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diff --git a/libSBRdec/src/psdec_hybrid.cpp b/libSBRdec/src/psdec_hybrid.cpp new file mode 100644 index 0000000..7fc2c0a --- /dev/null +++ b/libSBRdec/src/psdec_hybrid.cpp @@ -0,0 +1,652 @@ + +/* ----------------------------------------------------------------------------------------------------------- +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 +----------------------------------------------------------------------------------------------------------- */ + +#include "psdec_hybrid.h" + + +#include "fft.h" +#include "sbr_ram.h" + +#include "FDK_tools_rom.h" +#include "sbr_rom.h" + +/******************************************************************************* + Functionname: InitHybridFilterBank + ******************************************************************************* + + Description: Init one instance of HANDLE_HYBRID stuct + + Arguments: + + Return: none + +*******************************************************************************/ + + +SBR_ERROR +InitHybridFilterBank ( HANDLE_HYBRID hs, /*!< Handle to HYBRID struct. */ + SCHAR frameSize, /*!< Framesize (in Qmf súbband samples). */ + SCHAR noBands, /*!< Number of Qmf bands for hybrid filtering. */ + const UCHAR *pResolution ) /*!< Resolution in Qmf bands (length noBands). */ +{ + SCHAR i; + UCHAR maxNoChannels = 0; + + for (i = 0; i < noBands; i++) { + hs->pResolution[i] = pResolution[i]; + if(pResolution[i] > maxNoChannels) + maxNoChannels = pResolution[i]; + } + + hs->nQmfBands = noBands; + hs->frameSize = frameSize; + hs->qmfBufferMove = HYBRID_FILTER_LENGTH - 1; + + hs->sf_mQmfBuffer = 0; + + return SBRDEC_OK; +} + +/******************************************************************************* + Functionname: dualChannelFiltering + ******************************************************************************* + + Description: fast 2-channel real-valued filtering with 6-tap delay. + + Arguments: + + Return: none + +*******************************************************************************/ + +/*! +2 channel filter +<pre> + Filter Coefs: + 0.0, + 0.01899487526049, + 0.0, + -0.07293139167538, + 0.0, + 0.30596630545168, + 0.5, + 0.30596630545168, + 0.0, + -0.07293139167538, + 0.0, + 0.01899487526049, + 0.0 + + + Filter design: + h[q,n] = g[n] * cos(2pi/2 * q * (n-6) ); n = 0..12, q = 0,1; + + -> h[0,n] = g[n] * 1; + -> h[1,n] = g[n] * pow(-1,n); +</pre> +*/ + +static void slotBasedDualChannelFiltering( const FIXP_DBL *pQmfReal, + const FIXP_DBL *pQmfImag, + + FIXP_DBL *mHybridReal, + FIXP_DBL *mHybridImag) +{ + + FIXP_DBL