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, 324 insertions, 0 deletions

diff --git a/fdk-aac/libFDK/src/fft_rad2.cpp b/fdk-aac/libFDK/src/fft_rad2.cpp
new file mode 100644
index 0000000..27f3aa0
--- /dev/null
+++ b/fdk-aac/libFDK/src/fft_rad2.cpp
@@ -0,0 +1,324 @@
+/* -----------------------------------------------------------------------------
+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):   M. Lohwasser, M. Gayer
+
+   Description:
+
+*******************************************************************************/
+
+#include "fft_rad2.h"
+
+#include "scramble.h"
+
+#define __FFT_RAD2_CPP__
+
+#if defined(__arm__)
+#include "arm/fft_rad2_arm.cpp"
+
+#elif defined(__GNUC__) && defined(__mips__) && defined(__mips_dsp)
+#include "mips/fft_rad2_mips.cpp"
+
+#endif
+
+/*****************************************************************************
+
+    functionname: dit_fft (analysis)
+    description:  dit-tukey-algorithm
+                  scrambles data at entry
+                  i.e. loop is made with scrambled data
+    returns:
+    input:
+    output:
+
+*****************************************************************************/
+
+#ifndef FUNCTION_dit_fft
+
+void dit_fft(FIXP_DBL *x, const INT ldn, const FIXP_STP *trigdata,
+             const INT trigDataSize) {
+  const INT n = 1 << ldn;
+  INT trigstep, i, ldm;
+
+  C_ALLOC_ALIGNED_CHECK(x);
+
+  scramble(x, n);
+  /*
+   * 1+2 stage radix 4
+   */
+
+  for (i = 0; i < n * 2; i += 8) {
+    FIXP_DBL a00, a10, a20, a30;
+    a00 = (x[i + 0] + x[i + 2]) >> 1; /* Re A + Re B */
+    a10 = (x[i + 4] + x[i + 6]) >> 1; /* Re C + Re D */
+    a20 = (x[i + 1] + x[i + 3]) >> 1; /* Im A + Im B */
+    a30 = (x[i + 5] + x[i + 7]) >> 1; /* Im C + Im D */
+
+    x[i + 0] = a00 + a10; /* Re A' = Re A + Re B + Re C + Re D */
+    x[i + 4] = a00 - a10; /* Re C' = Re A + Re B - Re C - Re D */
+    x[i + 1] = a20 + a30; /* Im A' = Im A + Im B + Im C + Im D */
+    x[i + 5] = a20 - a30; /* Im C' = Im A + Im B - Im C - Im D */
+
+    a00 = a00 - x[i + 2]; /* Re A - Re B */
+    a10 = a10 - x[i + 6]; /* Re C - Re D */
+    a20 = a20 - x[i + 3]; /* Im A - Im B */
+    a30 = a30 - x[i + 7]; /* Im C - Im D */
+
+    x[i + 2] = a00 + a30; /* Re B' = Re A - Re B + Im C - Im D */
+    x[i + 6] = a00 - a30; /* Re D' = Re A - Re B - Im C + Im D */
+    x[i + 3] = a20 - a10; /* Im B' = Im A - Im B - Re C + Re D */
+    x[i + 7] = a20 + a10; /* Im D' = Im A - Im B + Re C - Re D */
+  }
+
+  for (ldm = 3; ldm <= ldn; ++ldm) {
+    INT m = (1 << ldm);
+    INT mh = (m >> 1);
+    INT j, r;
+
+    trigstep = ((trigDataSize << 2) >> ldm);
+
+    FDK_ASSERT(trigstep > 0);
+
+    /* Do first iteration with c=1.0 and s=0.0 separately to avoid loosing to
+       much precision. Beware: The impact on the overal FFT precision is rather
+       large. */
+    { /* block 1 */
+
+      j = 0;
+
+      for (r = 0; r < n; r += m) {
+        INT t1 = (r + j) << 1;
+        INT t2 = t1 + (mh << 1);
+        FIXP_DBL vr, vi, ur, ui;
