Fraunhofer AAC codec.

License boilerplate update to follow.

Change-Id: I2810460c11a58b6d148d84673cc031f3685e79b5

1 files changed, 836 insertions, 0 deletions

diff --git a/libSBRenc/src/psenc_hybrid.cpp b/libSBRenc/src/psenc_hybrid.cpp
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+++ b/libSBRenc/src/psenc_hybrid.cpp
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+/*****************************  MPEG Audio Encoder  ***************************
+
+                     (C) Copyright Fraunhofer IIS (2004-2005)
+                               All Rights Reserved
+
+    Please be advised that this software and/or program delivery is
+    Confidential Information of Fraunhofer and subject to and covered by the
+
+    Fraunhofer IIS Software Evaluation Agreement
+    between Google Inc. and  Fraunhofer
+    effective and in full force since March 1, 2012.
+
+    You may use this software and/or program only under the terms and
+    conditions described in the above mentioned Fraunhofer IIS Software
+    Evaluation Agreement. Any other and/or further use requires a separate agreement.
+
+
+   $Id$
+   Initial author:       M. Neuendorf, M. Multrus
+   contents/description: hybrid analysis filter bank
+
+   This software and/or program is protected by copyright law and international
+   treaties. Any reproduction or distribution of this software and/or program,
+   or any portion of it, may result in severe civil and criminal penalties, and
+   will be prosecuted to the maximum extent possible under law.
+
+******************************************************************************/
+
+#include "psenc_hybrid.h"
+
+
+/* Includes ******************************************************************/
+
+#include "psenc_hybrid.h"
+#include "sbr_ram.h"
+
+#include "fft.h"
+
+#include "genericStds.h"
+
+/* Defines *******************************************************************/
+
+#define HYBRID_SCALE                    4
+
+/*//#define FAST_FILTER2
+#define FAST_FILTER4
+#define FAST_FILTER8
+#define FAST_FILTER12
+*/
+#define HYBRID_INVERSE_ORDER            ( 0x0F000000 )
+#define HYBRID_INVERSE_MASK             ( ~HYBRID_INVERSE_ORDER )
+
+//#define REAL                            ( 0 )
+//#define CPLX                            ( 1 )
+
+#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
+
+#define cos0Pi_12 cos0Pi
+#define cos1Pi_12 FL2FXCONST_DBL(0.96592582628906f)
+#define cos2Pi_12 FL2FXCONST_DBL(0.86602540378444f)
+#define cos3Pi_12 cos1Pi_4
+#define cos4Pi_12 cos1Pi_3
+#define cos5Pi_12 FL2FXCONST_DBL(0.25881904510252f)
+#define cos6Pi_12 cos1Pi_2
+
+#define sin0Pi_12 sin0Pi
+#define sin1Pi_12 cos5Pi_12
+#define sin2Pi_12 cos4Pi_12
+#define sin3Pi_12 sin1Pi_4
+#define sin4Pi_12 sin1Pi_3
+#define sin5Pi_12 cos1Pi_12
+#define sin6Pi_12 sin1Pi_2
+
+#define FFT_IDX_R(a)  (2*a)
+#define FFT_IDX_I(a)  (2*a+1)
+
+
+/* Constants *****************************************************************/
+
+/* static const UINT noQmfBandsInHybrid34 = 5; */
+
+static const INT aHybridResolution10[] = { HYBRID_6_CPLX,
+                                           HYBRID_2_REAL | HYBRID_INVERSE_ORDER,
+                                           HYBRID_2_REAL };
+
+static const INT aHybridResolution20[] = { HYBRID_6_CPLX,
+                                           HYBRID_2_REAL | HYBRID_INVERSE_ORDER,
