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+/* -----------------------------------------------------------------------------
+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
+----------------------------------------------------------------------------- */
+
+/************************* MPEG-D DRC decoder library **************************
+
+ Author(s):
+
+ Description:
+
+*******************************************************************************/
+
+#include "drcDec_types.h"
+#include "drcDec_gainDecoder.h"
+#include "drcGainDec_process.h"
+
+#define E_TGAINSTEP 12
+
+static DRC_ERROR _prepareLnbIndex(ACTIVE_DRC* pActiveDrc,
+ const int channelOffset,
+ const int drcChannelOffset,
+ const int numChannelsProcessed,
+ const int lnbPointer) {
+ int g, c;
+ DRC_INSTRUCTIONS_UNI_DRC* pInst = pActiveDrc->pInst;
+
+ /* channelOffset: start index of physical channels
+ numChannelsProcessed: number of processed channels, physical channels and
+ DRC channels channelOffset + drcChannelOffset: start index of DRC channels,
+ i.e. the channel order referenced in pInst.sequenceIndex */
+
+ /* sanity checks */
+ if ((channelOffset + numChannelsProcessed) > 8) return DE_NOT_OK;
+
+ if ((channelOffset + drcChannelOffset + numChannelsProcessed) > 8)
+ return DE_NOT_OK;
+
+ if ((channelOffset + drcChannelOffset) < 0) return DE_NOT_OK;
+
+ /* prepare lnbIndexForChannel, a map of indices from each channel to its
+ * corresponding linearNodeBuffer instance */
+ for (c = channelOffset; c < channelOffset + numChannelsProcessed; c++) {
+ if (pInst->drcSetId > 0) {
+ int drcChannel = c + drcChannelOffset;
+ /* fallback for configuration with more physical channels than DRC
+ channels: reuse DRC gain of first channel. This is necessary for HE-AAC
+ mono with stereo output */
+ if (drcChannel >= pInst->drcChannelCount) drcChannel = 0;
+ g = pActiveDrc->channelGroupForChannel[drcChannel];
+ if ((g >= 0) && !pActiveDrc->channelGroupIsParametricDrc[g]) {
+ pActiveDrc->lnbIndexForChannel[c][lnbPointer] =
+ pActiveDrc->activeDrcOffset + pActiveDrc->gainElementForGroup[g];
+ }
+ }
+ }
+
+ return DE_OK;
+}
+
+static DRC_ERROR _interpolateDrcGain(
+ const GAIN_INTERPOLATION_TYPE gainInterpolationType,
+ const SHORT timePrev, /* time0 */
+ const SHORT tGainStep, /* time1 - time0 */
+ const SHORT start, const SHORT stop, const SHORT stepsize,
+ const FIXP_DBL gainLeft, const FIXP_DBL gainRight, const FIXP_DBL slopeLeft,
+ const FIXP_DBL slopeRight, FIXP_DBL* buffer) {
+ int n, n_buf;
+ int start_modulo, start_offset;
+
+ if (tGainStep < 0) {
+ return DE_NOT_OK;
+ }
+ if (tGainStep == 0) {
+ return DE_OK;
+ }
+
+ /* get start index offset and buffer index for downsampled interpolation */
+ /* start_modulo = (start+timePrev)%stepsize; */ /* stepsize is a power of 2 */
+ start_modulo = (start + timePrev) & (stepsize - 1);
+ start_offset = (start_modulo ? stepsize - start_modulo : 0);
+ /* n_buf = (start + timePrev + start_offset)/stepsize; */
+ n_buf = (start + timePrev + start_offset) >> (15 - fixnormz_S(stepsize));
+
+ { /* gainInterpolationType == GIT_LINEAR */
+ LONG a;
+ /* runs = ceil((stop - start - start_offset)/stepsize). This works for
