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, 361 insertions, 0 deletions

diff --git a/fdk-aac/libAACdec/src/aacdec_pns.cpp b/fdk-aac/libAACdec/src/aacdec_pns.cpp
new file mode 100644
index 0000000..432cd4e
--- /dev/null
+++ b/fdk-aac/libAACdec/src/aacdec_pns.cpp
@@ -0,0 +1,361 @@
+/* -----------------------------------------------------------------------------
+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 decoder library ******************************
+
+   Author(s):   Josef Hoepfl
+
+   Description: perceptual noise substitution tool
+
+*******************************************************************************/
+
+#include "aacdec_pns.h"
+
+#include "aac_ram.h"
+#include "aac_rom.h"
+#include "channelinfo.h"
+#include "block.h"
+#include "FDK_bitstream.h"
+
+#include "genericStds.h"
+
+#define NOISE_OFFSET 90 /* cf. ISO 14496-3 p. 175 */
+
+/*!
+  \brief Reset InterChannel and PNS data
+
+  The function resets the InterChannel and PNS data
+*/
+void CPns_ResetData(CPnsData *pPnsData,
+                    CPnsInterChannelData *pPnsInterChannelData) {
+  FDK_ASSERT(pPnsData != NULL);
+  FDK_ASSERT(pPnsInterChannelData != NULL);
+  /* Assign pointer always, since pPnsData is not persistent data */
+  pPnsData->pPnsInterChannelData = pPnsInterChannelData;
+  pPnsData->PnsActive = 0;
+  pPnsData->CurrentEnergy = 0;
+
+  FDKmemclear(pPnsData->pnsUsed, (8 * 16) * sizeof(UCHAR));
+  FDKmemclear(pPnsInterChannelData->correlated, (8 * 16) * sizeof(UCHAR));
+}
+
+/*!
+  \brief Update PNS noise generator state.
+
+  The function sets the seed for PNS noise generation.
+  It can be used to link two or more channels in terms of PNS.
+*/
+void CPns_UpdateNoiseState(CPnsData *pPnsData, INT *currentSeed,
+                           INT *randomSeed) {
+  /* use pointer because seed has to be
+     same, left and right channel ! */
+  pPnsData->currentSeed = currentSeed;
+  pPnsData->randomSeed = randomSeed;
+}
+
+/*!
+  \brief Indicates if PNS is used
+
+  The function returns a value indicating whether PNS is used or not
+  acordding to the noise energy
+
+  \return  PNS used
+*/
+int CPns_IsPnsUsed(const CPnsData *pPnsData, const int group, const int band) {
+  unsigned pns_band = group * 16 + band;
+
+  return pPnsData->pnsUsed[pns_band] & (UCHAR)1;
+}
+
+/*!
+  \brief Set correlation
+
+  The function activates the noise correlation between the channel pair
+*/
+void CPns_SetCorrelation(CPnsData *pPnsData, const int group, const int band,
+                         const int outofphase) {
+  CPnsInterChannelData *pInterChannelData = pPnsData->pPnsInterChannelData;
+  unsigned pns_band = group * 16 + band;
+
+  pInterChannelData->correlated[pns_band] = (outofphase) ? 3 : 1;
+}
+
+/*!
+  \brief Indicates if correlation is used
+
+  The function indicates if the noise correlation between the channel pair
+  is activated
+
+  \return  PNS is correlated
+*/
+static int CPns_IsCorrelated(const CPnsData *pPnsData, const int group,
+                             const int band) {
+  CPnsInterChannelData *pInterChannelData = pPnsData->pPnsInterChannelData;
+  unsigned pns_band = group * 16 + band;
+
+  return (pInterChannelData->correlated[pns_band] & 0x01) ? 1 : 0;
+}
+
+/*!
+  \brief Indicates if correlated out of phase mode is used.
+
+  The function indicates if the noise correlation between the channel pair
+  is activated in out-of-phase mode.
+
+  \return  PNS is out-of-phase
+*/
+static int CPns_IsOutOfPhase(const CPnsData *pPnsData, const int group,
+                             const int band) {
+  CPnsInterChannelData *pInterChannelData = pPnsData->pPnsInterChannelData;
+  unsigned pns_band = group * 16 + band;
+
+  return (pInterChannelData->correlated[pns_band] & 0x02) ? 1 : 0;
+}
+
+/*!
+  \brief Read PNS information
+
+  The function reads the PNS information from the bitstream
+*/
+void CPns_Read(CPnsData *pPnsData, HANDLE_FDK_BITSTREAM bs,
+               const CodeBookDescription *hcb, SHORT *pScaleFactor,
+               UCHAR global_gain, int band, int group /* = 0 */) {
+  int delta;
+  UINT pns_band = group * 16 + band;
+
+  if (pPnsData->PnsActive) {
+    /* Next PNS band case */
+    delta = CBlock_DecodeHuffmanWord(bs, hcb) - 60;
+  } else {
+    /* First PNS band case */
+    int noiseStartValue = FDKreadBits(bs, 9);
+
+    delta = noiseStartValue - 256;
+    pPnsData->PnsActive = 1;
+    pPnsData->CurrentEnergy = global_gain - NOISE_OFFSET;
+  }
+
+  pPnsData->CurrentEnergy += delta;
+  pScaleFactor[pns_band] = pPnsData->CurrentEnergy;
+
+  pPnsData->pnsUsed[pns_band] = 1;
+}
+
+/**
+ * \brief Generate a vector of noise of given length. The noise values are
+ *        scaled in order to yield a noise energy of 1.0
+ * \param spec pointer to were the noise values will be written to.