+                                           HYBRID_2_REAL };
+
+/*static const INT aHybridResolution34[] = { HYBRID_12_CPLX,
+                                           HYBRID_8_CPLX,
+                                           HYBRID_4_CPLX,
+                                           HYBRID_4_CPLX,
+                                           HYBRID_4_CPLX };*/
+
+static const FIXP_DBL p8_13_20[HYBRID_FILTER_LENGTH] =
+{
+  FL2FXCONST_DBL(0.00746082949812f),  FL2FXCONST_DBL(0.02270420949825f),  FL2FXCONST_DBL(0.04546865930473f),  FL2FXCONST_DBL(0.07266113929591f),
+  FL2FXCONST_DBL(0.09885108575264f),  FL2FXCONST_DBL(0.11793710567217f),  FL2FXCONST_DBL(0.125f           ),  FL2FXCONST_DBL(0.11793710567217f),
+  FL2FXCONST_DBL(0.09885108575264f),  FL2FXCONST_DBL(0.07266113929591f),  FL2FXCONST_DBL(0.04546865930473f),  FL2FXCONST_DBL(0.02270420949825f),
+  FL2FXCONST_DBL(0.00746082949812f)
+};
+
+static const FIXP_DBL p2_13_20[HYBRID_FILTER_LENGTH] =
+{
+  FL2FXCONST_DBL(0.0f), FL2FXCONST_DBL( 0.01899487526049f),  FL2FXCONST_DBL(0.0f), FL2FXCONST_DBL(-0.07293139167538f),
+  FL2FXCONST_DBL(0.0f), FL2FXCONST_DBL( 0.30596630545168f),  FL2FXCONST_DBL(0.5f), FL2FXCONST_DBL( 0.30596630545168f),
+  FL2FXCONST_DBL(0.0f), FL2FXCONST_DBL(-0.07293139167538f),  FL2FXCONST_DBL(0.0f), FL2FXCONST_DBL( 0.01899487526049f),
+  FL2FXCONST_DBL(0.0f)
+};
+
+
+/*static const float p12_13_34[HYBRID_FILTER_LENGTH] =
+{
+  0.04081179924692,  0.03812810994926,  0.05144908135699,  0.06399831151592,
+  0.07428313801106,  0.08100347892914,  0.08333333333333,  0.08100347892914,
+  0.07428313801106,  0.06399831151592,  0.05144908135699,  0.03812810994926,
+  0.04081179924692
+};
+
+static const float p8_13_34[HYBRID_FILTER_LENGTH] =
+{
+  0.01565675600122,  0.03752716391991,  0.05417891378782,  0.08417044116767,
+  0.10307344158036,  0.12222452249753,  0.12500000000000,  0.12222452249753,
+  0.10307344158036,  0.08417044116767,  0.05417891378782,  0.03752716391991,
+  0.01565675600122
+};
+
+static const float p4_13_34[HYBRID_FILTER_LENGTH] =
+{
+ -0.05908211155639, -0.04871498374946,  0.0,               0.07778723915851,
+  0.16486303567403,  0.23279856662996,  0.25,              0.23279856662996,
+  0.16486303567403,  0.07778723915851,  0.0,              -0.04871498374946,
+ -0.05908211155639
+};*/
+
+
+/* Function / Class Implementation *******************************************/
+
+
+
+/*****************************************************************************/
+/* **** FILTERBANK CONFIG **** */
+
+HANDLE_ERROR_INFO FDKsbrEnc_CreateHybridConfig(HANDLE_PS_HYBRID_CONFIG *phHybConfig,
+                                               PS_BANDS mode)
+{
+  HANDLE_ERROR_INFO error = noError;
+  HANDLE_PS_HYBRID_CONFIG h = NULL;
+  UINT k = 0;
+
+  if (error == noError) {
+    h = *phHybConfig; /* Simplify your life */
+    h->mode = mode;
+
+    switch (mode) {
+    case PS_BANDS_MID:
+      h->noQmfBandsInHybrid = NO_QMF_BANDS_HYBRID_20;
+      for (k=0; k<h->noQmfBandsInHybrid; k++) {
+        h->aHybridResolution[k] = aHybridResolution20[k];
+      }
+      break;
+
+    case PS_BANDS_FINE:
+      /*h->noQmfBandsInHybrid = noQmfBandsInHybrid34;
+      for (k=0; k<h->noQmfBandsInHybrid; k++) {
+        h->aHybridResolution[k] = aHybridResolution34[k];
+      }*/
+      FDK_ASSERT(0); /* we don't support! */
+      break;
+
