Fraunhofer AAC codec.

License boilerplate update to follow.

Change-Id: I2810460c11a58b6d148d84673cc031f3685e79b5

1 files changed, 450 insertions, 0 deletions

diff --git a/libSBRdec/src/sbrdec_drc.cpp b/libSBRdec/src/sbrdec_drc.cpp
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+/*****************************  MPEG-4 AAC Decoder  **************************
+
+                        (C) Copyright Fraunhofer IIS (2004)
+                               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.
+
+
+   $Id$
+   Author(s):   Christian Griebel
+   Description: Dynamic range control (DRC) decoder tool for SBR
+
+   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 "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;
+}
+