefficient; + rightSpectrum[index] = -rightCoefficient; + } + } + } + } + } + } + + /* Reset MsUsed flags if no explicit signalling was transmitted. Necessary + for intensity coding. PNS correlation signalling was mapped before + calling CJointStereo_ApplyMS(). */ + if (pJointStereoData->MsMaskPresent == 2) { + FDKmemclear(pJointStereoData->MsUsed, + JointStereoMaximumBands * sizeof(UCHAR)); + } + } +} + +void CJointStereo_ApplyIS(CAacDecoderChannelInfo *pAacDecoderChannelInfo[2], + const SHORT *pScaleFactorBandOffsets, + const UCHAR *pWindowGroupLength, + const int windowGroups, + const int scaleFactorBandsTransmitted) { + CJointStereoData *pJointStereoData = + &pAacDecoderChannelInfo[L]->pComData->jointStereoData; + + for (int window = 0, group = 0; group < windowGroups; group++) { + UCHAR *CodeBook; + SHORT *ScaleFactor; + UCHAR groupMask = 1 << group; + + CodeBook = &pAacDecoderChannelInfo[R]->pDynData->aCodeBook[group * 16]; + ScaleFactor = + &pAacDecoderChannelInfo[R]->pDynData->aScaleFactor[group * 16]; + + for (int groupwin = 0; groupwin < pWindowGroupLength[group]; + groupwin++, window++) { + FIXP_DBL *leftSpectrum, *rightSpectrum; + SHORT *leftScale = + &pAacDecoderChannelInfo[L]->pDynData->aSfbScale[window * 16]; + SHORT *rightScale = + &pAacDecoderChannelInfo[R]->pDynData->aSfbScale[window * 16]; + int band; + + leftSpectrum = SPEC(pAacDecoderChannelInfo[L]->pSpectralCoefficient, + window, pAacDecoderChannelInfo[L]->granuleLength); + rightSpectrum = SPEC(pAacDecoderChannelInfo[R]->pSpectralCoefficient, + window, pAacDecoderChannelInfo[R]->granuleLength); + + for (band = 0; band < scaleFactorBandsTransmitted; band++) { + if ((CodeBook[band] == INTENSITY_HCB) || + (CodeBook[band] == INTENSITY_HCB2)) { + int bandScale = -(ScaleFactor[band] + 100); + + int msb = bandScale >> 2; + int lsb = bandScale & 0x03; + + /* exponent of MantissaTable[lsb][0] is 1, thus msb+1 below. */ + FIXP_DBL scale = MantissaTable[lsb][0]; + + /* ISO/IEC 14496-3 Chapter 4.6.8.2.3 : + The use of intensity stereo coding is signaled by the use of the + pseudo codebooks INTENSITY_HCB and INTENSITY_HCB2 (15 and 14) only + in the right channel of a channel_pair_element() having a common + ics_info() (common_window == 1). */ + FDK_ASSERT(GetWindowSequence(&pAacDecoderChannelInfo[L]->icsInfo) == + GetWindowSequence(&pAacDecoderChannelInfo[R]->icsInfo)); + FDK_ASSERT(GetWindowShape(&pAacDecoderChannelInfo[L]->icsInfo) == + GetWindowShape(&pAacDecoderChannelInfo[R]->icsInfo)); + + rightScale[band] = leftScale[band] + msb + 1; + + if (pJointStereoData->MsUsed[band] & groupMask) { + if (CodeBook[band] == INTENSITY_HCB) /* _NOT_ in-phase */ + { + scale = -scale; + } + } else { + if (CodeBook[band] == INTENSITY_HCB2) /* out-of-phase */ + { + scale = -scale; + } + } + + for (int index = pScaleFactorBandOffsets[band]; + index < pScaleFactorBandOffsets[band + 1]; index++) { + rightSpectrum[index] = fMult(leftSpectrum[index], scale); + } + } + } + } + } +} |