+ * \param size amount of noise values to be generated.
+ * \param pRandomState pointer to the state of the random generator being used.
+ * \return exponent of generated noise vector.
+ */
+static int GenerateRandomVector(FIXP_DBL *RESTRICT spec, int size,
+                                int *pRandomState) {
+  int i, invNrg_e = 0, nrg_e = 0;
+  FIXP_DBL invNrg_m, nrg_m = FL2FXCONST_DBL(0.0f);
+  FIXP_DBL *RESTRICT ptr = spec;
+  int randomState = *pRandomState;
+
+#define GEN_NOISE_NRG_SCALE 7
+
+  /* Generate noise and calculate energy. */
+  for (i = 0; i < size; i++) {
+    randomState =
+        (((INT64)1664525 * randomState) + (INT64)1013904223) & 0xFFFFFFFF;
+    nrg_m = fPow2AddDiv2(nrg_m, (FIXP_DBL)randomState >> GEN_NOISE_NRG_SCALE);
+    *ptr++ = (FIXP_DBL)randomState;
+  }
+  nrg_e = GEN_NOISE_NRG_SCALE * 2 + 1;
+
+  /* weight noise with = 1 / sqrt_nrg; */
+  invNrg_m = invSqrtNorm2(nrg_m << 1, &invNrg_e);
+  invNrg_e += -((nrg_e - 1) >> 1);
+
+  for (i = size; i--;) {
+    spec[i] = fMult(spec[i], invNrg_m);
+  }
+
+  /* Store random state */
+  *pRandomState = randomState;
+
+  return invNrg_e;
+}
+
+static void ScaleBand(FIXP_DBL *RESTRICT spec, int size, int scaleFactor,
+                      int specScale, int noise_e, int out_of_phase) {
+  int i, shift, sfExponent;
+  FIXP_DBL sfMatissa;
+
+  /* Get gain from scale factor value = 2^(scaleFactor * 0.25) */
+  sfMatissa = MantissaTable[scaleFactor & 0x03][0];
+  /* sfExponent = (scaleFactor >> 2) + ExponentTable[scaleFactor & 0x03][0]; */
+  /* Note:  ExponentTable[scaleFactor & 0x03][0] is always 1. */
+  sfExponent = (scaleFactor >> 2) + 1;
+
+  if (out_of_phase != 0) {
+    sfMatissa = -sfMatissa;
+  }
+
+  /* +1 because of fMultDiv2 below. */
+  shift = sfExponent - specScale + 1 + noise_e;
+
+  /* Apply gain to noise values */
+  if (shift >= 0) {
+    shift = fixMin(shift, DFRACT_BITS - 1);
+    for (i = size; i-- != 0;) {
+      spec[i] = fMultDiv2(spec[i], sfMatissa) << shift;
+    }
+  } else {
+    shift = fixMin(-shift, DFRACT_BITS - 1);
+    for (i = size; i-- != 0;) {
+      spec[i] = fMultDiv2(spec[i], sfMatissa) >> shift;
+    }
+  }
+}
+
+/*!
+  \brief Apply PNS
+
+  The function applies PNS (i.e. it generates noise) on the bands
+  flagged as noisy bands
+
+*/
+void CPns_Apply(const CPnsData *pPnsData, const CIcsInfo *pIcsInfo,
+                SPECTRAL_PTR pSpectrum, const SHORT *pSpecScale,
+                const SHORT *pScaleFactor,
+                const SamplingRateInfo *pSamplingRateInfo,
+                const INT granuleLength, const int channel) {
+  if (pPnsData->PnsActive) {
+    const short *BandOffsets =
+        GetScaleFactorBandOffsets(pIcsInfo, pSamplingRateInfo);
+
+    int ScaleFactorBandsTransmitted = GetScaleFactorBandsTransmitted(pIcsInfo);
+
+    for (int window = 0, group = 0; group < GetWindowGroups(pIcsInfo);
+         group++) {
+      for (int groupwin = 0; groupwin < GetWindowGroupLength(pIcsInfo, group);
+           groupwin++, window++) {
+        FIXP_DBL *spectrum = SPEC(pSpectrum, window, granuleLength);
+
+        for (int band = 0; band < ScaleFactorBandsTransmitted; band++) {
+          if (CPns_IsPnsUsed(pPnsData, group, band)) {
+            UINT pns_band = window * 16 + band;
+
+            int bandWidth = BandOffsets[band + 1] - BandOffsets[band];
+            int noise_e;
+
+            FDK_ASSERT(bandWidth >= 0);
+
+            if (channel > 0 && CPns_IsCorrelated(pPnsData, group, band)) {
+              noise_e =
+                  GenerateRandomVector(spectrum + BandOffsets[band], bandWidth,
+                                       &pPnsData->randomSeed[pns_band]);
+            } else {
+              pPnsData->randomSeed[pns_band] = *pPnsData->currentSeed;
+
+              noise_e = GenerateRandomVector(spectrum + BandOffsets[band],
+                                             bandWidth, pPnsData->currentSeed);
+            }
+
+            int outOfPhase = CPns_IsOutOfPhase(pPnsData, group, band);
+
+            ScaleBand(spectrum + BandOffsets[band], bandWidth,
+                      pScaleFactor[group * 16 + band], pSpecScale[window],
+                      noise_e, outOfPhase);
+          }
+        }
+      }
+    }
+  }
+}