t1, t3, t5, t6; + + /* symmetric filter coefficients */ + + /* you don't have to shift the result after fMult because of p2_13_20 <= 0.5 */ + t1 = fMultDiv2(p2_13_20[1] , ( (pQmfReal[1] >> 1) + (pQmfReal[11] >> 1))); + t3 = fMultDiv2(p2_13_20[3] , ( (pQmfReal[3] >> 1) + (pQmfReal[ 9] >> 1))); + t5 = fMultDiv2(p2_13_20[5] , ( (pQmfReal[5] >> 1) + (pQmfReal[ 7] >> 1))); + t6 = fMultDiv2(p2_13_20[6] , (pQmfReal[6] >> 1) ); + + mHybridReal[0] = (t1 + t3 + t5 + t6) << 2; + mHybridReal[1] = (- t1 - t3 - t5 + t6) << 2; + + t1 = fMultDiv2(p2_13_20[1] , ( (pQmfImag[1] >> 1) + (pQmfImag[11] >> 1))); + t3 = fMultDiv2(p2_13_20[3] , ( (pQmfImag[3] >> 1) + (pQmfImag[ 9] >> 1))); + t5 = fMultDiv2(p2_13_20[5] , ( (pQmfImag[5] >> 1) + (pQmfImag[ 7] >> 1))); + t6 = fMultDiv2(p2_13_20[6] , pQmfImag[6] >> 1 ); + + mHybridImag[0] = (t1 + t3 + t5 + t6) << 2; + mHybridImag[1] = (- t1 - t3 - t5 + t6) << 2; +} + + +/******************************************************************************* + Functionname: eightChannelFiltering + ******************************************************************************* + + Description: fast 8-channel complex-valued filtering with 6-tap delay. + + Arguments: + + Return: none + +*******************************************************************************/ +/*! + 8 channel filter + + Implementation using a FFT of length 8 +<pre> + prototype filter coefficients: + 0.00746082949812 0.02270420949825 0.04546865930473 0.07266113929591 0.09885108575264 0.11793710567217 + 0.125 + 0.11793710567217 0.09885108575264 0.07266113929591 0.04546865930473 0.02270420949825 0.00746082949812 + + Filter design: + N = 13; Q = 8; + h[q,n] = g[n] * exp(j * 2 * pi / Q * (q + .5) * (n - 6)); n = 0..(N-1), q = 0..(Q-1); + + Time Signal: x[t]; + Filter Bank Output + y[q,t] = conv(x[t],h[q,t]) = conv(h[q,t],x[t]) = sum(x[k] * h[q, t - k] ) = sum(h[q, k] * x[t - k] ); k = 0..(N-1); + + y[q,t] = x[t - 12]*h[q, 12] + x[t - 11]*h[q, 11] + x[t - 10]*h[q, 10] + x[t - 9]*h[q, 9] + + x[t - 8]*h[q, 8] + x[t - 7]*h[q, 7] + + x[t - 6]*h[q, 6] + + x[t - 5]*h[q, 5] + x[t - 4]*h[q, 4] + + x[t - 3]*h[q, 3] + x[t - 2]*h[q, 2] + x[t - 1]*h[q, 1] + x[t - 0]*h[q, 0]; + + h'[q, n] = h[q,(N-1)-n] = g[n] * exp(j * 2 * pi / Q * (q + .5) * (6 - n)); n = 0..(N-1), q = 0..