+ * stepsize = 2^N only. */
+ INT runs = (INT)(stop - start - start_offset + stepsize - 1) >>
+ (30 - CountLeadingBits(stepsize));
+ INT n_min = fMin(
+ fMin(CntLeadingZeros(gainRight), CntLeadingZeros(gainLeft)) - 1, 8);
+ a = (LONG)((gainRight << n_min) - (gainLeft << n_min)) / tGainStep;
+ LONG a_step = a * stepsize;
+ n = start + start_offset;
+ a = a * n + (LONG)(gainLeft << n_min);
+ buffer += n_buf;
+#if defined(FUNCTION_interpolateDrcGain_func1)
+ interpolateDrcGain_func1(buffer, a, a_step, n_min, runs);
+#else
+ a -= a_step;
+ n_min = 8 - n_min;
+ for (int i = 0; i < runs; i++) {
+ a += a_step;
+ buffer[i] = fMultDiv2(buffer[i], (FIXP_DBL)a) << n_min;
+ }
+#endif /* defined(FUNCTION_interpolateDrcGain_func1) */
+ }
+ return DE_OK;
+}
+
+static DRC_ERROR _processNodeSegments(
+ const int frameSize, const GAIN_INTERPOLATION_TYPE gainInterpolationType,
+ const int nNodes, const NODE_LIN* pNodeLin, const int offset,
+ const SHORT stepsize,
+ const NODE_LIN nodePrevious, /* the last node of the previous frame */
+ const FIXP_DBL channelGain, FIXP_DBL* buffer) {
+ DRC_ERROR err = DE_OK;
+ SHORT timePrev, duration, start, stop, time;
+ int n;
+ FIXP_DBL gainLin = FL2FXCONST_DBL(1.0f / (float)(1 << 7)), gainLinPrev;
+ FIXP_DBL slopeLin = (FIXP_DBL)0, slopeLinPrev = (FIXP_DBL)0;
+
+ timePrev = nodePrevious.time + offset;
+ gainLinPrev = nodePrevious.gainLin;
+ for (n = 0; n < nNodes; n++) {
+ time = pNodeLin[n].time + offset;
+ duration = time - timePrev;
+ gainLin = pNodeLin[n].gainLin;
+ if (channelGain != FL2FXCONST_DBL(1.0f / (float)(1 << 8)))
+ gainLin =
+ SATURATE_LEFT_SHIFT(fMultDiv2(gainLin, channelGain), 9, DFRACT_BITS);
+
+ if ((timePrev >= (frameSize - 1)) ||
+ (time < 0)) { /* This segment (between previous and current node) lies
+ outside of this audio frame */
+ timePrev = time;
+ gainLinPrev = gainLin;
+ slopeLinPrev = slopeLin;
+ continue;
+ }
+
+ /* start and stop are the boundaries of the region of this segment that lie
+ within this audio frame. Their values are relative to the beginning of
+ this segment. stop is the first sample that isn't processed any more. */
+ start = fMax(-timePrev, 1);
+ stop = fMin(time, (SHORT)(frameSize - 1)) - timePrev + 1;
+
+ err = _interpolateDrcGain(gainInterpolationType, timePrev, duration, start,
+ stop, stepsize, gainLinPrev, gainLin,
+ slopeLinPrev, slopeLin, buffer);
+ if (err) return err;
+
+ timePrev = time;
+ gainLinPrev = gainLin;
+ }
+ return err;
+}
+
+/* process DRC on time-domain signal */
+DRC_ERROR
+processDrcTime(HANDLE_DRC_GAIN_DECODER hGainDec, const int activeDrcIndex,
+ const int delaySamples, const int channelOffset,
+ const int drcChannelOffset, const int numChannelsProcessed,
+ const int timeDataChannelOffset, FIXP_DBL* deinterleavedAudio) {
+ DRC_ERROR err = DE_OK;
+ int c, b, i;
+ ACTIVE_DRC* pActiveDrc = &(hGainDec->activeDrc[activeDrcIndex]);
+ DRC_GAIN_BUFFERS* pDrcGainBuffers = &(hGainDec->drcGainBuffers);
+ int lnbPointer = pDrcGainBuffers->lnbPointer, lnbIx;
+ LINEAR_NODE_BUFFER* pLinearNodeBuffer = pDrcGainBuffers->linearNodeBuffer;
+ LINEAR_NODE_BUFFER* pDummyLnb = &(pDrcGainBuffers->dummyLnb);
+ int offset = 0;
+
+ if (hGainDec->delayMode == DM_REGULAR_DELAY) {
