Fraunhofer AAC codec.

License boilerplate update to follow.

Change-Id: I2810460c11a58b6d148d84673cc031f3685e79b5

1 files changed, 170 insertions, 0 deletions

diff --git a/libAACenc/src/noisedet.cpp b/libAACenc/src/noisedet.cpp
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+/******************************** MPEG Audio Encoder **************************
+
+                     (C) Copyright Fraunhofer IIS (2001)
+                               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.
+
+
+   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.
+
+   $Id$
+
+   Initial author:       M. Lohwasser
+   contents/description: noisedet.c
+                         Routines for Noise Detection
+
+******************************************************************************/
+
+#include "noisedet.h"
+
+#include "aacenc_pns.h"
+#include "pnsparam.h"
+
+
+/*****************************************************************************
+
+    functionname: FDKaacEnc_fuzzyIsSmaller
+    description:  Fuzzy value calculation for "testVal is smaller than refVal"
+    returns:      fuzzy value
+    input:        test and ref Value,
+                  low and high Lim
+    output:       return fuzzy value
+
+*****************************************************************************/
+static FIXP_SGL FDKaacEnc_fuzzyIsSmaller( FIXP_DBL testVal,
+                                FIXP_DBL refVal,
+                                FIXP_DBL loLim,
+                                FIXP_DBL hiLim )
+{
+  if (refVal <= FL2FXCONST_DBL(0.0))
+        return( FL2FXCONST_SGL(0.0f) );
+  else if (testVal >= fMult((hiLim>>1)+(loLim>>1), refVal))
+        return( FL2FXCONST_SGL(0.0f) );
+  else  return( (FIXP_SGL)MAXVAL_SGL );
+}
+
+
+
+/*****************************************************************************
+
+    functionname: FDKaacEnc_noiseDetect
+    description:  detect tonal sfb's; two tests
+                  Powerdistribution:
+                    sfb splittet in four regions,
+                    compare the energy in all sections
+                  PsychTonality:
+                    compare tonality from chaosmeasure with reftonality
+    returns:
+    input:        spectrum of one large mdct
+                  number of sfb's
+                  pointer to offset of sfb's
+                  pointer to noiseFuzzyMeasure (modified)
+                  noiseparams struct
+                  pointer to sfb energies
+                  pointer to tonality calculated in chaosmeasure
+    output:       noiseFuzzy Measure
+
+*****************************************************************************/
+
+void FDKaacEnc_noiseDetect(FIXP_DBL    *RESTRICT mdctSpectrum,
+                 INT         *RESTRICT sfbMaxScaleSpec,
+                 INT          sfbActive,
+                 const INT   *RESTRICT sfbOffset,
+                 FIXP_SGL    *RESTRICT noiseFuzzyMeasure,
+                 NOISEPARAMS *np,
+                 FIXP_SGL    *RESTRICT sfbtonality )
+
+{
+  int    i, k, sfb, sfbWidth;
+  FIXP_SGL fuzzy, fuzzyTotal;
+  FIXP_DBL refVal, testVal;
+
+#define ALL_SFB_TONAL 0
+#define ALL_SFB_NONTONAL 0
+
+  /***** Start detection phase *****/
+  /* Start noise detection for each band based on a number of checks */
+  for (sfb=0; sfb<sfbActive; sfb++) {
+
+    fuzzyTotal = (FIXP_SGL)MAXVAL_SGL;
+    sfbWidth = sfbOffset[sfb+1] - sfbOffset[sfb];
+
+    /* Reset output for lower bands or too small bands */
+    if (sfb < np->startSfb  ||  sfbWidth < np->minSfbWidth) {
+      noiseFuzzyMeasure[sfb] = FL2FXCONST_SGL(0.0f);
+      continue;
+    }
+
+    if ( (np->detectionAlgorithmFlags & USE_POWER_DISTRIBUTION) && (fuzzyTotal > FL2FXCONST_SGL(0.5f)) ) {
+      FIXP_DBL fhelp1, fhelp2, fhelp3, fhelp4, maxVal, minVal;
+      INT leadingBits = fixMax(0,(sfbMaxScaleSpec[sfb] - 3));         /* max sfbWidth = 96/4 ; 2^5=32 => 5/2 = 3 (spc*spc) */
+
+      /*  check power distribution in four regions */
+      fhelp1 = fhelp2 = fhelp3 = fhelp4 = FL2FXCONST_DBL(0.0f);
+      k = sfbWidth >>2;  /* Width of a quarter band */
+
+      for (i=sfbOffset[sfb]; i<sfbOffset[sfb]+k; i++) {
+        fhelp1 = fPow2AddDiv2(fhelp1, mdctSpectrum[i]<<leadingBits);
+        fhelp2 = fPow2AddDiv2(fhelp2, mdctSpectrum[i+k]<<leadingBits);
+        fhelp3 = fPow2AddDiv2(fhelp3, mdctSpectrum[i+2*k]<<leadingBits);
+        fhelp4 = fPow2AddDiv2(fhelp4, mdctSpectrum[i+3*k]<<leadingBits);
+      }
+
+      /* get max into fhelp: */
+      maxVal = fixMax(fhelp1, fhelp2);
+      maxVal = fixMax(maxVal, fhelp3);
+      maxVal = fixMax(maxVal, fhelp4);
+
+      /* get min into fhelp1: */
+      minVal = fixMin(fhelp1, fhelp2);
+      minVal = fixMin(minVal, fhelp3);
+      minVal = fixMin(minVal, fhelp4);
+
+      /* Normalize min and max Val */
+      leadingBits = CountLeadingBits(maxVal);
+      testVal = maxVal << leadingBits;
+      refVal  = minVal << leadingBits;
+
+      /* calculate fuzzy value for power distribution */
+      testVal = fMultDiv2(testVal, np->powDistPSDcurve[sfb]);
+
+      fuzzy = FDKaacEnc_fuzzyIsSmaller(testVal,           /* 1/2 * maxValue * PSDcurve */
+                             refVal,            /* 1   * minValue            */
+                             FL2FXCONST_DBL(0.495),  /* 1/2 * loLim  (0.99f/2)    */
+                             FL2FXCONST_DBL(0.505)); /* 1/2 * hiLim  (1.01f/2)    */
+
+      fuzzyTotal = fixMin(fuzzyTotal, fuzzy);
+    }
+
+    if ( (np->detectionAlgorithmFlags & USE_PSYCH_TONALITY) && (fuzzyTotal > FL2FXCONST_SGL(0.5f)) ) {
+      /* Detection with tonality-value of psych. acoustic (here: 1 is tonal!)*/
+
+      testVal = FX_SGL2FX_DBL(sfbtonality[sfb])>>1;          /* 1/2 * sfbTonality         */
+      refVal  = np->refTonality;
+
+      fuzzy   = FDKaacEnc_fuzzyIsSmaller(testVal,
+                               refVal,
+                               FL2FXCONST_DBL(0.45f),    /* 1/2 * loLim  (0.9f/2)     */
+                               FL2FXCONST_DBL(0.55f));   /* 1/2 * hiLim  (1.1f/2)     */
+
+      fuzzyTotal = fixMin(fuzzyTotal, fuzzy);
+    }
+
+
+    /* Output of final result */
+    noiseFuzzyMeasure[sfb] = fuzzyTotal;
+  }
+}