(Q-1); + + y[q,t] = x[t - 12]*h'[q, 0] + x[t - 11]*h'[q, 1] + x[t - 10]*h'[q, 2] + x[t - 9]*h'[q, 3] + + x[t - 8]*h'[q, 4] + x[t - 7]*h'[q, 5] + + x[t - 6]*h'[q, 6] + + x[t - 5]*h'[q, 7] + x[t - 4]*h'[q, 8] + + x[t - 3]*h'[q, 9] + x[t - 2]*h'[q, 10] + x[t - 1]*h'[q, 11] + x[t - 0]*h'[q, 12]; + + Try to split off FFT Modulation Term: + FFT(x[t], q) = sum(x[t+k]*exp(-j*2*pi/N *q * k)) + c m + Step 1: h'[q,n] = g[n] * ( exp(j * 2 * pi / 8 * .5 * (6 - n)) ) * ( exp (j * 2 * pi / 8 * q * (6 - n)) ); + + h'[q,n] = g[n] *c[n] * m[q,n]; (see above) + c[n] = exp( j * 2 * pi / 8 * .5 * (6 - n) ); + m[q,n] = exp( j * 2 * pi / 8 * q * (6 - n) ); + + y[q,t] = x[t - 0]*g[0]*c[0]*m[q,0] + x[t - 1]*g[1]*c[ 1]*m[q, 1] + ... + ... + x[t - 12]*g[2]*c[12]*m[q,12]; + + | + n m *exp(-j*2*pi) | n' fft +------------------------------------------------------------------------------------------------------------------------- + 0 exp( j * 2 * pi / 8 * q * 6) -> exp(-j * 2 * pi / 8 * q * 2) | 2 exp(-j * 2 * pi / 8 * q * 0) + 1 exp( j * 2 * pi / 8 * q * 5) -> exp(-j * 2 * pi / 8 * q * 3) | 3 exp(-j * 2 * pi / 8 * q * 1) + 2 exp( j * 2 * pi / 8 * q * 4) -> exp(-j * 2 * pi / 8 * q * 4) | 4 exp(-j * 2 * pi / 8 * q * 2) + 3 exp( j * 2 * pi / 8 * q * 3) -> exp(-j * 2 * pi / 8 * q * 5) | 5 exp(-j * 2 * pi / 8 * q * 3) + 4 exp( j * 2 * pi / 8 * q * 2) -> exp(-j * 2 * pi / 8 * q * 6) | 6 exp(-j * 2 * pi / 8 * q * 4) + 5 exp( j * 2 * pi / 8 * q * 1) -> exp(-j * 2 * pi / 8 * q * 7) | 7 exp(-j * 2 * pi / 8 * q * 5) + 6 exp( j * 2 * pi / 8 * q * 0) | 0 exp(-j * 2 * pi / 8 * q * 6) + 7 exp(-j * 2 * pi / 8 * q * 1) | 1 exp(-j * 2 * pi / 8 * q * 7) + 8 exp(-j * 2 * pi / 8 * q * 2) | 2 + 9 exp(-j * 2 * pi / 8 * q * 3) | 3 + 10 exp(-j * 2 * pi / 8 * q * 4) | 4 + 11 exp(-j * 2 * pi / 8 * q * 5) | 5 + 12 exp(-j * 2 * pi / 8 * q * 6) | 6 + + + now use fft modulation coefficients + m[6] = = fft[0] + m[7] = = fft[1] + m[8] = m[ 0] = fft[2] + m[9] = m[ 1] = fft[3] + m[10] = m[ 2] = fft[4] + m[11] = m[ 3] = fft[5] + m[12] = m[ 4] = fft[6] + m[ 5] = fft[7] + + y[q,t] = ( x[t- 6]*g[ 6]*c[ 6] ) * fft[q,0] + + ( x[t- 7]*g[ 7]*c[ 7] ) * fft[q,1] + + ( x[t- 0]*g[ 0]*c[ 0] + x[t- 8]*g[ 8]*c[ 8] ) * fft[q,2] + + ( x[t- 1]*g[ 1]*c[ 1] + x[t- 9]*g[ 9]*c[ 9] ) * fft[q,3] + + ( x[t- 2]*g[ 2]*c[ 2] + x[t-10]*g[10]*c[10] ) * fft[q,4] + + ( x[t- 3]*g[ 3]*c[ 3] + x[t-11]*g[11]*c[11] ) * fft[q,5] + + ( x[t- 4]*g[ 4]*c[ 4] + x[t-12]*g[12]*c[12] ) * fft[q,6] + + ( x[t- 5]*g[ 5]*c[ 5] ) * fft[q,7]; + + pre twiddle factors c[n] = exp(j * 2 * pi / 8 * .5 * (6 - n)); + n c] | n c[n] | n c[n] +--------------------------------------------------------------------------------------------------- + 0 exp( j * 6 * pi / 8) | 1 exp( j * 5 * pi / 8) | 2 exp( j * 4 * pi / 8) + 3 exp( j * 3 * pi / 8) | 4 exp( j * 2 * pi / 8) | 5 exp( j * 1 * pi / 8) + 6 exp( j * 0 * pi / 8) | 7 exp(-j * 1 * pi / 8) | 8 exp(-j * 2 * pi / 8) + 9 exp(-j * 3 * pi / 8) | 