+ offset = hGainDec->frameSize;
+ }
+
+ if ((delaySamples + offset) >
+ (NUM_LNB_FRAMES - 2) *
+ hGainDec->frameSize) /* if delaySamples is too big, NUM_LNB_FRAMES
+ should be increased */
+ return DE_NOT_OK;
+
+ err = _prepareLnbIndex(pActiveDrc, channelOffset, drcChannelOffset,
+ numChannelsProcessed, lnbPointer);
+ if (err) return err;
+
+ deinterleavedAudio +=
+ channelOffset * timeDataChannelOffset; /* apply channelOffset */
+
+ /* signal processing loop */
+ for (c = channelOffset; c < channelOffset + numChannelsProcessed; c++) {
+ if (activeDrcIndex == hGainDec->channelGainActiveDrcIndex)
+ pDrcGainBuffers->channelGain[c][lnbPointer] = hGainDec->channelGain[c];
+
+ b = 0;
+ {
+ LINEAR_NODE_BUFFER *pLnb, *pLnbPrevious;
+ NODE_LIN nodePrevious;
+ int lnbPointerDiff;
+ FIXP_DBL channelGain;
+ /* get pointer to oldest linearNodes */
+ lnbIx = lnbPointer + 1 - NUM_LNB_FRAMES;
+ while (lnbIx < 0) lnbIx += NUM_LNB_FRAMES;
+
+ if (activeDrcIndex == hGainDec->channelGainActiveDrcIndex)
+ channelGain = pDrcGainBuffers->channelGain[c][lnbIx];
+ else
+ channelGain = FL2FXCONST_DBL(1.0f / (float)(1 << 8));
+
+ /* Loop over all node buffers in linearNodeBuffer.
+ All nodes which are not relevant for the current frame are sorted out
+ inside _processNodeSegments. */
+ for (i = 0; i < NUM_LNB_FRAMES - 1; i++) {
+ /* Prepare previous node */
+ if (pActiveDrc->lnbIndexForChannel[c][lnbIx] >= 0)
+ pLnbPrevious = &(
+ pLinearNodeBuffer[pActiveDrc->lnbIndexForChannel[c][lnbIx] + b]);
+ else
+ pLnbPrevious = pDummyLnb;
+ nodePrevious =
+ pLnbPrevious->linearNode[lnbIx][pLnbPrevious->nNodes[lnbIx] - 1];
+ nodePrevious.time -= hGainDec->frameSize;
+ if (channelGain != FL2FXCONST_DBL(1.0f / (float)(1 << 8)))
+ nodePrevious.gainLin = SATURATE_LEFT_SHIFT(
+ fMultDiv2(nodePrevious.gainLin,
+ pDrcGainBuffers->channelGain[c][lnbIx]),
+ 9, DFRACT_BITS);
+
+ /* Prepare current linearNodeBuffer instance */
+ lnbIx++;
+ if (lnbIx >= NUM_LNB_FRAMES) lnbIx = 0;
+
+ /* if lnbIndexForChannel changes over time, use the old indices for
+ * smooth transitions */
+ if (pActiveDrc->lnbIndexForChannel[c][lnbIx] >= 0)
+ pLnb = &(
+ pLinearNodeBuffer[pActiveDrc->lnbIndexForChannel[c][lnbIx] + b]);
+ else /* lnbIndexForChannel = -1 means "no DRC processing", due to
+ drcInstructionsIndex < 0, drcSetId < 0 or channel group < 0 */
+ pLnb = pDummyLnb;
+
+ if (activeDrcIndex == hGainDec->channelGainActiveDrcIndex)
+ channelGain = pDrcGainBuffers->channelGain[c][lnbIx];
+
+ /* number of frames of offset with respect to lnbPointer */
+ lnbPointerDiff = i - (NUM_LNB_FRAMES - 2);
+
+ err = _processNodeSegments(
+ hGainDec->frameSize, pLnb->gainInterpolationType,
+ pLnb->nNodes[lnbIx], pLnb->linearNode[lnbIx],
+ lnbPointerDiff * hGainDec->frameSize + delaySamples + offset, 1,
+ nodePrevious, channelGain, deinterleavedAudio);
+ if (err) return err;
+ }
+ deinterleavedAudio += timeDataChannelOffset; /* proceed to next channel */
+ }
+ }
+ return DE_OK;
+}
+
+/* process DRC on subband-domain signal */
+DRC_ERROR
+processDrcSubband(HANDLE_DRC_GAIN_DECODER hGainDec, const int activeDrcIndex,
+ const int delaySamples, const int channelOffset,
