mirror of
https://github.com/mpv-player/mpv
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73829e43ab
git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@12626 b3059339-0415-0410-9bf9-f77b7e298cf2
521 lines
15 KiB
C
521 lines
15 KiB
C
/*
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** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
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** Copyright (C) 2003-2004 M. Bakker, Ahead Software AG, http://www.nero.com
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**
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** This program is free software; you can redistribute it and/or modify
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** it under the terms of the GNU General Public License as published by
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** the Free Software Foundation; either version 2 of the License, or
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** (at your option) any later version.
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**
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** This program is distributed in the hope that it will be useful,
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** but WITHOUT ANY WARRANTY; without even the implied warranty of
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** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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** GNU General Public License for more details.
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**
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** You should have received a copy of the GNU General Public License
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** along with this program; if not, write to the Free Software
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** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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**
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** Any non-GPL usage of this software or parts of this software is strictly
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** forbidden.
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**
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** Commercial non-GPL licensing of this software is possible.
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** For more info contact Ahead Software through Mpeg4AAClicense@nero.com.
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**
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** Initially modified for use with MPlayer by Arpad Gereöffy on 2003/08/30
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** $Id: mdct.c,v 1.3 2004/06/02 22:59:03 diego Exp $
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** detailed CVS changelog at http://www.mplayerhq.hu/cgi-bin/cvsweb.cgi/main/
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**/
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/*
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* Fast (I)MDCT Implementation using (I)FFT ((Inverse) Fast Fourier Transform)
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* and consists of three steps: pre-(I)FFT complex multiplication, complex
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* (I)FFT, post-(I)FFT complex multiplication,
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*
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* As described in:
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* P. Duhamel, Y. Mahieux, and J.P. Petit, "A Fast Algorithm for the
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* Implementation of Filter Banks Based on 'Time Domain Aliasing
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* Cancellation’," IEEE Proc. on ICASSP‘91, 1991, pp. 2209-2212.
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*
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*
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* As of April 6th 2002 completely rewritten.
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* This (I)MDCT can now be used for any data size n, where n is divisible by 8.
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*
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*/
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#include "common.h"
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#include "structs.h"
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#include <stdlib.h>
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#ifdef _WIN32_WCE
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#define assert(x)
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#else
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#include <assert.h>
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#endif
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#include "cfft.h"
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#include "mdct.h"
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/* const_tab[]:
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0: sqrt(2 / N)
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1: cos(2 * PI / N)
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2: sin(2 * PI / N)
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3: cos(2 * PI * (1/8) / N)
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4: sin(2 * PI * (1/8) / N)