+
+        // cplxMultDiv2(&vi, &vr, x[t2+1], x[t2], (FIXP_SGL)1.0, (FIXP_SGL)0.0);
+        vi = x[t2 + 1] >> 1;
+        vr = x[t2] >> 1;
+
+        ur = x[t1] >> 1;
+        ui = x[t1 + 1] >> 1;
+
+        x[t1] = ur + vr;
+        x[t1 + 1] = ui + vi;
+
+        x[t2] = ur - vr;
+        x[t2 + 1] = ui - vi;
+
+        t1 += mh;
+        t2 = t1 + (mh << 1);
+
+        // cplxMultDiv2(&vr, &vi, x[t2+1], x[t2], (FIXP_SGL)1.0, (FIXP_SGL)0.0);
+        vr = x[t2 + 1] >> 1;
+        vi = x[t2] >> 1;
+
+        ur = x[t1] >> 1;
+        ui = x[t1 + 1] >> 1;
+
+        x[t1] = ur + vr;
+        x[t1 + 1] = ui - vi;
+
+        x[t2] = ur - vr;
+        x[t2 + 1] = ui + vi;
+      }
+
+    } /* end of  block 1 */
+
+    for (j = 1; j < mh / 4; ++j) {
+      FIXP_STP cs;
+
+      cs = trigdata[j * trigstep];
+
+      for (r = 0; r < n; r += m) {
+        INT t1 = (r + j) << 1;
+        INT t2 = t1 + (mh << 1);
+        FIXP_DBL vr, vi, ur, ui;
+
+        cplxMultDiv2(&vi, &vr, x[t2 + 1], x[t2], cs);
+
+        ur = x[t1] >> 1;
+        ui = x[t1 + 1] >> 1;
+
+        x[t1] = ur + vr;
+        x[t1 + 1] = ui + vi;
+
+        x[t2] = ur - vr;
+        x[t2 + 1] = ui - vi;
+
+        t1 += mh;
+        t2 = t1 + (mh << 1);
+
+        cplxMultDiv2(&vr, &vi, x[t2 + 1], x[t2], cs);
+
+        ur = x[t1] >> 1;
+        ui = x[t1 + 1] >> 1;
+
+        x[t1] = ur + vr;
+        x[t1 + 1] = ui - vi;
+
+        x[t2] = ur - vr;
+        x[t2 + 1] = ui + vi;
+
+        /* Same as above but for t1,t2 with j>mh/4 and thus cs swapped */
+        t1 = (r + mh / 2 - j) << 1;
+        t2 = t1 + (mh << 1);
+
+        cplxMultDiv2(&vi, &vr, x[t2], x[t2 + 1], cs);
+
+        ur = x[t1] >> 1;
+        ui = x[t1 + 1] >> 1;
+
+        x[t1] = ur + vr;
+        x[t1 + 1] = ui - vi;
+
+        x[t2] = ur - vr;
+        x[t2 + 1] = ui + vi;
+
+        t1 += mh;
+        t2 = t1 + (mh << 1);
+
+        cplxMultDiv2(&vr, &vi, x[t2], x[t2 + 1], cs);
+
+        ur = x[t1] >> 1;
+        ui = x[t1 + 1] >> 1;
+
+        x[t1] = ur - vr;
+        x[t1 + 1] = ui - vi;
+
+        x[t2] = ur + vr;
+        x[t2 + 1] = ui + vi;
+      }
+    }
+
+    { /* block 2 */
+      j = mh / 4;
+
+      for (r = 0; r < n; r += m) {
+        INT t1 = (r + j) << 1;
+        INT t2 = t1 + (mh << 1);
+        FIXP_DBL vr, vi, ur, ui;
+
+        cplxMultDiv2(&vi, &vr, x[t2 + 1], x[t2], STC(0x5a82799a),
+                     STC(0x5a82799a));
+
+        ur = x[t1] >> 1;
+        ui = x[t1 + 1] >> 1;
+
+        x[t1] = ur + vr;
+        x[t1 + 1] = ui + vi;
+
+        x[t2] = ur - vr;
+        x[t2 + 1] = ui - vi;
+
+        t1 += mh;
+        t2 = t1 + (mh << 1);
+
+        cplxMultDiv2(&vr, &vi, x[t2 + 1], x[t2], STC(0x5a82799a),
+                     STC(0x5a82799a));
+
+        ur = x[t1] >> 1;
+        ui = x[t1 + 1] >> 1;
+
+        x[t1] = ur + vr;
+        x[t1 + 1] = ui - vi;
+
+        x[t2] = ur - vr;
+        x[t2 + 1] = ui + vi;
+      }
+    } /* end of block 2 */
+  }
+}
+
+#endif