+ const int drcChannelOffset, const int numChannelsProcessed,
+ const int processSingleTimeslot,
+ FIXP_DBL* deinterleavedAudioReal[],
+ FIXP_DBL* deinterleavedAudioImag[]) {
+ DRC_ERROR err = DE_OK;
+ int b, c, g, m, m_start, m_stop, s, i;
+ FIXP_DBL gainSb;
+ DRC_INSTRUCTIONS_UNI_DRC* pInst = hGainDec->activeDrc[activeDrcIndex].pInst;
+ DRC_GAIN_BUFFERS* pDrcGainBuffers = &(hGainDec->drcGainBuffers);
+ ACTIVE_DRC* pActiveDrc = &(hGainDec->activeDrc[activeDrcIndex]);
+ int activeDrcOffset = pActiveDrc->activeDrcOffset;
+ int lnbPointer = pDrcGainBuffers->lnbPointer, lnbIx;
+ LINEAR_NODE_BUFFER* pLinearNodeBuffer = pDrcGainBuffers->linearNodeBuffer;
+ FIXP_DBL(*subbandGains)[4 * 1024 / 256] = hGainDec->subbandGains;
+ FIXP_DBL* dummySubbandGains = hGainDec->dummySubbandGains;
+ SUBBAND_DOMAIN_MODE subbandDomainMode = hGainDec->subbandDomainSupported;
+ int signalIndex = 0;
+ int frameSizeSb = 0;
+ int nDecoderSubbands;
+ SHORT L = 0; /* L: downsampling factor */
+ int offset = 0;
+ FIXP_DBL *audioReal = NULL, *audioImag = NULL;
+
+ if (hGainDec->delayMode == DM_REGULAR_DELAY) {
+ offset = hGainDec->frameSize;
+ }
+
+ if ((delaySamples + offset) >
+ (NUM_LNB_FRAMES - 2) *
+ hGainDec->frameSize) /* if delaySamples is too big, NUM_LNB_FRAMES
+ should be increased */
+ return DE_NOT_OK;
+
+ switch (subbandDomainMode) {
+#if ((1024 / 256) >= (4096 / SUBBAND_DOWNSAMPLING_FACTOR_QMF64))
+ case SDM_QMF64:
+ nDecoderSubbands = SUBBAND_NUM_BANDS_QMF64;
+ L = SUBBAND_DOWNSAMPLING_FACTOR_QMF64;
+ /* analysisDelay = SUBBAND_ANALYSIS_DELAY_QMF64; */
+ break;
+ case SDM_QMF71:
+ nDecoderSubbands = SUBBAND_NUM_BANDS_QMF71;
+ L = SUBBAND_DOWNSAMPLING_FACTOR_QMF71;
+ /* analysisDelay = SUBBAND_ANALYSIS_DELAY_QMF71; */
+ break;
+#else
+ case SDM_QMF64:
+ case SDM_QMF71:
+ /* QMF domain processing is not supported. */
+ return DE_NOT_OK;
+#endif
+ case SDM_STFT256:
+ nDecoderSubbands = SUBBAND_NUM_BANDS_STFT256;
+ L = SUBBAND_DOWNSAMPLING_FACTOR_STFT256;
+ /* analysisDelay = SUBBAND_ANALYSIS_DELAY_STFT256; */
+ break;
+ default:
+ return DE_NOT_OK;
+ }
+
+ /* frameSizeSb = hGainDec->frameSize/L; */ /* L is a power of 2 */
+ frameSizeSb =
+ hGainDec->frameSize >> (15 - fixnormz_S(L)); /* timeslots per frame */
+
+ if ((processSingleTimeslot < 0) || (processSingleTimeslot >= frameSizeSb)) {
+ m_start = 0;
+ m_stop = frameSizeSb;
+ } else {
+ m_start = processSingleTimeslot;
+ m_stop = m_start + 1;
+ }
+
+ err = _prepareLnbIndex(pActiveDrc, channelOffset, drcChannelOffset,
+ numChannelsProcessed, lnbPointer);
+ if (err) return err;
+
+ if (!pActiveDrc->subbandGainsReady) /* only for the first time per frame that
+ processDrcSubband is called */
+ {
+ /* write subbandGains */
+ for (g = 0; g < pInst->nDrcChannelGroups; g++) {
+ b = 0;
+ {
+ LINEAR_NODE_BUFFER* pLnb =
+ &(pLinearNodeBuffer[activeDrcOffset +
+ pActiveDrc->gainElementForGroup[g] + b]);
+ NODE_LIN nodePrevious;
+ int lnbPointerDiff;
+
+ for (m = 0; m < frameSizeSb; m++) {
+ subbandGains[activeDrcOffset + g][b * frameSizeSb + m] =
+ FL2FXCONST_DBL(1.0f / (float)(1 << 7));
+ }
+
+ lnbIx = lnbPointer - (NUM_LNB_FRAMES - 1);
+ while (lnbIx < 0) lnbIx += NUM_LNB_FRAMES;
+
+ /* Loop over all node buffers in linearNodeBuffer.