+    case PS_BANDS_COARSE:
+      h->noQmfBandsInHybrid = NO_QMF_BANDS_HYBRID_10;
+      for (k=0; k<h->noQmfBandsInHybrid; k++) {
+        h->aHybridResolution[k] = aHybridResolution10[k];
+      }
+      break;
+
+    default:
+      error = ERROR(CDI, "Invalid hybrid filter bank configuration.");
+      break;
+    }
+  }
+
+  return error;
+}
+
+/*****************************************************************************/
+/* **** FILTERBANK DATA **** */
+
+HANDLE_ERROR_INFO FDKsbrEnc_CreateHybridData(HANDLE_PS_HYBRID_DATA *phHybData,
+                                   INT ch)
+{
+  HANDLE_ERROR_INFO error = noError;
+  int k;
+
+  HANDLE_PS_HYBRID_DATA hHybData = GetRam_HybData(ch);
+  if (hHybData==NULL) {
+    error = 1;
+    goto bail;
+  }
+
+  FDKmemclear(hHybData, sizeof(PS_HYBRID_DATA));
+
+  hHybData->rHybData[0] = GetRam_PsRhyb(ch);
+  hHybData->iHybData[0] = GetRam_PsIhyb(ch);
+  if ( (hHybData->rHybData[0]==NULL) || (hHybData->iHybData[0]==NULL) ) {
+    error = 1;
+    goto bail;
+  }
+
+
+
+  for (k=1; k<(HYBRID_FRAMESIZE+HYBRID_WRITEOFFSET); k++) {
+    hHybData->rHybData[k] = hHybData->rHybData[0] + (k*HYBRID_NUM_BANDS);
+    hHybData->iHybData[k] = hHybData->iHybData[0] + (k*HYBRID_NUM_BANDS);
+  }
+
+bail:
+  *phHybData = hHybData;
+  return error;
+}
+
+
+HANDLE_ERROR_INFO FDKsbrEnc_InitHybridData(HANDLE_PS_HYBRID_DATA hHybData,
+                                   HANDLE_PS_HYBRID_CONFIG  hHybConfig,
+                                   INT frameSize)
+{
+  HANDLE_ERROR_INFO error = noError;
+  INT nHybridBands = 0;
+  INT k = 0;
+  INT noBands = 0;
+  const INT *hybridRes = NULL;
+
+  if (hHybConfig != NULL) {
+    noBands = hHybConfig->noQmfBandsInHybrid;
+    hybridRes = hHybConfig->aHybridResolution;
+  }
+
+  for (k=0; k<noBands; k++) {
+    nHybridBands += (hybridRes[k] & HYBRID_INVERSE_MASK);
+  }
+  FDK_ASSERT (HYBRID_NUM_BANDS>=nHybridBands);
+
+  hHybData->hybDataReadOffset = HYBRID_DATA_READ_OFFSET;
+  hHybData->hybDataWriteOffset = HYBRID_WRITEOFFSET;
+
+  for (k=0; k<(HYBRID_FRAMESIZE+HYBRID_WRITEOFFSET); k++) {
+    FDKmemclear(hHybData->rHybData[k], sizeof(FIXP_QMF)*HYBRID_NUM_BANDS);
+    FDKmemclear(hHybData->iHybData[k], sizeof(FIXP_QMF)*HYBRID_NUM_BANDS);
+  }
+
+  hHybData->frameSize       = frameSize;
+  hHybData->nHybridBands    = nHybridBands;
+  hHybData->nHybridQmfBands = noBands;
+
+  /* store hybrid resoltion in hybrid data handle */
+  FDK_ASSERT (HYBRID_MAX_QMF_BANDS>=hHybData->nHybridQmfBands);
+  for(k = 0; k<hHybData->nHybridQmfBands; k++){
+    hHybData->nHybridResolution[k] = (hybridRes[k] & HYBRID_INVERSE_MASK);
+  }
+
+  return error;
+}
+
+HANDLE_ERROR_INFO FDKsbrEnc_DestroyHybridData(HANDLE_PS_HYBRID_DATA* phHybData)
+{
+  HANDLE_PS_HYBRID_DATA hHybData = *phHybData;
+
+  if (hHybData!=NULL) {
+    FreeRam_PsRhyb(&hHybData->rHybData[0]);
+    FreeRam_PsIhyb(&hHybData->iHybData[0]);
+    FreeRam_HybData(phHybData);
+  }
+
+  return noError;
+}
+
+/*** Access functions ***/
+
+/* return hybrid band resolution of qmf band 'qmfBand' */
+INT FDKsbrEnc_GetHybridResolution(HANDLE_PS_HYBRID_DATA h, INT qmfBand){
+
+  INT nHybridResolution = 0;
+
+  if(h->nHybridResolution){
+    nHybridResolution = h->nHybridResolution[qmfBand];
+  }
+
+  return nHybridResolution;
+}
+
+/*****************************************************************************/