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*/
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#ifdef FIXED_POINT
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real_t const_tab[][5] =
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{
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{ /* 2048 */
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COEF_CONST(1),
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FRAC_CONST(0.99999529380957619),
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FRAC_CONST(0.0030679567629659761),
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FRAC_CONST(0.99999992646571789),
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FRAC_CONST(0.00038349518757139556)
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}, { /* 1920 */
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COEF_CONST(/* sqrt(1024/960) */ 1.0327955589886444),
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FRAC_CONST(0.99999464540169647),
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FRAC_CONST(0.0032724865065266251),
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FRAC_CONST(0.99999991633432805),
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FRAC_CONST(0.00040906153202803459)
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}, { /* 1024 */
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COEF_CONST(1),
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FRAC_CONST(0.99998117528260111),
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FRAC_CONST(0.0061358846491544753),
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FRAC_CONST(0.99999970586288223),
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FRAC_CONST(0.00076699031874270449)
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}, { /* 960 */
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COEF_CONST(/* sqrt(512/480) */ 1.0327955589886444),
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FRAC_CONST(0.99997858166412923),
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FRAC_CONST(0.0065449379673518581),
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FRAC_CONST(0.99999966533732598),
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FRAC_CONST(0.00081812299560725323)
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}, { /* 256 */
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COEF_CONST(1),
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FRAC_CONST(0.99969881869620425),
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FRAC_CONST(0.024541228522912288),
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FRAC_CONST(0.99999529380957619),
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FRAC_CONST(0.0030679567629659761)
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}, { /* 240 */
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COEF_CONST(/* sqrt(256/240) */ 1.0327955589886444),
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FRAC_CONST(0.99965732497555726),
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FRAC_CONST(0.026176948307873149),
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FRAC_CONST(0.99999464540169647),
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FRAC_CONST(0.0032724865065266251)
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}
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#ifdef SSR_DEC
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,{ /* 512 */
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COEF_CONST(1),
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FRAC_CONST(0.9999247018391445),
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FRAC_CONST(0.012271538285719925),
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FRAC_CONST(0.99999882345170188),
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FRAC_CONST(0.0015339801862847655)
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}, { /* 64 */
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COEF_CONST(1),
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FRAC_CONST(0.99518472667219693),
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FRAC_CONST(0.098017140329560604),
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FRAC_CONST(0.9999247018391445),
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FRAC_CONST(0.012271538285719925)
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}
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#endif
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};
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#endif
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#ifdef FIXED_POINT
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static uint8_t map_N_to_idx(uint16_t N)
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{
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/* gives an index into const_tab above */
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/* for normal AAC deocding (eg. no scalable profile) only */
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/* index 0 and 4 will be used */
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switch(N)
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{
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case 2048: return 0;
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case 1920: return 1;
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case 1024: return 2;