+ All nodes which are not relevant for the current frame are sorted out
+ inside _processNodeSegments. */
+ for (i = 0; i < NUM_LNB_FRAMES - 1; i++) {
+ /* Prepare previous node */
+ nodePrevious = pLnb->linearNode[lnbIx][pLnb->nNodes[lnbIx] - 1];
+ nodePrevious.time -= hGainDec->frameSize;
+
+ lnbIx++;
+ if (lnbIx >= NUM_LNB_FRAMES) lnbIx = 0;
+
+ /* number of frames of offset with respect to lnbPointer */
+ lnbPointerDiff = i - (NUM_LNB_FRAMES - 2);
+
+ err = _processNodeSegments(
+ hGainDec->frameSize, pLnb->gainInterpolationType,
+ pLnb->nNodes[lnbIx], pLnb->linearNode[lnbIx],
+ lnbPointerDiff * hGainDec->frameSize + delaySamples + offset -
+ (L - 1) / 2,
+ L, nodePrevious, FL2FXCONST_DBL(1.0f / (float)(1 << 8)),
+ &(subbandGains[activeDrcOffset + g][b * frameSizeSb]));
+ if (err) return err;
+ }
+ }
+ }
+ pActiveDrc->subbandGainsReady = 1;
+ }
+
+ for (c = channelOffset; c < channelOffset + numChannelsProcessed; c++) {
+ FIXP_DBL* thisSubbandGainsBuffer;
+ if (pInst->drcSetId > 0)
+ g = pActiveDrc->channelGroupForChannel[c + drcChannelOffset];
+ else
+ g = -1;
+
+ audioReal = deinterleavedAudioReal[signalIndex];
+ if (subbandDomainMode != SDM_STFT256) {
+ audioImag = deinterleavedAudioImag[signalIndex];
+ }
+
+ if ((g >= 0) && !pActiveDrc->channelGroupIsParametricDrc[g]) {
+ thisSubbandGainsBuffer = subbandGains[activeDrcOffset + g];
+ } else {
+ thisSubbandGainsBuffer = dummySubbandGains;
+ }
+
+ for (m = m_start; m < m_stop; m++) {
+ INT n_min = 8;
+ { /* single-band DRC */
+ gainSb = thisSubbandGainsBuffer[m];
+ if (activeDrcIndex == hGainDec->channelGainActiveDrcIndex)
+ gainSb = SATURATE_LEFT_SHIFT(
+ fMultDiv2(gainSb, hGainDec->channelGain[c]), 9, DFRACT_BITS);
+ /* normalize gainSb for keeping signal precision */
+ n_min = fMin(CntLeadingZeros(gainSb) - 1, n_min);
+ gainSb <<= n_min;
+ n_min = 8 - n_min;
+ if (subbandDomainMode ==
+ SDM_STFT256) { /* For STFT filterbank, real and imaginary parts are
+ interleaved. */
+ for (s = 0; s < nDecoderSubbands; s++) {
+ *audioReal = fMultDiv2(*audioReal, gainSb) << n_min;
+ audioReal++;
+ *audioReal = fMultDiv2(*audioReal, gainSb) << n_min;
+ audioReal++;
+ }
+ } else {
+ for (s = 0; s < nDecoderSubbands; s++) {
+ *audioReal = fMultDiv2(*audioReal, gainSb) << n_min;
+ audioReal++;
+ *audioImag = fMultDiv2(*audioImag, gainSb) << n_min;
+ audioImag++;
+ }
+ }
+ }
+ }
+ signalIndex++;
+ }
+ return DE_OK;
+}