+/* **** FILTERBANK **** */
+
+/*
+   2 channel filter
+   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);
+
+*/
+
+static void dualChannelFiltering(const FIXP_QMF *RESTRICT pQmfReal,
+                                 const FIXP_QMF *RESTRICT pQmfImag,
+                                 FIXP_QMF **RESTRICT mHybridReal,
+                                 FIXP_QMF **RESTRICT mHybridImag,
+                                 INT nSamples)
+{
+  INT i;
+
+  for(i = 0; i < nSamples; i++) {
+    FIXP_DBL  r1, r3, r5, r6;
+    FIXP_DBL  i1, i3, i5, i6;
+
+    /* symmetric filter coefficients
+       scaleValue same as used in eightChannelFiltering (HYBRID_SCALE = 4)
+    */
+    r1 = fMultDiv2(p2_13_20[1], (FIXP_QMF)((pQmfReal[1+i]>>1) + (pQmfReal[11+i]>>1)) ) >> 2;
+    r3 = fMultDiv2(p2_13_20[3], (FIXP_QMF)((pQmfReal[3+i]>>1) + (pQmfReal[ 9+i]>>1)) ) >> 2;
+    r5 = fMultDiv2(p2_13_20[5], (FIXP_QMF)((pQmfReal[5+i]>>1) + (pQmfReal[ 7+i]>>1)) ) >> 2;
+    r6 = fMultDiv2(p2_13_20[6], (FIXP_QMF) (pQmfReal[6+i]>>1) ) >> 2;
+
+    i1 = fMultDiv2(p2_13_20[1], (FIXP_QMF)((pQmfImag[1+i]>>1) + (pQmfImag[11+i]>>1)) ) >> 2;
+    i3 = fMultDiv2(p2_13_20[3], (FIXP_QMF)((pQmfImag[3+i]>>1) + (pQmfImag[ 9+i]>>1)) ) >> 2;
+    i5 = fMultDiv2(p2_13_20[5], (FIXP_QMF)((pQmfImag[5+i]>>1) + (pQmfImag[ 7+i]>>1)) ) >> 2;
+    i6 = fMultDiv2(p2_13_20[6], (FIXP_QMF) (pQmfImag[6+i]>>1) ) >> 2;
+
+    mHybridReal[i][0] = FX_DBL2FX_QMF(r1 + r3 + r5 + r6);
+    mHybridImag[i][0] = FX_DBL2FX_QMF(i1 + i3 + i5 + i6);
+
+    mHybridReal[i][1] = FX_DBL2FX_QMF(- r1 - r3 - r5 + r6);
+    mHybridImag[i][1] = FX_DBL2FX_QMF(- i1 - i3 - i5 + i6);
+  }
+}
+
+/*
+   8 channel filter
+
+   Implementation using a FFT of length 8
+
+   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)  |                                |
+
+*/
+
+static const FIXP_DBL  cr[13] =
+{  cos6Pi_8, cos5Pi_8, cos4Pi_8,
+   cos3Pi_8, cos2Pi_8, cos1Pi_8,
+   cos0Pi_8,
+   cos1Pi_8, cos2Pi_8, cos3Pi_8,
+   cos4Pi_8, cos5Pi_8, cos6Pi_8
+};
+
+static const FIXP_DBL  ci[13] =
+{
+  sin6Pi_8, sin5Pi_8, sin4Pi_8,
+  sin3Pi_8, sin2Pi_8, sin1Pi_8,
+  sin0Pi_8,
+  -sin1Pi_8,  -sin2Pi_8,  -sin3Pi_8,
+  -sin4Pi_8,  -sin5Pi_8,  -sin6Pi_8
+};
+
+
+static void eightChannelFiltering(const FIXP_QMF *pQmfReal,
+                                  const FIXP_QMF *pQmfImag,
+                                  FIXP_DBL *fft,
+                                  FIXP_QMF **mHybridReal,
+                                  FIXP_QMF **mHybridImag,
+                                  INT nSamples,
+                                  const FIXP_DBL *p)
+{
+  INT i, bin;
+  for(i = 0; i < nSamples; i++) {
+    /* pre twiddeling
+       scaling 4 =  2 (fMultDiv2) + 2 (dit_fft) scaling (HYBRID_SCALE = 4)
+    */
+    fft[FFT_IDX_R(0)] = fMultDiv2(p[6],  fMultSubDiv2(fMultDiv2(cr[6], pQmfReal[6+i]), ci[6], pQmfImag[6+i]));
+    fft[FFT_IDX_I(0)] = fMultDiv2(p[6],  fMultAddDiv2(fMultDiv2(ci[6], pQmfReal[6+i]), cr[6], pQmfImag[6+i]));
+
+    fft[FFT_IDX_R(1)] = fMultDiv2(p[7],  fMultSubDiv2(fMultDiv2(cr[7], pQmfReal[7+i]), ci[7], pQmfImag[7+i]));
+    fft[FFT_IDX_I(1)] = fMultDiv2(p[7],  fMultAddDiv2(fMultDiv2(ci[7], pQmfReal[7+i]), cr[7], pQmfImag[7+i]));
+
+    fft[FFT_IDX_R(2)] = ( fMultDiv2(p[ 0], fMultSubDiv2(fMultDiv2(cr[0], pQmfReal[ 0+i]), ci[0], pQmfImag[ 0+i]))+
