Include patched FDK-AAC in the repository

The initial idea was to get the DAB+ patch into upstream, but since
that follows the android source releases, there is no place for a custom
DAB+ patch there.

So instead of having to maintain a patched fdk-aac that has to have the
same .so version as the distribution package on which it is installed,
we prefer having a separate fdk-aac-dab library to avoid collision.

At that point, there's no reason to keep fdk-aac in a separate
repository, as odr-audioenc is the only tool that needs DAB+ encoding
support. Including it here simplifies installation, and makes it
consistent with toolame-dab, also shipped in this repository.

DAB+ decoding support (needed by ODR-SourceCompanion, dablin, etisnoop,
welle.io and others) can be done using upstream FDK-AAC.

1 files changed, 235 insertions, 0 deletions

diff --git a/fdk-aac/libAACenc/src/noisedet.cpp b/fdk-aac/libAACenc/src/noisedet.cpp
new file mode 100644
index 0000000..c984304
--- /dev/null
+++ b/fdk-aac/libAACenc/src/noisedet.cpp
@@ -0,0 +1,235 @@
+/* -----------------------------------------------------------------------------
+Software License for The Fraunhofer FDK AAC Codec Library for Android
+
+© Copyright  1995 - 2018 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
+----------------------------------------------------------------------------- */
+
+/**************************** AAC encoder library ******************************
+
+   Author(s):   M. Lohwasser
+
+   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;
+
+  /***** 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;
+  }
+}