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author | The Android Open Source Project <initial-contribution@android.com> | 2012-07-11 10:15:24 -0700 |
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committer | The Android Open Source Project <initial-contribution@android.com> | 2012-07-11 10:15:24 -0700 |
commit | 2228e360595641dd906bf1773307f43d304f5b2e (patch) | |
tree | 57f3d390ebb0782cc0de0fb984c8ea7e45b4f386 /libFDK/src/fft_rad2.cpp | |
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Snapshot 2bda038c163298531d47394bc2c09e1409c5d0db
Change-Id: If584e579464f28b97d50e51fc76ba654a5536c54
Diffstat (limited to 'libFDK/src/fft_rad2.cpp')
-rw-r--r-- | libFDK/src/fft_rad2.cpp | 512 |
1 files changed, 512 insertions, 0 deletions
diff --git a/libFDK/src/fft_rad2.cpp b/libFDK/src/fft_rad2.cpp new file mode 100644 index 0000000..4eaa27e --- /dev/null +++ b/libFDK/src/fft_rad2.cpp @@ -0,0 +1,512 @@ + +/* ----------------------------------------------------------------------------------------------------------- +Software License for The Fraunhofer FDK AAC Codec Library for Android + +© Copyright 1995 - 2012 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 +----------------------------------------------------------------------------------------------------------- */ + +/*************************** Fraunhofer IIS FDK Tools ********************** + + Author(s): M. Lohwasser, M. Gayer + Description: + +******************************************************************************/ + +#include "fft_rad2.h" + +#include "scramble.h" + +#define __FFT_RAD2_CPP__ + +#if defined(__arm__) /* cppp replaced: elif */ +#include "arm/fft_rad2_arm.cpp" + +#elif defined(__GNUC__) && defined(__mips__) && defined(__mips_dsp) /* cppp replaced: elif */ +#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; + + 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. */ + { + 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; + } + } + 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; + } + } + { + 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; + } + } + } +} +#endif + + +/***************************************************************************** + + functionname: dit_ifft (synthesis) + description: dit-tukey-algorithm + scrambles data at entry + i.e. loop is made with scrambled data + returns: + input: + output: + +*****************************************************************************/ + +#if !defined(FUNCTION_dit_ifft) +void dit_ifft(FIXP_DBL *x, const INT ldn, const FIXP_STP *trigdata, const INT trigDataSize) +{ + const INT n=1<<ldn; + INT trigstep,i,ldm; + + scramble(x,n); + + /* + 1+2 stage radix 4 + */ + + for (i=0;i<n*2;i+=8) + { + FIXP_DBL a0, a1, a2, a3, 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 */ + a0 = (x[i + 0] - x[i + 2])>>1; /* Re A - Re B */ + a2 = (x[i + 4] - x[i + 6])>>1; /* Re C - Re D */ + a3 = (x[i + 1] - x[i + 3])>>1; /* Im A - Im B */ + a1 = (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 */ + x[i + 2] = a0 - a1; /* Re B' = Re A - Re B - Im C + Im D */ + x[i + 6] = a0 + a1; /* Re D' = Re A - Re B + Im C - Im D */ + x[i + 3] = a3 + a2; /* Im B' = Im A - Im B + Re C - Re D */ + x[i + 7] = a3 - a2; /* Im D' = Im A - Im B - Re C + Re D */ + } + + for(ldm=3; ldm<=ldn; ++ldm) + { + const INT m=(1<<ldm); + const INT mh=(m>>1); + + INT j,r; + + trigstep=((trigDataSize << 2)>>ldm); + + { + 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(&vr, &vi, x[t2], x[t2+1], FL2FXCONST_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(&vi, &vr, x[t2], x[t2+1], FL2FXCONST_SGL(1.0), FL2FXCONST_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; + } + } + 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(&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; + + t1 += mh; + 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; + + /* 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(&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; + + t1 += mh; + t2 = t1+(mh<<1); + + 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; + } + } + { + j = mh/4; + for(r=0; r<n; r+=m) + { + INT t1 = (r+mh/2-j)<<1; + INT t2 = t1 + (mh<<1); + FIXP_DBL vr,vi,ur,ui; + + cplxMultDiv2(&vr, &vi, x[t2], x[t2+1], 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(&vi, &vr, x[t2], x[t2+1], 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; + } + } + } +} +#endif + |