+                          fMultDiv2(p[ 8], fMultSubDiv2(fMultDiv2(cr[8], pQmfReal[ 8+i]), ci[8], pQmfImag[ 8+i])) );
+    fft[FFT_IDX_I(2)] = ( fMultDiv2(p[ 0], fMultAddDiv2(fMultDiv2(ci[0], pQmfReal[ 0+i]), cr[0], pQmfImag[ 0+i]))+
+                          fMultDiv2(p[ 8], fMultAddDiv2(fMultDiv2(ci[8], pQmfReal[ 8+i]), cr[8], pQmfImag[ 8+i])) );
+
+    fft[FFT_IDX_R(3)] = ( fMultDiv2(p[ 1], fMultSubDiv2(fMultDiv2(cr[1], pQmfReal[ 1+i]), ci[1], pQmfImag[ 1+i]))+
+                          fMultDiv2(p[ 9], fMultSubDiv2(fMultDiv2(cr[9], pQmfReal[ 9+i]), ci[9], pQmfImag[ 9+i])) );
+    fft[FFT_IDX_I(3)] = ( fMultDiv2(p[ 1], fMultAddDiv2(fMultDiv2(ci[1], pQmfReal[ 1+i]), cr[1], pQmfImag[ 1+i]))+
+                          fMultDiv2(p[ 9], fMultAddDiv2(fMultDiv2(ci[9], pQmfReal[ 9+i]), cr[9], pQmfImag[ 9+i])) );
+
+    fft[FFT_IDX_R(4)] = ( fMultDiv2(p[ 2], fMultSubDiv2( fMultDiv2(cr[2], pQmfReal[ 2+i]), ci[2], pQmfImag[ 2+i]))+
+                          fMultDiv2(p[10], fMultSubDiv2(fMultDiv2(cr[10], pQmfReal[10+i]), ci[10], pQmfImag[10+i])) );
+    fft[FFT_IDX_I(4)] = ( fMultDiv2(p[ 2], fMultAddDiv2( fMultDiv2(ci[2], pQmfReal[ 2+i]), cr[2], pQmfImag[ 2+i]))+
+                          fMultDiv2(p[10], fMultAddDiv2(fMultDiv2(ci[10], pQmfReal[10+i]), cr[10], pQmfImag[10+i])) );
+
+    fft[FFT_IDX_R(5)] = ( fMultDiv2(p[ 3], fMultSubDiv2( fMultDiv2(cr[3], pQmfReal[ 3+i]), ci[3], pQmfImag[ 3+i]))+
+                          fMultDiv2(p[11], fMultSubDiv2(fMultDiv2(cr[11], pQmfReal[11+i]), ci[11], pQmfImag[11+i])) );
+    fft[FFT_IDX_I(5)] = ( fMultDiv2(p[ 3], fMultAddDiv2( fMultDiv2(ci[3], pQmfReal[ 3+i]), cr[3], pQmfImag[ 3+i]))+
+                          fMultDiv2(p[11], fMultAddDiv2(fMultDiv2(ci[11], pQmfReal[11+i]), cr[11], pQmfImag[11+i])) );
+
+    fft[FFT_IDX_R(6)] = ( fMultDiv2(p[ 4], fMultSubDiv2( fMultDiv2(cr[4], pQmfReal[ 4+i]), ci[4], pQmfImag[ 4+i]))+
+                          fMultDiv2(p[12], fMultSubDiv2(fMultDiv2(cr[12], pQmfReal[12+i]), ci[12], pQmfImag[12+i])) );
+    fft[FFT_IDX_I(6)] = ( fMultDiv2(p[ 4], fMultAddDiv2( fMultDiv2(ci[4], pQmfReal[ 4+i]), cr[4], pQmfImag[ 4+i]))+
+                          fMultDiv2(p[12], fMultAddDiv2(fMultDiv2(ci[12], pQmfReal[12+i]), cr[12], pQmfImag[12+i])) );
+
+    fft[FFT_IDX_R(7)] = fMultDiv2(p[5], fMultSubDiv2(fMultDiv2(cr[5], pQmfReal[5+i]), ci[5], pQmfImag[5+i]));
+    fft[FFT_IDX_I(7)] = fMultDiv2(p[5], fMultAddDiv2(fMultDiv2(ci[5], pQmfReal[5+i]), cr[5], pQmfImag[5+i]));
+
+    /* fft modulation */
+    fft_8(fft);
+
+    /* resort fft data INTo output array*/
+    for(bin=0; bin<8;bin++ ) {
+      mHybridReal[i][bin] = FX_DBL2FX_QMF(fft[FFT_IDX_R(bin)]);
+      mHybridImag[i][bin] = FX_DBL2FX_QMF(fft[FFT_IDX_I(bin)]);
+    }
+  }
+}
+
+/**************************************************************************//**
+HybridAnalysis
+******************************************************************************/
+
+HANDLE_ERROR_INFO
+HybridAnalysis ( HANDLE_PS_HYBRID       hHybrid,       /*!< Handle to HYBRID struct. */
+                 FIXP_QMF *const *const mQmfReal,      /*!< The real part of the QMF-matrix.  */
+                 FIXP_QMF *const *const mQmfImag,      /*!< The imaginary part of the QMF-matrix. */
+                 SCHAR                  sf_fixpQmf,    /*!< Qmf scale factor */
+                 FIXP_QMF             **mHybridReal,   /*!< The real part of the hybrid-matrix.  */
