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, 174 insertions, 0 deletions

diff --git a/fdk-aac/libFDK/include/arm/scramble_arm.h b/fdk-aac/libFDK/include/arm/scramble_arm.h
new file mode 100644
index 0000000..a7cfe65
--- /dev/null
+++ b/fdk-aac/libFDK/include/arm/scramble_arm.h
@@ -0,0 +1,174 @@
+/* -----------------------------------------------------------------------------
+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):
+
+   Description: bitreversal of input data
+
+*******************************************************************************/
+
+#if !defined(SCRAMBLE_ARM_H)
+#define SCRAMBLE_ARM_H
+
+#if defined(FUNCTION_scramble)
+#if defined(__GNUC__)
+
+#define FUNCTION_scramble
+
+#if defined(__ARM_ARCH_5TE__)
+#define USE_LDRD_STRD /* LDRD requires 8 byte data alignment. */
+#endif
+
+inline void scramble(FIXP_DBL x[], INT n) {
+  FDK_ASSERT(!(((INT)x) & (ALIGNMENT_DEFAULT - 1)));
+  asm("mov     r2, #1;\n"     /* r2(m) = 1;           */
+      "sub     r3, %1, #1;\n" /* r3 = n-1;            */
+      "mov     r4, #0;\n"     /* r4(j) = 0;           */
+
+      "scramble_m_loop%=:\n" /* {                    */
+      "mov     r5, %1;\n"    /*  r5(k) = 1;          */
+
+      "scramble_k_loop%=:\n"         /*  {                   */
+      "mov     r5, r5, lsr #1;\n"    /*   k >>= 1;           */
+      "eor     r4, r4, r5;\n"        /*   j ^=k;             */
+      "ands    r10, r4, r5;\n"       /*   r10 = r4 & r5;      */
+      "beq     scramble_k_loop%=;\n" /*  } while (r10 == 0);  */
+
+      "cmp     r4, r2;\n" /*   if (r4 < r2) break;        */
+      "bcc     scramble_m_loop_end%=;\n"
+
+#ifdef USE_LDRD_STRD
+      "mov     r5, r2, lsl #3;\n" /* m(r5) = r2*4*2               */
+      "ldrd    r10, [%0, r5];\n"  /* r10 = x[r5], x7 = x[r5+1]     */
+      "mov     r6, r4, lsl #3;\n" /* j(r6) = r4*4*2              */
+      "ldrd    r8, [%0, r6];\n"   /* r8 = x[r6], r9 = x[r6+1];  */
+      "strd    r10, [%0, r6];\n"  /* x[r6,r6+1] = r10,r11;        */
+      "strd    r8, [%0, r5];\n"   /* x[r5,r5+1] = r8,r9;          */
+#else
+      "mov      r5, r2, lsl #3;\n" /* m(r5) = r2*4*2               */
+      "ldr      r10, [%0, r5];\n"
+      "mov      r6, r4, lsl #3;\n" /* j(r6) = r4*4*2              */
+      "ldr      r11, [%0, r6];\n"
+
+      "str      r10, [%0, r6];\n"
+      "str      r11, [%0, r5];\n"
+
+      "add      r5, r5, #4;"
+      "ldr      r10, [%0, r5];\n"
+      "add      r6, r6, #4;"
+      "ldr      r11, [%0, r6];\n"
+      "str      r10, [%0, r6];\n"
+      "str      r11, [%0, r5];\n"
+#endif
+      "scramble_m_loop_end%=:\n"
+      "add     r2, r2, #1;\n" /* r2++;                        */
+      "cmp     r2, r3;\n"
+      "bcc     scramble_m_loop%=;\n" /* } while (r2(m) < r3(n-1));   */
+      :
+      : "r"(x), "r"(n)
+#ifdef USE_LDRD_STRD
+      : "r2", "r3", "r4", "r5", "r10", "r11", "r8", "r9", "r6");
+#else
+      : "r2", "r3", "r4", "r5", "r10", "r11", "r6");
+#endif
+}
+#else
+/* Force C implementation if no assembler version available. */
+#undef FUNCTION_scramble
+#endif /* Toolchain selection. */
+
+#endif /* defined(FUNCTION_scramble) */
+#endif /* !defined(SCRAMBLE_ARM_H) */