2 * WMA compatible decoder
3 * Copyright (c) 2002 The FFmpeg Project.
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
28 FFTComplex exptab0[512] IBSS_ATTR;
31 #define BF(pre, pim, qre, qim, pre1, pim1, qre1, qim1) \
33 int32_t ax, ay, bx, by; \
45 int fft_calc_unscaled(FFTContext *s, FFTComplex *z)
50 register FFTComplex *p, *q;
52 int32_t tmp_re, tmp_im;
62 BF(p[0].re, p[0].im, p[1].re, p[1].im,
63 p[0].re, p[0].im, p[1].re, p[1].im);
75 BF(p[0].re, p[0].im, p[2].re, p[2].im,
76 p[0].re, p[0].im, p[2].re, p[2].im);
77 BF(p[1].re, p[1].im, p[3].re, p[3].im,
78 p[1].re, p[1].im, -p[3].im, p[3].re);
87 BF(p[0].re, p[0].im, p[2].re, p[2].im,
88 p[0].re, p[0].im, p[2].re, p[2].im);
89 BF(p[1].re, p[1].im, p[3].re, p[3].im,
90 p[1].re, p[1].im, p[3].im, -p[3].re);
104 for (j = 0; j < nblocks; ++j)
106 BF(p->re, p->im, q->re, q->im,
107 p->re, p->im, q->re, q->im);
111 for(l = nblocks; l < np2; l += nblocks)
113 CMUL(&tmp_re, &tmp_im, exptab0[(l<<tabshift)].re, exptab0[(l<<tabshift)].im, q->re, q->im);
114 //CMUL(&tmp_re, &tmp_im, exptab[l].re, exptab[l].im, q->re, q->im);
115 BF(p->re, p->im, q->re, q->im,
116 p->re, p->im, tmp_re, tmp_im);
124 nblocks = nblocks >> 1;
125 nloops = nloops << 1;
127 while (nblocks != 0);
132 int fft_init_global(void)
142 int32_t ifix = itofix32(i);
143 int32_t nfix = itofix32(n);
144 int32_t res = fixdiv32(ifix,nfix);
146 s1 = fsincos(res<<16, &c1);
149 exptab0[i].im = s1*s2;