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case 960: return 3;
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case 256: return 4;
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case 240: return 5;
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#ifdef SSR_DEC
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case 512: return 6;
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case 64: return 7;
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#endif
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}
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return 0;
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}
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#endif
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mdct_info *faad_mdct_init(uint16_t N)
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{
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uint16_t k;
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#ifdef FIXED_POINT
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uint16_t N_idx;
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real_t cangle, sangle, c, s, cold;
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#endif
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real_t scale;
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mdct_info *mdct = (mdct_info*)faad_malloc(sizeof(mdct_info));
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assert(N % 8 == 0);
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mdct->N = N;
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mdct->sincos = (complex_t*)faad_malloc(N/4*sizeof(complex_t));
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#ifdef FIXED_POINT
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N_idx = map_N_to_idx(N);
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scale = const_tab[N_idx][0];
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cangle = const_tab[N_idx][1];
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sangle = const_tab[N_idx][2];
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c = const_tab[N_idx][3];
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s = const_tab[N_idx][4];
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#else
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scale = (real_t)sqrt(2.0 / (real_t)N);
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#endif
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/* (co)sine table build using recurrence relations */
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/* this can also be done using static table lookup or */
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/* some form of interpolation */
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for (k = 0; k < N/4; k++)
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{
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#ifdef FIXED_POINT
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RE(mdct->sincos[k]) = c; //MUL_C_C(c,scale);
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IM(mdct->sincos[k]) = s; //MUL_C_C(s,scale);
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cold = c;
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c = MUL_F(c,cangle) - MUL_F(s,sangle);
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s = MUL_F(s,cangle) + MUL_F(cold,sangle);
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#else
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/* no recurrence, just sines */
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RE(mdct->sincos[k]) = scale*(real_t)(cos(2.0*M_PI*(k+1./8.) / (real_t)N));
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IM(mdct->sincos[k]) = scale*(real_t)(sin(2.0*M_PI*(k+1./8.) / (real_t)N));
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#endif
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}
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/* initialise fft */
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mdct->cfft = cffti(N/4);
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#ifdef PROFILE
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mdct->cycles = 0;
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mdct->fft_cycles = 0;
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#endif
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return mdct;
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}
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void faad_mdct_end(mdct_info *mdct)
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{
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if (mdct != NULL)
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{
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#ifdef PROFILE
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printf("MDCT[%.4d]: %I64d cycles\n", mdct->N, mdct->cycles);
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printf("CFFT[%.4d]: %I64d cycles\n", mdct->N/4, mdct->fft_cycles);
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#endif
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cfftu(mdct->cfft);
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if (mdct->sincos) faad_free(mdct->sincos);
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faad_free(mdct);
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}
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}
