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Diffstat (limited to 'libSBRdec/src/sbrdec_drc.cpp')
| -rw-r--r-- | libSBRdec/src/sbrdec_drc.cpp | 512 |
1 files changed, 512 insertions, 0 deletions
diff --git a/libSBRdec/src/sbrdec_drc.cpp b/libSBRdec/src/sbrdec_drc.cpp new file mode 100644 index 0000000..ce5247a --- /dev/null +++ b/libSBRdec/src/sbrdec_drc.cpp @@ -0,0 +1,512 @@ + +/* ----------------------------------------------------------------------------------------------------------- +Software License for The Fraunhofer FDK AAC Codec Library for Android + +© Copyright 1995 - 2012 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-4 AAC Decoder ************************** + + Author(s): Christian Griebel + Description: Dynamic range control (DRC) decoder tool for SBR + +******************************************************************************/ + +#include "sbrdec_drc.h" + + +/* DRC - Offset table for QMF interpolation. */ +static const int offsetTab[2][16] = +{ + { 0, 4, 8, 12, 16, 20, 24, 28, 0, 0, 0, 0, 0, 0, 0, 0 }, /* 1024 framing */ + { 0, 4, 8, 12, 16, 19, 22, 26, 0, 0, 0, 0, 0, 0, 0, 0 } /* 960 framing */ +}; + +/*! + \brief Initialize DRC QMF factors + + \hDrcData Handle to DRC channel data. + + \return none +*/ +void sbrDecoder_drcInitChannel ( + HANDLE_SBR_DRC_CHANNEL hDrcData ) +{ + int band; + + if (hDrcData == NULL) { + return; + } + + for (band = 0; band < (64); band++) { + hDrcData->prevFact_mag[band] = (FIXP_DBL)MAXVAL_DBL /*FL2FXCONST_DBL(1.0f)*/; + } + + for (band = 0; band < SBRDEC_MAX_DRC_BANDS; band++) { + hDrcData->currFact_mag[band] = (FIXP_DBL)MAXVAL_DBL /*FL2FXCONST_DBL(1.0f)*/; + hDrcData->nextFact_mag[band] = (FIXP_DBL)MAXVAL_DBL /*FL2FXCONST_DBL(1.0f)*/; + } + + hDrcData->prevFact_exp = 0; + hDrcData->currFact_exp = 0; + hDrcData->nextFact_exp = 0; + + hDrcData->numBandsCurr = 0; + hDrcData->numBandsNext = 0; + + hDrcData->winSequenceCurr = 0; + hDrcData->winSequenceNext = 0; + + hDrcData->drcInterpolationSchemeCurr = 0; + hDrcData->drcInterpolationSchemeNext = 0; + + hDrcData->enable = 0; +} + + +/*! + \brief Swap DRC QMF scaling factors after they have been applied. + + \hDrcData Handle to DRC channel data. + + \return none +*/ +void sbrDecoder_drcUpdateChannel ( + HANDLE_SBR_DRC_CHANNEL hDrcData ) +{ + if (hDrcData == NULL) { + return; + } + if (hDrcData->enable != 1) { + return; + } + + /* swap previous data */ + FDKmemcpy( hDrcData->currFact_mag, + hDrcData->nextFact_mag, + SBRDEC_MAX_DRC_BANDS * sizeof(FIXP_DBL) ); + + hDrcData->currFact_exp = hDrcData->nextFact_exp; + + hDrcData->numBandsCurr = hDrcData->numBandsNext; + + FDKmemcpy( hDrcData->bandTopCurr, + hDrcData->bandTopNext, + SBRDEC_MAX_DRC_BANDS * sizeof(USHORT) ); + + hDrcData->drcInterpolationSchemeCurr = hDrcData->drcInterpolationSchemeNext; + + hDrcData->winSequenceCurr = hDrcData->winSequenceNext; +} + + +/*! + \brief Apply DRC factors slot based. + + \hDrcData Handle to DRC channel data. + \qmfRealSlot Pointer to real valued QMF data of one time slot. + \qmfImagSlot Pointer to the imaginary QMF data of one time slot. + \col Number of the time slot. + \numQmfSubSamples Total number of time slots for one frame. + \scaleFactor Pointer to the out scale factor of the time slot. + + \return None. +*/ +void sbrDecoder_drcApplySlot ( + HANDLE_SBR_DRC_CHANNEL hDrcData, + FIXP_DBL *qmfRealSlot, + FIXP_DBL *qmfImagSlot, + int col, + int numQmfSubSamples, + int maxShift + ) +{ + const int *offset; + + int band, bottomMdct, topMdct, bin, useLP; + int indx = numQmfSubSamples - (numQmfSubSamples >> 1) - 10; /* l_border */ + int frameLenFlag = (numQmfSubSamples == 30) ? 