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Diffstat (limited to 'fdk-aac/libFDK/src/fft_rad2.cpp')
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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 |