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void faad_imdct(mdct_info *mdct, real_t *X_in, real_t *X_out)
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{
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uint16_t k;
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complex_t x;
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ALIGN complex_t Z1[512];
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complex_t *sincos = mdct->sincos;
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uint16_t N = mdct->N;
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uint16_t N2 = N >> 1;
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uint16_t N4 = N >> 2;
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uint16_t N8 = N >> 3;
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#ifdef PROFILE
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int64_t count1, count2 = faad_get_ts();
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#endif
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/* pre-IFFT complex multiplication */
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for (k = 0; k < N4; k++)
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{
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ComplexMult(&IM(Z1[k]), &RE(Z1[k]),
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X_in[2*k], X_in[N2 - 1 - 2*k], RE(sincos[k]), IM(sincos[k]));
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}
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#ifdef PROFILE
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count1 = faad_get_ts();
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#endif
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/* complex IFFT, any non-scaling FFT can be used here */
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cfftb(mdct->cfft, Z1);
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#ifdef PROFILE
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count1 = faad_get_ts() - count1;
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#endif
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/* post-IFFT complex multiplication */
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for (k = 0; k < N4; k++)
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{
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RE(x) = RE(Z1[k]);
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IM(x) = IM(Z1[k]);
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ComplexMult(&IM(Z1[k]), &RE(Z1[k]),
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IM(x), RE(x), RE(sincos[k]), IM(sincos[k]));
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}
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/* reordering */
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for (k = 0; k < N8; k+=2)
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{
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X_out[ 2*k] = IM(Z1[N8 + k]);
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X_out[ 2 + 2*k] = IM(Z1[N8 + 1 + k]);
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X_out[ 1 + 2*k] = -RE(Z1[N8 - 1 - k]);
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X_out[ 3 + 2*k] = -RE(Z1[N8 - 2 - k]);
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X_out[N4 + 2*k] = RE(Z1[ k]);
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X_out[N4 + + 2 + 2*k] = RE(Z1[ 1 + k]);
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X_out[N4 + 1 + 2*k] = -IM(Z1[N4 - 1 - k]);
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X_out[N4 + 3 + 2*k] = -IM(Z1[N4 - 2 - k]);
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X_out[N2 + 2*k] = RE(Z1[N8 + k]);
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X_out[N2 + + 2 + 2*k] = RE(Z1[N8 + 1 + k]);
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X_out[N2 + 1 + 2*k] = -IM(Z1[N8 - 1 - k]);
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X_out[N2 + 3 + 2*k] = -IM(Z1[N8 - 2 - k]);
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X_out[N2 + N4 + 2*k] = -IM(Z1[ k]);
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X_out[N2 + N4 + 2 + 2*k] = -IM(Z1[ 1 + k]);
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X_out[N2 + N4 + 1 + 2*k] = RE(Z1[N4 - 1 - k]);
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X_out[N2 + N4 + 3 + 2*k] = RE(Z1[N4 - 2 - k]);
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}
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#ifdef PROFILE
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count2 = faad_get_ts() - count2;
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mdct->fft_cycles += count1;
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mdct->cycles += (count2 - count1);
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#endif
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}
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#ifdef USE_SSE
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void faad_imdct_sse(mdct_info *mdct, real_t *X_in, real_t *X_out)
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{
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uint16_t k;
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ALIGN complex_t Z1[512];
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complex_t *sincos = mdct->sincos;
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uint16_t N = mdct->N;