1 : 0; + + const FIXP_DBL *fact_mag = NULL; + INT fact_exp = 0; + UINT numBands = 0; + USHORT *bandTop = NULL; + int shortDrc = 0; + + FIXP_DBL alphaValue = FL2FXCONST_DBL(0.0f); + + if (hDrcData == NULL) { + return; + } + if (hDrcData->enable != 1) { + return; + } + + offset = offsetTab[frameLenFlag]; + + useLP = (qmfImagSlot == NULL) ? 1 : 0; + + col += indx; + bottomMdct = 0; + bin = 0; + + /* get respective data and calc interpolation factor */ + if (col < (numQmfSubSamples>>1)) { /* first half of current frame */ + if (hDrcData->winSequenceCurr != 2) { /* long window */ + int j = col + (numQmfSubSamples>>1); + + if (hDrcData->drcInterpolationSchemeCurr == 0) { + INT k = (frameLenFlag) ? 0x4444444 : 0x4000000; + + alphaValue = (FIXP_DBL)(j * k); + } + else { + if (j >= offset[hDrcData->drcInterpolationSchemeCurr - 1]) { + alphaValue = FL2FXCONST_DBL(1.0f); + } + } + } + else { /* short windows */ + shortDrc = 1; + } + + fact_mag = hDrcData->currFact_mag; + fact_exp = hDrcData->currFact_exp; + numBands = hDrcData->numBandsCurr; + bandTop = hDrcData->bandTopCurr; + } + else if (col < numQmfSubSamples) { /* second half of current frame */ + if (hDrcData->winSequenceNext != 2) { /* next: long window */ + int j = col - (numQmfSubSamples>>1); + + if (hDrcData->drcInterpolationSchemeNext == 0) { + INT k = (frameLenFlag) ? 0x4444444 : 0x4000000; + + alphaValue = (FIXP_DBL)(j * k); + } + else { + if (j >= offset[hDrcData->drcInterpolationSchemeNext - 1]) { + alphaValue = FL2FXCONST_DBL(1.0f); + } + } + + fact_mag = hDrcData->nextFact_mag; + fact_exp = hDrcData->nextFact_exp; + numBands = hDrcData->numBandsNext; + bandTop = hDrcData->bandTopNext; + } + else { /* next: short windows */ + if (hDrcData->winSequenceCurr != 2) { /* current: long window */ + alphaValue = (FIXP_DBL)0; + + fact_mag = hDrcData->nextFact_mag; + fact_exp = hDrcData->nextFact_exp; + numBands = hDrcData->numBandsNext; + bandTop = hDrcData->bandTopNext; + } + else { /* current: short windows */ + shortDrc = 1; + + fact_mag = hDrcData->currFact_mag; + fact_exp = hDrcData->currFact_exp; + numBands = hDrcData->numBandsCurr; + bandTop = hDrcData->bandTopCurr; + } + } + } + else { /* first half of next frame */ + if (hDrcData->winSequenceNext != 2) { /* long window */ + int j = col - (numQmfSubSamples>>1); + + if (hDrcData->drcInterpolationSchemeNext == 0) { + INT k = (frameLenFlag) ? 0x4444444 : 0x4000000; + + alphaValue = (FIXP_DBL)(j * k); + } + else { + if (j >= offset[hDrcData->drcInterpolationSchemeNext - 1]) { + alphaValue = FL2FXCONST_DBL(1.0f); + } + } + } + else { /* short windows */ + shortDrc = 1; + } + + fact_mag = hDrcData->nextFact_mag; + fact_exp = hDrcData->nextFact_exp; + numBands = hDrcData->numBandsNext; + bandTop = hDrcData->bandTopNext; + + col -= numQmfSubSamples; + } + + + /* process bands */ + for (band = 0; band < (int)numBands; band++) { + int bottomQmf, topQmf; + + FIXP_DBL drcFact_mag = FL2FXCONST_DBL(1.0f); + + topMdct = (bandTop[band]+1) << 2; + + if (!shortDrc) { /* long window */ + if (frameLenFlag) { + /* 960 framing */ + bottomMdct = 30 * (bottomMdct / 30); + topMdct = 30 * (topMdct / 30); + + bottomQmf = fMultIfloor((FIXP_DBL)0x4444444, bottomMdct); + topQmf = fMultIfloor((FIXP_DBL)0x4444444, topMdct); + } + else { + /* 1024 framing */ + bottomMdct &= ~0x1f; + topMdct &= ~0x1f; + + bottomQmf = bottomMdct >> 5; + topQmf = topMdct >> 5; + } + + if (band == ((int)numBands-1)) { + topQmf = (64); + } + + for (bin = bottomQmf; bin < topQmf; bin++) { + FIXP_DBL drcFact1_mag = hDrcData->prevFact_mag[bin]; + FIXP_DBL drcFact2_mag = fact_mag[band]; + + /* normalize scale factors */ + if (hDrcData->prevFact_exp < maxShift) { + drcFact1_mag >>= maxShift - hDrcData->prevFact_exp; + } + if (fact_exp < maxShift) { + drcFact2_mag >>= maxShift - fact_exp; + } + + /* interpolate */ + drcFact_mag = fMult(alphaValue, drcFact2_mag) + fMult((FL2FXCONST_DBL(1.0f) - alphaValue), drcFact1_mag); + + /* apply scaling */ + qmfRealSlot[bin] = fMult(qmfRealSlot[bin], drcFact_mag); + if (!useLP) { + qmfImagSlot[bin] = fMult(qmfImagSlot[bin], drcFact_mag); + } + + /* save previous factors */ + if (col == (numQmfSubSamples>>1)-1) { + hDrcData->prevFact_mag[bin] = fact_mag[band]; + } + } + } + else { /* short windows */ + int startSample, stopSample; + FIXP_DBL invFrameSizeDiv8 = (frameLenFlag) ? (FIXP_DBL)0x1111111 : (FIXP_DBL)0x1000000; + + if (frameLenFlag) { + /* 960 framing */ + bottomMdct = 30/8 * (bottomMdct*8/30); + topMdct = 30/8 * (topMdct*8/30); + } + else { + /* 1024 framing */ + bottomMdct &= ~0x03; + topMdct &= ~0x03; + } + + /* startSample is truncated to the nearest corresponding start subsample in + the QMF of the short window bottom is present in:*/ + startSample = ((fMultIfloor( invFrameSizeDiv8, bottomMdct ) & 0x7) * numQmfSubSamples) >> 3; + + /* stopSample is rounded upwards to the nearest corresponding stop subsample + in the QMF of the short window top is present in. */ + stopSample = ((fMultIceil( invFrameSizeDiv8, topMdct ) & 0xf) * numQmfSubSamples) >> 3; + + bottomQmf = fMultIfloor( invFrameSizeDiv8, ((bottomMdct%(numQmfSubSamples<<2)) << 5) ); + topQmf = fMultIfloor( invFrameSizeDiv8, ((topMdct%(numQmfSubSamples<<2)) << 5) ); + + /* extend last band */ + if (band == ((int)numBands-1)) { + topQmf = (64); + stopSample = numQmfSubSamples; + } + + if (topQmf == 0) { + topQmf = (64); + } + + /* save previous factors */ + if (stopSample == numQmfSubSamples) { + int tmpBottom = bottomQmf; + + if (((numQmfSubSamples-1) & ~0x03) > startSample) { + tmpBottom = 0; /* band starts in previous short window */ + } + + for (bin = tmpBottom; bin < topQmf; bin++) { + hDrcData->prevFact_mag[bin] = fact_mag[band]; + } + } + + /* apply */ + if ((col >= startSample) && (col < stopSample)) { + if ((col & ~0x03) > startSample) { + bottomQmf = 0; /* band starts in previous short window */ + } + if (col < ((stopSample-1) & ~0x03)) { + topQmf = (64); /* band ends in next short window */ + } + + drcFact_mag = fact_mag[band]; + + /* normalize scale factor */ + if (fact_exp < maxShift) { + drcFact_mag >>= maxShift - fact_exp; + } + + /* apply scaling */ + for (bin = bottomQmf; bin < topQmf; bin++) { + qmfRealSlot[bin] = fMult(qmfRealSlot[bin], drcFact_mag); + if (!useLP) { + qmfImagSlot[bin] = fMult(qmfImagSlot[bin], drcFact_mag); + } + } + } + } + + bottomMdct = topMdct; + } /* end of bands loop */ + + if (col == (numQmfSubSamples>>1)-1) { + hDrcData->prevFact_exp = fact_exp; + } +} + + +/*! + \brief Apply DRC factors frame based. + + \hDrcData Handle to DRC channel data. + \qmfRealSlot Pointer to real valued QMF data of the whole frame. + \qmfImagSlot Pointer to the imaginary QMF data of the whole frame. + \numQmfSubSamples Total number of time slots for one frame. + \scaleFactor Pointer to the out scale factor of the frame. + + \return None. +*/ +void sbrDecoder_drcApply ( + HANDLE_SBR_DRC_CHANNEL hDrcData, + FIXP_DBL **QmfBufferReal, + FIXP_DBL **QmfBufferImag, + int numQmfSubSamples, + int *scaleFactor + ) +{ + int col; + int maxShift = 0; + + /* get max scale factor */ + if (hDrcData->prevFact_exp > maxShift) { + maxShift = hDrcData->prevFact_exp; + } + if (hDrcData->currFact_exp > maxShift) { + maxShift = hDrcData->currFact_exp; + } + if (hDrcData->nextFact_exp > maxShift) { + maxShift = hDrcData->nextFact_exp; + } + + for (col = 0; col < numQmfSubSamples; col++) + { + FIXP_DBL *qmfSlotReal = QmfBufferReal[col]; + FIXP_DBL *qmfSlotImag = (QmfBufferImag == NULL) ? NULL : QmfBufferImag[col]; + + sbrDecoder_drcApplySlot ( + hDrcData, + qmfSlotReal, + qmfSlotImag, + col, + numQmfSubSamples, + maxShift + ); + } + + *scaleFactor += maxShift; +} + |