10 exp(-j * 4 * pi / 8) | 11 exp(-j * 5 * pi / 8) + 12 exp(-j * 6 * pi / 8) | | +</pre> +*/ + +/* defining rotation factors for *ChannelFiltering */ + +#define cos0Pi FL2FXCONST_DBL( 1.f) +#define sin0Pi FL2FXCONST_DBL( 0.f) + +#define cos1Pi FL2FXCONST_DBL(-1.f) +#define sin1Pi FL2FXCONST_DBL( 0.f) + +#define cos1Pi_2 FL2FXCONST_DBL( 0.f) +#define sin1Pi_2 FL2FXCONST_DBL( 1.f) + +#define cos1Pi_3 FL2FXCONST_DBL( 0.5f) +#define sin1Pi_3 FL2FXCONST_DBL( 0.86602540378444f) + +#define cos0Pi_4 cos0Pi +#define cos1Pi_4 FL2FXCONST_DBL(0.70710678118655f) +#define cos2Pi_4 cos1Pi_2 +#define cos3Pi_4 (-cos1Pi_4) +#define cos4Pi_4 (-cos0Pi_4) +#define cos5Pi_4 cos3Pi_4 +#define cos6Pi_4 cos2Pi_4 + +#define sin0Pi_4 sin0Pi +#define sin1Pi_4 FL2FXCONST_DBL(0.70710678118655f) +#define sin2Pi_4 sin1Pi_2 +#define sin3Pi_4 sin1Pi_4 +#define sin4Pi_4 sin0Pi_4 +#define sin5Pi_4 (-sin3Pi_4) +#define sin6Pi_4 (-sin2Pi_4) + +#define cos0Pi_8 cos0Pi +#define cos1Pi_8 FL2FXCONST_DBL(0.92387953251129f) +#define cos2Pi_8 cos1Pi_4 +#define cos3Pi_8 FL2FXCONST_DBL(0.38268343236509f) +#define cos4Pi_8 cos2Pi_4 +#define cos5Pi_8 (-cos3Pi_8) +#define cos6Pi_8 (-cos2Pi_8) + +#define sin0Pi_8 sin0Pi +#define sin1Pi_8 cos3Pi_8 +#define sin2Pi_8 sin1Pi_4 +#define sin3Pi_8 cos1Pi_8 +#define sin4Pi_8 sin2Pi_4 +#define sin5Pi_8 sin3Pi_8 +#define sin6Pi_8 sin1Pi_4 + +#if defined(ARCH_PREFER_MULT_32x16) + #define FIXP_HYB FIXP_SGL + #define FIXP_CAST FX_DBL2FX_SGL +#else + #define FIXP_HYB FIXP_DBL + #define FIXP_CAST +#endif + +static const FIXP_HYB cr[13] = +{ + FIXP_CAST(cos6Pi_8), FIXP_CAST(cos5Pi_8), FIXP_CAST(cos4Pi_8), + FIXP_CAST(cos3Pi_8), FIXP_CAST(cos2Pi_8), FIXP_CAST(cos1Pi_8), + FIXP_CAST(cos0Pi_8), + FIXP_CAST(cos1Pi_8), FIXP_CAST(cos2Pi_8), FIXP_CAST(cos3Pi_8), + FIXP_CAST(cos4Pi_8), FIXP_CAST(cos5Pi_8), FIXP_CAST(cos6Pi_8) +}; + +static const FIXP_HYB ci[13] = +{ + FIXP_CAST( sin6Pi_8), FIXP_CAST( sin5Pi_8), FIXP_CAST( sin4Pi_8), + FIXP_CAST( sin3Pi_8), FIXP_CAST( sin2Pi_8), FIXP_CAST( sin1Pi_8), + FIXP_CAST( sin0Pi_8) , + FIXP_CAST(-sin1Pi_8), FIXP_CAST(-sin2Pi_8), FIXP_CAST(-sin3Pi_8), + FIXP_CAST(-sin4Pi_8), FIXP_CAST(-sin5Pi_8), FIXP_CAST(-sin6Pi_8) +}; + +static void slotBasedEightChannelFiltering( const FIXP_DBL *pQmfReal, + const FIXP_DBL *pQmfImag, + + FIXP_DBL *mHybridReal, + FIXP_DBL *mHybridImag) +{ + + int bin; + FIXP_DBL _fft[128 + ALIGNMENT_DEFAULT - 1]; + FIXP_DBL *fft = (FIXP_DBL *)ALIGN_PTR(_fft); + +#if defined(ARCH_PREFER_MULT_32x16) + const FIXP_SGL *p = p8_13_20; /* BASELINE_PS */ +#else + const FIXP_DBL *p = p8_13_20; /* BASELINE_PS */ +#endif + + /* pre