+                 FIXP_QMF             **mHybridImag,   /*!< The imaginary part of the hybrid-matrix.  */
+                 SCHAR                 *sf_fixpHybrid) /*!< Hybrid scale factor */
+{
+  HANDLE_ERROR_INFO error = noError;
+  INT         n, band;
+  INT         hybridRes;
+  INT         chOffset = 0;
+  /* INT         usedStereoBands   = hHybrid->mode;  */   /*!< indicates which 8 band filter to use */
+  INT         frameSize         = hHybrid->frameSize;
+  INT         hybridFilterDelay = hHybrid->hybridFilterDelay;
+
+  for(band = 0; band < hHybrid->nQmfBands; band++) { /* loop all qmf bands */
+
+    if(error == noError){
+      hybridRes = hHybrid->pResolution[band];
+
+      /* Create working buffer. */
+      /* Copy stored samples to working buffer. */
+      FDKmemcpy(hHybrid->pWorkReal, hHybrid->mQmfBufferReal[band],
+                 hHybrid->qmfBufferMove * sizeof(FIXP_QMF));
+      FDKmemcpy(hHybrid->pWorkImag, hHybrid->mQmfBufferImag[band],
+                 hHybrid->qmfBufferMove * sizeof(FIXP_QMF));
+
+      /* Append new samples to working buffer. */
+      for(n = 0; n < frameSize; n++) {
+        hHybrid->pWorkReal [hHybrid->qmfBufferMove + n] = mQmfReal [n + hybridFilterDelay] [band];
+        hHybrid->pWorkImag [hHybrid->qmfBufferMove + n] = mQmfImag [n + hybridFilterDelay] [band];
+      }
+
+      /* Store samples for next frame. */
+      FDKmemcpy(hHybrid->mQmfBufferReal[band], hHybrid->pWorkReal + frameSize,
+                 hHybrid->qmfBufferMove * sizeof(FIXP_QMF));
+      FDKmemcpy(hHybrid->mQmfBufferImag[band], hHybrid->pWorkImag + frameSize,
+                 hHybrid->qmfBufferMove * sizeof(FIXP_QMF));
+
+
+      switch(hybridRes) {
+      case HYBRID_2_REAL:
+        dualChannelFiltering( hHybrid->pWorkReal,
+                              hHybrid->pWorkImag,
+                              hHybrid->mTempReal,
+                              hHybrid->mTempImag,
+                              frameSize);
+
+        /* copy data to output buffer */
+        for(n = 0; n < frameSize; n++) {
+          FDKmemcpy(&mHybridReal[n][chOffset], hHybrid->mTempReal[n],
+                     (INT)(hybridRes & HYBRID_INVERSE_MASK)*sizeof(FIXP_QMF));
+          FDKmemcpy(&mHybridImag[n][chOffset], hHybrid->mTempImag[n],
+                     (INT)(hybridRes & HYBRID_INVERSE_MASK)*sizeof(FIXP_QMF));
+        }
+        break;
+
+      case HYBRID_2_REAL | HYBRID_INVERSE_ORDER:
+        dualChannelFiltering( hHybrid->pWorkReal,
+                              hHybrid->pWorkImag,
+                              hHybrid->mTempReal,
+                              hHybrid->mTempImag,
+                              frameSize);
+
+        /* copy and resort data */
+        for ( n = 0; n < frameSize; n++ )
+          {
+            mHybridReal[n][chOffset + 0] = hHybrid->mTempReal[n][1] ;
+            mHybridReal[n][chOffset + 1] = hHybrid->mTempReal[n][0] ;
+            mHybridImag[n][chOffset + 0] = hHybrid->mTempImag[n][1] ;
+            mHybridImag[n][chOffset + 1] = hHybrid->mTempImag[n][0] ;
+          }
+        break;
+
+      case HYBRID_6_CPLX:
+        eightChannelFiltering( hHybrid->pWorkReal,
+                               hHybrid->pWorkImag,
+                               hHybrid->fft,
+                               hHybrid->mTempReal,
