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, 218 insertions, 0 deletions

diff --git a/fdk-aac/libFDK/include/FDK_lpc.h b/fdk-aac/libFDK/include/FDK_lpc.h
new file mode 100644
index 0000000..851dd1f
--- /dev/null
+++ b/fdk-aac/libFDK/include/FDK_lpc.h
@@ -0,0 +1,218 @@
+/* -----------------------------------------------------------------------------
+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
+----------------------------------------------------------------------------- */
+
+/******************* Library for basic calculation routines ********************
+
+   Author(s):   Manuel Jander
+
+   Description: LPC related functions
+
+*******************************************************************************/
+
+#ifndef FDK_LPC_H
+#define FDK_LPC_H
+
+#include "common_fix.h"
+
+#define LPC_MAX_ORDER 24
+
+/*
+ * Experimental solution for lattice filter substitution.
+ * LPC_SYNTHESIS_IIR macro must be activated in aacdec_tns.cpp.
+ * When LPC_SYNTHESIS_IIR enabled, there will be a substitution of the default
+ * lpc synthesis lattice filter by an IIR synthesis filter (with a conversionof
+ * the filter coefs). LPC_TNS related macros are intended to implement the data
+ * types used by the CLpc_Synthesis variant which is used for this solution.
+ * */
+
+/* #define LPC_TNS_LOWER_PRECISION */
+
+typedef FIXP_DBL FIXP_LPC_TNS;
+#define FX_DBL2FX_LPC_TNS(x) (x)
+#define FX_DBL2FXCONST_LPC_TNS(x) (x)
+#define FX_LPC_TNS2FX_DBL(x) (x)
+#define FL2FXCONST_LPC_TNS(val) FL2FXCONST_DBL(val)
+#define MAXVAL_LPC_TNS MAXVAL_DBL
+
+typedef FIXP_SGL FIXP_LPC;
+#define FX_DBL2FX_LPC(x) FX_DBL2FX_SGL((FIXP_DBL)(x))
+#define FX_DBL2FXCONST_LPC(x) FX_DBL2FXCONST_SGL(x)
+#define FX_LPC2FX_DBL(x) FX_SGL2FX_DBL(x)
+#define FL2FXCONST_LPC(val) FL2FXCONST_SGL(val)
+#define MAXVAL_LPC MAXVAL_SGL
+
+/**
+ * \brief Obtain residual signal through LPC analysis.
+ * \param signal pointer to buffer holding signal to be analysed. Residual is
+ * returned there (in place)
+ * \param signal_size the size of the input data in pData
+ * \param lpcCoeff_m the LPC filter coefficient mantissas
+ * \param lpcCoeff_e the LPC filter coefficient exponent
+ * \param order the LPC filter order (size of coeff)
+ * \param filtState Pointer to state buffer of size order
+ * \param filtStateIndex pointer to state index storage
+ */
+void CLpc_Analysis(FIXP_DBL signal[], const int signal_size,
+                   const FIXP_LPC lpcCoeff_m[], const int lpcCoeff_e,
+                   const int order, FIXP_DBL *filtState, int *filtStateIndex);
+
+/**
+ * \brief Synthesize signal fom residual through LPC synthesis, using LP
+ * coefficients.
+ * \param signal pointer to buffer holding the residual signal. The synthesis is
+ * returned there (in place)
+ * \param signal_size the size of the input data in pData
+ * \param inc buffer traversal increment for signal
+ * \param coeff the LPC filter coefficients
+ * \param coeff_e exponent of coeff
+ * \param order the LPC filter order (size of coeff)
+ * \param state state buffer of size LPC_MAX_ORDER
+ * \param pStateIndex pointer to state index storage
+ */
+void CLpc_Synthesis(FIXP_DBL *signal, const int signal_size, const int signal_e,
+                    const int inc, const FIXP_LPC_TNS *lpcCoeff_m,
+                    const int lpcCoeff_e, const int order, FIXP_DBL *state,
+                    int *pStateIndex);
+void CLpc_Synthesis(FIXP_DBL *signal, const int signal_size, const int signal_e,
+                    const int inc, const FIXP_LPC coeff[], const int coeff_e,
+                    const int order, FIXP_DBL *filtState, int *pStateIndex);
+
+/**
+ * \brief Synthesize signal fom residual through LPC synthesis, using ParCor
+ * coefficients. The algorithm assumes a filter gain of max 1.0. If the filter
+ * gain is higher, this must be accounted into the values of signal_e
+ * and/or signal_e_out to avoid overflows.
+ * \param signal pointer to buffer holding the residual signal. The synthesis is
+ * returned there (in place)
+ * \param signal_size the size of the input data in pData
+ * \param inc buffer traversal increment for signal
+ * \param coeff the LPC filter coefficients
+ * \param coeff_e exponent of coeff
+ * \param order the LPC filter order (size of coeff)
+ * \param state state buffer of size LPC_MAX_ORDER
+ */
+void CLpc_SynthesisLattice(FIXP_DBL *signal, const int signal_size,
+                           const int signal_e, const int signal_e_out,
+                           const int inc, const FIXP_SGL *coeff,
+                           const int order, FIXP_DBL *state);
+
+void CLpc_SynthesisLattice(FIXP_DBL *RESTRICT signal, const int signal_size,
+                           const int signal_e, const int signal_e_out,
+                           const int inc, const FIXP_DBL *RESTRICT coeff,
+                           const int order, FIXP_DBL *RESTRICT state);
+
+/**
+ * \brief
+ */
+INT CLpc_ParcorToLpc(const FIXP_LPC_TNS reflCoeff[], FIXP_LPC_TNS LpcCoeff[],
+                     INT numOfCoeff, FIXP_DBL workBuffer[]);
+INT CLpc_ParcorToLpc(const FIXP_LPC reflCoeff[], FIXP_LPC LpcCoeff[],
+                     const int numOfCoeff, FIXP_DBL workBuffer[]);
+
+/**
+ * \brief Calculate ParCor (Partial autoCorrelation, reflection) coefficients
+ * from autocorrelation coefficients using the Schur algorithm (instead of
+ * Levinson Durbin).
+ * \param acorr order+1 autocorrelation coefficients
+ * \param reflCoeff output reflection /ParCor coefficients. The first
+ * coefficient which is always 1.0 is ommitted.
+ * \param order number of acorr / reflCoeff coefficients.
+ * \param pPredictionGain_m prediction gain mantissa
+ * \param pPredictionGain_e prediction gain exponent
+ */
+void CLpc_AutoToParcor(FIXP_DBL acorr[], const int acorr_e,
+                       FIXP_LPC reflCoeff[], const int order,
+                       FIXP_DBL *pPredictionGain_m, INT *pPredictionGain_e);
+
+#endif /* FDK_LPC_H */