twiddeling */ + + /* x*(a*b + c*d) = fMultDiv2(x, fMultAddDiv2(fMultDiv2(a, b), c, d)) */ + /* x*(a*b - c*d) = fMultDiv2(x, fMultSubDiv2(fMultDiv2(a, b), c, d)) */ + FIXP_DBL accu1, accu2, accu3, accu4; + + #define TWIDDLE_1(n_0,n_1,n_2) \ + cplxMultDiv2(&accu1, &accu2, pQmfReal[n_0], pQmfImag[n_0], cr[n_0], ci[n_0]); \ + accu1 = fMultDiv2(p[n_0], accu1); \ + accu2 = fMultDiv2(p[n_0], accu2); \ + cplxMultDiv2(&accu3, &accu4, pQmfReal[n_1], pQmfImag[n_1], cr[n_1], ci[n_1]); \ + accu3 = fMultDiv2(p[n_1], accu3); \ + accu4 = fMultDiv2(p[n_1], accu4); \ + fft[FIXP_FFT_IDX_R(n_2)] = accu1 + accu3; \ + fft[FIXP_FFT_IDX_I(n_2)] = accu2 + accu4; + + #define TWIDDLE_0(n_0,n_1) \ + cplxMultDiv2(&accu1, &accu2, pQmfReal[n_0], pQmfImag[n_0], cr[n_0], ci[n_0]); \ + fft[FIXP_FFT_IDX_R(n_1)] = fMultDiv2(p[n_0], accu1); \ + fft[FIXP_FFT_IDX_I(n_1)] = fMultDiv2(p[n_0], accu2); + + TWIDDLE_0( 6, 0) + TWIDDLE_0( 7, 1) + + TWIDDLE_1( 0, 8, 2) + TWIDDLE_1( 1, 9, 3) + TWIDDLE_1( 2,10, 4) + TWIDDLE_1( 3,11, 5) + TWIDDLE_1( 4,12, 6) + + TWIDDLE_0( 5, 7) + + fft_8 (fft); + + /* resort fft data into output array*/ + for(bin=0; bin<8;bin++ ) { + mHybridReal[bin] = fft[FIXP_FFT_IDX_R(bin)] << 4; + mHybridImag[bin] = fft[FIXP_FFT_IDX_I(bin)] << 4; + } +} + + +/******************************************************************************* + Functionname: fillHybridDelayLine + ******************************************************************************* + + Description: The delay line of the hybrid filter is filled and copied from + left to right. + + Return: none + +*******************************************************************************/ + +void +fillHybridDelayLine( FIXP_DBL **fixpQmfReal, /*!< Qmf real Values */ + FIXP_DBL **fixpQmfImag, /*!< Qmf imag Values */ + FIXP_DBL fixpHybridLeftR[12], /*!< Hybrid real Values left channel */ + FIXP_DBL fixpHybridLeftI[12], /*!< Hybrid imag Values left channel */ + FIXP_DBL fixpHybridRightR[12], /*!< Hybrid real Values right channel */ + FIXP_DBL fixpHybridRightI[12], /*!< Hybrid imag Values right channel */ + HANDLE_HYBRID hHybrid ) +{ + int i; + + for (i = 0; i < HYBRID_FILTER_DELAY; i++) { + slotBasedHybridAnalysis ( fixpQmfReal[i], + fixpQmfReal[i], + fixpHybridLeftR, + fixpHybridLeftI, + hHybrid ); + } + + FDKmemcpy(fixpHybridRightR, fixpHybridLeftR, sizeof(FIXP_DBL)*NO_SUB_QMF_CHANNELS); + FDKmemcpy(fixpHybridRightI, fixpHybridLeftI, sizeof(FIXP_DBL)*NO_SUB_QMF_CHANNELS); +} + + +/******************************************************************************* + Functionname: slotBasedHybridAnalysis + ******************************************************************************* + + Description: The lower QMF subbands are further split to provide better + frequency resolution for PS processing. + + Return: none + +*******************************************************************************/ + + +void +slotBasedHybridAnalysis ( FIXP_DBL *fixpQmfReal, /*!