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, 263 insertions, 0 deletions

diff --git a/fdk-aac/libFDK/include/fft.h b/fdk-aac/libFDK/include/fft.h
new file mode 100644
index 0000000..d394046
--- /dev/null
+++ b/fdk-aac/libFDK/include/fft.h
@@ -0,0 +1,263 @@
+/* -----------------------------------------------------------------------------
+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):   Josef Hoepfl, DSP Solutions
+
+   Description: Fix point FFT
+
+*******************************************************************************/
+
+#ifndef FFT_H
+#define FFT_H
+
+#include "common_fix.h"
+
+/**
+ * \brief Perform an inplace complex valued FFT of length 2^n
+ *
+ * \param length Length of the FFT to be calculated.
+ * \param pInput Input/Output data buffer. The input data must have at least 1
+ * bit scale headroom. The values are interleaved, real/imag pairs.
+ * \param scalefactor Pointer to an INT, which contains the current scale of the
+ * input data, which is updated according to the FFT scale.
+ */
+void fft(int length, FIXP_DBL *pInput, INT *scalefactor);
+
+/**
+ * \brief Perform an inplace complex valued IFFT of length 2^n
+ *
+ * \param length Length of the FFT to be calculated.
+ * \param pInput Input/Output data buffer. The input data must have at least 1
+ * bit scale headroom. The values are interleaved, real/imag pairs.
+ * \param scalefactor Pointer to an INT, which contains the current scale of the
+ * input data, which is updated according to the IFFT scale.
+ */
+void ifft(int length, FIXP_DBL *pInput, INT *scalefactor);
+
+/*
+ * Frequently used and fixed short length FFTs.
+ */
+
+#ifndef FUNCTION_fft_4
+/**
+ * \brief Perform an inplace complex valued FFT of length 4
+ *
+ * \param pInput Input/Output data buffer. The input data must have at least 1
+ * bit scale headroom. The values are interleaved, real/imag pairs.
+ */
+LNK_SECTION_CODE_L1
+static FDK_FORCEINLINE void fft_4(FIXP_DBL *x) {
+  FIXP_DBL a00, a10, a20, a30, tmp0, tmp1;
+
+  a00 = (x[0] + x[4]) >> 1; /* Re A + Re B */
+  a10 = (x[2] + x[6]) >> 1; /* Re C + Re D */
+  a20 = (x[1] + x[5]) >> 1; /* Im A + Im B */
+  a30 = (x[3] + x[7]) >> 1; /* Im C + Im D */
+
+  x[0] = a00 + a10; /* Re A' = Re A + Re B + Re C + Re D */
+  x[1] = a20 + a30; /* Im A' = Im A + Im B + Im C + Im D */
+
+  tmp0 = a00 - x[4]; /* Re A - Re B */
+  tmp1 = a20 - x[5]; /* Im A - Im B */
+
+  x[4] = a00 - a10; /* Re C' = Re A + Re B - Re C - Re D */
+  x[5] = a20 - a30; /* Im C' = Im A + Im B - Im C - Im D */
+
+  a10 = a10 - x[6]; /* Re C - Re D */
+  a30 = a30 - x[7]; /* Im C - Im D */
+
+  x[2] = tmp0 + a30; /* Re B' = Re A - Re B + Im C - Im D */
+  x[6] = tmp0 - a30; /* Re D' = Re A - Re B - Im C + Im D */
+  x[3] = tmp1 - a10; /* Im B' = Im A - Im B - Re C + Re D */
+  x[7] = tmp1 + a10; /* Im D' = Im A - Im B + Re C - Re D */
+}
+#endif /* FUNCTION_fft_4 */
+
+#ifndef FUNCTION_fft_8
+LNK_SECTION_CODE_L1
+static FDK_FORCEINLINE void fft_8(FIXP_DBL *x) {
+  FIXP_SPK w_PiFOURTH = {{FIXP_SGL(0x5A82), FIXP_SGL(0x5A82)}};
+
+  FIXP_DBL a00, a10, a20, a30;
+  FIXP_DBL y[16];
+
+  a00 = (x[0] + x[8]) >> 1;
+  a10 = x[4] + x[12];
+  a20 = (x[1] + x[9]) >> 1;
+  a30 = x[5] + x[13];
+
+  y[0] = a00 + (a10 >> 1);
+  y[4] = a00 - (a10 >> 1);
+  y[1] = a20 + (a30 >> 1);
+  y[5] = a20 - (a30 >> 1);
+
+  a00 = a00 - x[8];
+  a10 = (a10 >> 1) - x[12];
+  a20 = a20 - x[9];
+  a30 = (a30 >> 1) - x[13];
+
+  y[2] = a00 + a30;
+  y[6] = a00 - a30;
+  y[3] = a20 - a10;
+  y[7] = a20 + a10;
+
+  a00 = (x[2] + x[10]) >> 1;
+  a10 = x[6] + x[14];
+  a20 = (x[3] + x[11]) >> 1;
+  a30 = x[7] + x[15];
+
+  y[8] = a00 + (a10 >> 1);
+  y[12] = a00 - (a10 >> 1);
+  y[9] = a20 + (a30 >> 1);
+  y[13] = a20 - (a30 >> 1);
+
+  a00 = a00 - x[10];
+  a10 = (a10 >> 1) - x[14];
+  a20 = a20 - x[11];
+  a30 = (a30 >> 1) - x[15];
+
+  y[10] = a00 + a30;
+  y[14] = a00 - a30;
+  y[11] = a20 - a10;
+  y[15] = a20 + a10;
+
+  FIXP_DBL vr, vi, ur, ui;
+
+  ur = y[0] >> 1;
+  ui = y[1] >> 1;
+  vr = y[8];
+  vi = y[9];
+  x[0] = ur + (vr >> 1);
+  x[1] = ui + (vi >> 1);
+  x[8] = ur - (vr >> 1);
+  x[9] = ui - (vi >> 1);
+
+  ur = y[4] >> 1;
+  ui = y[5] >> 1;
+  vi = y[12];
+  vr = y[13];
+  x[4] = ur + (vr >> 1);
+  x[5] = ui - (vi >> 1);
+  x[12] = ur - (vr >> 1);
+  x[13] = ui + (vi >> 1);
+
+  ur = y[10];
+  ui = y[11];
+
+  cplxMultDiv2(&vi, &vr, ui, ur, w_PiFOURTH);
+
+  ur = y[2];
+  ui = y[3];
+  x[2] = (ur >> 1) + vr;
+  x[3] = (ui >> 1) + vi;
+  x[10] = (ur >> 1) - vr;
+  x[11] = (ui >> 1) - vi;
+
+  ur = y[14];
+  ui = y[15];
+
+  cplxMultDiv2(&vr, &vi, ui, ur, w_PiFOURTH);
+
+  ur = y[6];
+  ui = y[7];
+  x[6] = (ur >> 1) + vr;
+  x[7] = (ui >> 1) - vi;
+  x[14] = (ur >> 1) - vr;
+  x[15] = (ui >> 1) + vi;
+}
+#endif /* FUNCTION_fft_8 */
+
+#endif