+                               hHybrid->mTempImag,
+                               frameSize,
+                               /*(usedStereoBands==PS_BANDS_FINE)?p8_13_34:*/p8_13_20);
+
+        /* do the shuffle */
+        for ( n = 0; n < frameSize; n++ )
+          {
+            /* add data ... */
+            hHybrid->mTempReal[n][2] += hHybrid->mTempReal[n][5];
+            hHybrid->mTempImag[n][2] += hHybrid->mTempImag[n][5];
+            hHybrid->mTempReal[n][3] += hHybrid->mTempReal[n][4];
+            hHybrid->mTempImag[n][3] += hHybrid->mTempImag[n][4];
+
+            /* shuffle and copy to output buffer */
+            mHybridReal[n][chOffset + 0] = hHybrid->mTempReal[n][6] ;
+            mHybridReal[n][chOffset + 1] = hHybrid->mTempReal[n][7] ;
+            mHybridReal[n][chOffset + 2] = hHybrid->mTempReal[n][0] ;
+            mHybridReal[n][chOffset + 3] = hHybrid->mTempReal[n][1] ;
+            mHybridReal[n][chOffset + 4] = hHybrid->mTempReal[n][2] ;
+            mHybridReal[n][chOffset + 5] = hHybrid->mTempReal[n][3] ;
+
+            mHybridImag[n][chOffset + 0] = hHybrid->mTempImag[n][6] ;
+            mHybridImag[n][chOffset + 1] = hHybrid->mTempImag[n][7] ;
+            mHybridImag[n][chOffset + 2] = hHybrid->mTempImag[n][0] ;
+            mHybridImag[n][chOffset + 3] = hHybrid->mTempImag[n][1] ;
+            mHybridImag[n][chOffset + 4] = hHybrid->mTempImag[n][2] ;
+            mHybridImag[n][chOffset + 5] = hHybrid->mTempImag[n][3] ;
+          }
+        break;
+
+      case HYBRID_8_CPLX:
+        eightChannelFiltering( hHybrid->pWorkReal,
+                               hHybrid->pWorkImag,
+                               hHybrid->fft,
+                               hHybrid->mTempReal,
+                               hHybrid->mTempImag,
+                               frameSize,
+                               /*(usedStereoBands==PS_BANDS_FINE)?p8_13_34:*/p8_13_20);
+
+        /* copy data to output buffer */
+        for(n = 0; n < frameSize; n++) {
+          FDKmemcpy(&mHybridReal[n][chOffset], hHybrid->mTempReal[n],
+                     (INT)(hybridRes & HYBRID_INVERSE_MASK)*sizeof(FIXP_QMF));
+          FDKmemcpy(&mHybridImag[n][chOffset], hHybrid->mTempImag[n],
+                     (INT)(hybridRes & HYBRID_INVERSE_MASK)*sizeof(FIXP_QMF));
+        }
+        break;
+
+      default:
+        error = ERROR(CDI, "Invalid filter bank configuration.");
+        break;
+      }
+      /* prepare next run by incresing chOffset */
+      chOffset += hybridRes & HYBRID_INVERSE_MASK;
+    }
+  }
+
+  *sf_fixpHybrid = sf_fixpQmf + HYBRID_SCALE;
+
+  return error;
+}
+
+/**************************************************************************//**
+  FDKsbrEnc_CreateHybridFilterBank
+******************************************************************************/
+HANDLE_ERROR_INFO
+FDKsbrEnc_CreateHybridFilterBank ( HANDLE_PS_HYBRID        *phHybrid,     /*!< Pointer to handle to HYBRID struct.  */
+                                   INT                      ch)           /*!< Current channel */
+{
+  HANDLE_ERROR_INFO  error = noError;
+  INT i;
+  HANDLE_PS_HYBRID hs = GetRam_PsHybrid(ch); /* allocate memory */
+  if (hs==NULL) {
+    error = 1;
+    goto bail;
+  }
+
+  hs->fft = GetRam_PsHybFFT();
+
+  /* alloc working memory */
+  hs->pWorkReal = GetRam_PsHybWkReal();