< Qmf real Values */ + FIXP_DBL *fixpQmfImag, /*!< Qmf imag Values */ + + FIXP_DBL fixpHybridReal[12], /*!< Hybrid real Values */ + FIXP_DBL fixpHybridImag[12], /*!< Hybrid imag Values */ + + HANDLE_HYBRID hHybrid) +{ + int k, band; + HYBRID_RES hybridRes; + int chOffset = 0; + + C_ALLOC_SCRATCH_START(pTempRealSlot, FIXP_DBL, 4*HYBRID_FILTER_LENGTH); + + FIXP_DBL *pTempImagSlot = pTempRealSlot + HYBRID_FILTER_LENGTH; + FIXP_DBL *pWorkRealSlot = pTempImagSlot + HYBRID_FILTER_LENGTH; + FIXP_DBL *pWorkImagSlot = pWorkRealSlot + HYBRID_FILTER_LENGTH; + + /*! + Hybrid filtering is applied to the first hHybrid->nQmfBands QMF bands (3 when 10 or 20 stereo bands + are used, 5 when 34 stereo bands are used). For the remaining QMF bands a delay would be necessary. + But there is no need to implement a delay because there is a look-ahead of HYBRID_FILTER_DELAY = 6 + QMF samples in the low-band buffer. + */ + + for(band = 0; band < hHybrid->nQmfBands; band++) { + + /* get hybrid resolution per qmf band */ + /* in case of baseline ps 10/20 band stereo mode : */ + /* */ + /* qmfBand[0] : 8 ( HYBRID_8_CPLX ) */ + /* qmfBand[1] : 2 ( HYBRID_2_REAL ) */ + /* qmfBand[2] : 2 ( HYBRID_2_REAL ) */ + /* */ + /* (split the 3 lower qmf band to 12 hybrid bands) */ + + hybridRes = (HYBRID_RES)hHybrid->pResolution[band]; + + FDKmemcpy(pWorkRealSlot, hHybrid->mQmfBufferRealSlot[band], hHybrid->qmfBufferMove * sizeof(FIXP_DBL)); + FDKmemcpy(pWorkImagSlot, hHybrid->mQmfBufferImagSlot[band], hHybrid->qmfBufferMove * sizeof(FIXP_DBL)); + + pWorkRealSlot[hHybrid->qmfBufferMove] = fixpQmfReal[band]; + pWorkImagSlot[hHybrid->qmfBufferMove] = fixpQmfImag[band]; + + FDKmemcpy(hHybrid->mQmfBufferRealSlot[band], pWorkRealSlot + 1, hHybrid->qmfBufferMove * sizeof(FIXP_DBL)); + FDKmemcpy(hHybrid->mQmfBufferImagSlot[band], pWorkImagSlot + 1, hHybrid->qmfBufferMove * sizeof(FIXP_DBL)); + + if (fixpQmfReal) { + + /* actual filtering only if output signal requested */ + switch( hybridRes ) { + + /* HYBRID_2_REAL & HYBRID_8_CPLX are only needful for baseline ps */ + case HYBRID_2_REAL: + + slotBasedDualChannelFiltering( pWorkRealSlot, + pWorkImagSlot, + pTempRealSlot, + pTempImagSlot); + break; + + case HYBRID_8_CPLX: + + slotBasedEightChannelFiltering( pWorkRealSlot, + pWorkImagSlot, + pTempRealSlot, + pTempImagSlot); + break; + + default: + FDK_ASSERT(0); + } + + for(k = 0; k < (SCHAR)hybridRes; k++) { + fixpHybridReal [chOffset + k] = pTempRealSlot[k]; + fixpHybridImag [chOffset + k] = pTempImagSlot[k]; + } + chOffset += hybridRes; + } /* if (mHybridReal) */ + } + + /* group hybrid channels 3+4 -> 3 and 2+5 -> 2 */ + fixpHybridReal[3] += fixpHybridReal[4]; + fixpHybridImag[3] += fixpHybridImag[4]; + fixpHybridReal[4] = (FIXP_DBL)0; + fixpHybridImag[4] = (FIXP_DBL)0; + + fixpHybridReal[2] += fixpHybridReal[5]; + fixpHybridImag[2] += fixpHybridImag[5]; + fixpHybridReal[5] = (FIXP_DBL)0; + fixpHybridImag[5] = (FIXP_DBL)0; + + /* free memory on scratch */ + C_ALLOC_SCRATCH_END(pTempRealSlot, FIXP_DBL, 4*HYBRID_FILTER_LENGTH); + +} + + +/******************************************************************************* + Functionname: slotBasedHybridSynthesis + ******************************************************************************* + + Description: The coefficients offering higher resolution for the lower QMF + channel are simply added prior to the synthesis with the 54 + subbands QMF. + + Arguments: + + Return: none + +*******************************************************************************/ + +/*! <pre> + l,r0(n) ---\ + l,r1(n) ---- + --\ + l,r2(n) ---/ \ + + --> F0(w) + l,r3(n) ---\ / + l,r4(n) ---- + --/ + l,r5(n) ---/ + + + l,r6(n) ---\ + + ---------> F1(w) + l,r7(n) ---/ + + + l,r8(n) ---\ + + ---------> F2(w) + l,r9(n) ---/ + + </pre> + Hybrid QMF synthesis filterbank for the 10 and 20 stereo-bands configurations. The + coefficients offering higher resolution for the lower QMF channel are simply added + prior to the synthesis with the 54 subbands QMF. + + [see ISO/IEC 14496-3:2001/FDAM 2:2004(E) - Page 52] +*/ + + +void +slotBasedHybridSynthesis ( FIXP_DBL *fixpHybridReal, /*!< Hybrid real Values */ + FIXP_DBL *fixpHybridImag, /*!< Hybrid imag Values */ + FIXP_DBL *fixpQmfReal, /*!< Qmf real Values */ + FIXP_DBL *fixpQmfImag, /*!< Qmf imag Values */ + HANDLE_HYBRID hHybrid ) /*!< Handle to HYBRID struct. */ +{ + int k, band; + + HYBRID_RES hybridRes; + int chOffset = 0; + + for(band = 0; band < hHybrid->nQmfBands; band++) { + + FIXP_DBL qmfReal = FL2FXCONST_DBL(0.f); + FIXP_DBL qmfImag = FL2FXCONST_DBL(0.f); + hybridRes = (HYBRID_RES)hHybrid->pResolution[band]; + + for(k = 0; k < (SCHAR)hybridRes; k++) { + qmfReal += fixpHybridReal[chOffset + k]; + qmfImag += fixpHybridImag[chOffset + k]; + } + + fixpQmfReal[band] = qmfReal; + fixpQmfImag[band] = qmfImag; + + chOffset += hybridRes; + } +} + + + |