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uint16_t N2 = N >> 1;
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uint16_t N4 = N >> 2;
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uint16_t N8 = N >> 3;
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#ifdef PROFILE
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int64_t count1, count2 = faad_get_ts();
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#endif
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/* pre-IFFT complex multiplication */
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for (k = 0; k < N4; k+=4)
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{
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__m128 m12, m13, m14, m0, m1, m2, m3, m4, m5, m6, m7, m8, m9, m10, m11;
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__m128 n12, n13, n14, n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11;
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n12 = _mm_load_ps(&X_in[N2 - 2*k - 8]);
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m12 = _mm_load_ps(&X_in[N2 - 2*k - 4]);
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m13 = _mm_load_ps(&X_in[2*k]);
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n13 = _mm_load_ps(&X_in[2*k + 4]);
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m1 = _mm_load_ps(&RE(sincos[k]));
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n1 = _mm_load_ps(&RE(sincos[k+2]));
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m0 = _mm_shuffle_ps(m12, m13, _MM_SHUFFLE(2,0,1,3));
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m2 = _mm_shuffle_ps(m1, m1, _MM_SHUFFLE(2,3,0,1));
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m14 = _mm_shuffle_ps(m0, m0, _MM_SHUFFLE(3,1,2,0));
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n0 = _mm_shuffle_ps(n12, n13, _MM_SHUFFLE(2,0,1,3));
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n2 = _mm_shuffle_ps(n1, n1, _MM_SHUFFLE(2,3,0,1));
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n14 = _mm_shuffle_ps(n0, n0, _MM_SHUFFLE(3,1,2,0));
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m3 = _mm_mul_ps(m14, m1);
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n3 = _mm_mul_ps(n14, n1);
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m4 = _mm_mul_ps(m14, m2);
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n4 = _mm_mul_ps(n14, n2);
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m5 = _mm_shuffle_ps(m3, m4, _MM_SHUFFLE(2,0,2,0));
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n5 = _mm_shuffle_ps(n3, n4, _MM_SHUFFLE(2,0,2,0));
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m6 = _mm_shuffle_ps(m3, m4, _MM_SHUFFLE(3,1,3,1));
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n6 = _mm_shuffle_ps(n3, n4, _MM_SHUFFLE(3,1,3,1));
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m7 = _mm_add_ps(m5, m6);
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n7 = _mm_add_ps(n5, n6);
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m8 = _mm_sub_ps(m5, m6);
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n8 = _mm_sub_ps(n5, n6);
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m9 = _mm_shuffle_ps(m7, m7, _MM_SHUFFLE(3,2,3,2));
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n9 = _mm_shuffle_ps(n7, n7, _MM_SHUFFLE(3,2,3,2));
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m10 = _mm_shuffle_ps(m8, m8, _MM_SHUFFLE(1,0,1,0));
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n10 = _mm_shuffle_ps(n8, n8, _MM_SHUFFLE(1,0,1,0));
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m11 = _mm_unpacklo_ps(m10, m9);
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n11 = _mm_unpacklo_ps(n10, n9);
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_mm_store_ps(&RE(Z1[k]), m11);
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_mm_store_ps(&RE(Z1[k+2]), n11);
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}
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#ifdef PROFILE
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count1 = faad_get_ts();
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#endif
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/* complex IFFT, any non-scaling FFT can be used here */
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cfftb_sse(mdct->cfft, Z1);
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#ifdef PROFILE
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count1 = faad_get_ts() - count1;
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#endif
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/* post-IFFT complex multiplication */
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for (k = 0; k < N4; k+=4)
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{
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__m128 m0, m1, m2, m3, m4, m5, m6, m7, m8, m9, m10, m11;
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__m128 n0, n1, n2, n3, n4, n5, n6, n7, n8, n9, n10, n11;
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m0 = _mm_load_ps(&RE(Z1[k]));
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n0 = _mm_load_ps(&RE(Z1[k+2]));
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m1 = _mm_load_ps(&RE(sincos[k]));
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n1 = _mm_load_ps(&RE(sincos[k+2]));
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m2 = _mm_shuffle_ps(m1, m1, _MM_SHUFFLE(2,3,0,1));