+  hs->pWorkImag = GetRam_PsHybWkImag();
+
+  if ( (hs->fft==NULL) || (hs->pWorkReal==NULL) || (hs->pWorkImag==NULL) ) {
+    error = 1;
+    goto bail;
+  }
+
+  /* Allocate buffers */
+  for (i = 0; i < HYBRID_FRAMESIZE; i++) {
+    hs->mTempReal[i] = GetRam_PsMtmpReal(i);
+    hs->mTempImag[i] = GetRam_PsMtmpImag(i);
+    if ( (hs->mTempReal[i]==NULL) || (hs->mTempImag[i]==NULL) ) {
+      error = 1;
+      goto bail;
+    }
+  }
+
+bail:
+  *phHybrid = hs;
+  return error;
+}
+
+HANDLE_ERROR_INFO
+FDKsbrEnc_InitHybridFilterBank ( HANDLE_PS_HYBRID         hs,           /*!< Handle to HYBRID struct.  */
+                                 HANDLE_PS_HYBRID_CONFIG  hHybConfig,   /*!< Configuration hanlde for filter bank */
+                                 INT                      frameSize)    /*!< Number of QMF slots */
+{
+  HANDLE_ERROR_INFO  error = noError;
+  INT i;
+  INT maxNoChannels = HYBRID_12_CPLX, noBands;
+  PS_BANDS mode;
+  const INT *RESTRICT pResolution;
+
+  /* filter bank configuration */
+  mode    = hHybConfig->mode;
+  noBands = hHybConfig->noQmfBandsInHybrid;
+  pResolution = hHybConfig->aHybridResolution;
+
+  /* assign resolution, check for valid values */
+  for (i = 0; i < noBands; i++) {
+    if(error == noError){
+      if( pResolution[i] != HYBRID_12_CPLX &&
+          pResolution[i] != HYBRID_8_CPLX &&
+          pResolution[i] != HYBRID_6_CPLX &&
+          pResolution[i] != HYBRID_2_REAL &&
+          pResolution[i] != (HYBRID_2_REAL | HYBRID_INVERSE_ORDER) &&
+          pResolution[i] != HYBRID_4_CPLX ){
+        error = ERROR(CDI, "Invalid filter bank resolution");
+      }
+    }
+    hs->pResolution[i] = pResolution[i];
+    if((pResolution[i] & HYBRID_INVERSE_MASK) > maxNoChannels){
+      maxNoChannels = pResolution[i] & HYBRID_INVERSE_MASK;
+    }
+  }
+  FDK_ASSERT (MAX_HYBRID_RES>=maxNoChannels); /* check size of mTempReal/Imag */
+
+  /* assign parameters */
+  hs->mode              = mode;
+  hs->nQmfBands         = noBands;
+  hs->frameSize         = frameSize;
+  hs->frameSizeInit     = frameSize;
+  hs->qmfBufferMove     = HYBRID_FILTER_LENGTH - 1;
+  hs->hybridFilterDelay = HYBRID_FILTER_LENGTH/2;
+
+  FDK_ASSERT (HYBRID_FRAMESIZE>=hs->frameSize);
+  FDK_ASSERT (QMF_BUFFER_MOVE>=hs->qmfBufferMove);
+
+  return error;
+}
+
+
+/**************************************************************************//**
+   FDKsbrEnc_DeleteHybridFilterBank
+******************************************************************************/
+
+HANDLE_ERROR_INFO
+FDKsbrEnc_DeleteHybridFilterBank ( HANDLE_PS_HYBRID* phHybrid ) /*!< Pointer to handle to HYBRID struct. */
+{
+  int i;
+  HANDLE_PS_HYBRID hHybrid = *phHybrid;
+
+  if (hHybrid!=NULL) {
+    if (hHybrid->fft)
+      FreeRam_PsHybFFT(&hHybrid->fft);
+    if (hHybrid->pWorkReal)
+      FreeRam_PsHybWkReal(&hHybrid->pWorkReal);
+    if (hHybrid->pWorkImag)
+      FreeRam_PsHybWkImag(&hHybrid->pWorkImag);
+
+    for (i = 0; i < HYBRID_FRAMESIZE; i++) {
+      if (hHybrid->mTempReal[i])
+        FreeRam_PsMtmpReal(&hHybrid->mTempReal[i]);
+      if (hHybrid->mTempImag[i])
+      FreeRam_PsMtmpImag(&hHybrid->mTempImag[i]);
+    }
+
+    FreeRam_PsHybrid(phHybrid);
+  }
+
+  return noError;
+}
+
+/*** Access functions ***/
+INT FDKsbrEnc_GetHybridFilterDelay(HANDLE_PS_HYBRID hHybrid){
+
+  return hHybrid->hybridFilterDelay;
+}
+