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n2 = _mm_shuffle_ps(n1, n1, _MM_SHUFFLE(2,3,0,1));
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m3 = _mm_mul_ps(m0, m1);
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n3 = _mm_mul_ps(n0, n1);
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m4 = _mm_mul_ps(m0, m2);
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n4 = _mm_mul_ps(n0, n2);
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m5 = _mm_shuffle_ps(m3, m4, _MM_SHUFFLE(2,0,2,0));
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n5 = _mm_shuffle_ps(n3, n4, _MM_SHUFFLE(2,0,2,0));
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m6 = _mm_shuffle_ps(m3, m4, _MM_SHUFFLE(3,1,3,1));
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n6 = _mm_shuffle_ps(n3, n4, _MM_SHUFFLE(3,1,3,1));
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m7 = _mm_add_ps(m5, m6);
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n7 = _mm_add_ps(n5, n6);
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m8 = _mm_sub_ps(m5, m6);
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n8 = _mm_sub_ps(n5, n6);
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m9 = _mm_shuffle_ps(m7, m7, _MM_SHUFFLE(3,2,3,2));
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n9 = _mm_shuffle_ps(n7, n7, _MM_SHUFFLE(3,2,3,2));
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m10 = _mm_shuffle_ps(m8, m8, _MM_SHUFFLE(1,0,1,0));
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n10 = _mm_shuffle_ps(n8, n8, _MM_SHUFFLE(1,0,1,0));
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m11 = _mm_unpacklo_ps(m10, m9);
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n11 = _mm_unpacklo_ps(n10, n9);
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_mm_store_ps(&RE(Z1[k]), m11);
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_mm_store_ps(&RE(Z1[k+2]), n11);
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}
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/* reordering */
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for (k = 0; k < N8; k+=2)
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{
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__m128 m0, m1, m2, m3, m4, m5, m6, m7, m8, m9, m10, m11, m13;
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__m128 n4, n5, n6, n7, n8, n9;
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__m128 neg1 = _mm_set_ps(-1.0, 1.0, -1.0, 1.0);
|
||
__m128 neg2 = _mm_set_ps(-1.0, -1.0, -1.0, -1.0);
|
||
|
||
m0 = _mm_load_ps(&RE(Z1[k]));
|
||
m1 = _mm_load_ps(&RE(Z1[N8 - 2 - k]));
|
||
m2 = _mm_load_ps(&RE(Z1[N8 + k]));
|
||
m3 = _mm_load_ps(&RE(Z1[N4 - 2 - k]));
|
||
|
||
m10 = _mm_mul_ps(m0, neg1);
|
||
m11 = _mm_mul_ps(m1, neg2);
|
||
m13 = _mm_mul_ps(m3, neg1);
|
||
|
||
m5 = _mm_shuffle_ps(m2, m2, _MM_SHUFFLE(3,1,2,0));
|
||
n4 = _mm_shuffle_ps(m10, m10, _MM_SHUFFLE(3,1,2,0));
|
||
m4 = _mm_shuffle_ps(m11, m11, _MM_SHUFFLE(3,1,2,0));
|
||
n5 = _mm_shuffle_ps(m13, m13, _MM_SHUFFLE(3,1,2,0));
|
||
|
||
m6 = _mm_shuffle_ps(m4, m5, _MM_SHUFFLE(3,2,1,0));
|
||
n6 = _mm_shuffle_ps(n4, n5, _MM_SHUFFLE(3,2,1,0));
|
||
m7 = _mm_shuffle_ps(m5, m4, _MM_SHUFFLE(3,2,1,0));
|
||
n7 = _mm_shuffle_ps(n5, n4, _MM_SHUFFLE(3,2,1,0));
|
||
|
||
m8 = _mm_shuffle_ps(m6, m6, _MM_SHUFFLE(0,3,1,2));
|
||
n8 = _mm_shuffle_ps(n6, n6, _MM_SHUFFLE(2,1,3,0));
|
||
m9 = _mm_shuffle_ps(m7, m7, _MM_SHUFFLE(2,1,3,0));
|
||
n9 = _mm_shuffle_ps(n7, n7, _MM_SHUFFLE(0,3,1,2));
|
||
|
||
_mm_store_ps(&X_out[2*k], m8);
|
||
_mm_store_ps(&X_out[N4 + 2*k], n8);
|
||
_mm_store_ps(&X_out[N2 + 2*k], m9);
|
||
_mm_store_ps(&X_out[N2 + N4 + 2*k], n9);
|
||
}
|
||
|
||
#ifdef PROFILE
|
||
count2 = faad_get_ts() - count2;
|
||
mdct->fft_cycles += count1;
|
||
mdct->cycles += (count2 - count1);
|
||
#endif
|
||
}
|
||
#endif
|
||
|
||
#ifdef LTP_DEC
|
||
void faad_mdct(mdct_info *mdct, real_t *X_in, real_t *X_out)
|
||
{
|
||
uint16_t k;
|
||
|
||
complex_t x;
|
||
ALIGN complex_t Z1[512];
|
||
complex_t *sincos = mdct->sincos;
|
||
|
||
uint16_t N = mdct->N;
|
||
uint16_t N2 = N >> 1;
|
||
uint16_t N4 = N >> 2;
|
||
uint16_t N8 = N >> 3;
|
||
|
||
#ifndef FIXED_POINT
|
||
real_t scale = REAL_CONST(N);
|
||
#else
|
||
real_t scale = REAL_CONST(4.0/N);
|
||
#endif
|
||
|
||
/* pre-FFT complex multiplication */
|
||
for (k = 0; k < N8; k++)
|
||
{
|
||
uint16_t n = k << 1;
|
||
RE(x) = X_in[N - N4 - 1 - n] + X_in[N - N4 + n];
|
||
IM(x) = X_in[ N4 + n] - X_in[ N4 - 1 - n];
|
||
|
||
ComplexMult(&RE(Z1[k]), &IM(Z1[k]),
|
||
RE(x), IM(x), RE(sincos[k]), IM(sincos[k]));
|
||
|
||
RE(Z1[k]) = MUL_R(RE(Z1[k]), scale);
|
||
IM(Z1[k]) = MUL_R(IM(Z1[k]), scale);
|
||
|
||
RE(x) = X_in[N2 - 1 - n] - X_in[ n];
|
||
IM(x) = X_in[N2 + n] + X_in[N - 1 - n];
|
||
|
||
ComplexMult(&RE(Z1[k + N8]), &IM(Z1[k + N8]),
|
||
RE(x), IM(x), RE(sincos[k + N8]), IM(sincos[k + N8]));
|
||
|
||
RE(Z1[k + N8]) = MUL_R(RE(Z1[k + N8]), scale);
|
||
IM(Z1[k + N8]) = MUL_R(IM(Z1[k + N8]), scale);
|
||
}
|
||
|
||
/* complex FFT, any non-scaling FFT can be used here */
|
||
cfftf(mdct->cfft, Z1);
|
||
|
||
/* post-FFT complex multiplication */
|
||
for (k = 0; k < N4; k++)
|
||
{
|
||
uint16_t n = k << 1;
|
||
ComplexMult(&RE(x), &IM(x),
|
||
RE(Z1[k]), IM(Z1[k]), RE(sincos[k]), IM(sincos[k]));
|
||
|
||
X_out[ n] = -RE(x);
|
||
X_out[N2 - 1 - n] = IM(x);
|
||
X_out[N2 + n] = -IM(x);
|
||
X_out[N - 1 - n] = RE(x);
|
||
}
|
||
}
|
||
#endif
|