yading@10: /*
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: #define CONFIG_FFT_FLOAT 0
yading@10: #include "mdct.c"
yading@10: 
yading@10: /* same as ff_mdct_calcw_c with double-width unscaled output */
yading@10: void ff_mdct_calcw_c(FFTContext *s, FFTDouble *out, const FFTSample *input)
yading@10: {
yading@10:     int i, j, n, n8, n4, n2, n3;
yading@10:     FFTDouble re, im;
yading@10:     const uint16_t *revtab = s->revtab;
yading@10:     const FFTSample *tcos = s->tcos;
yading@10:     const FFTSample *tsin = s->tsin;
yading@10:     FFTComplex *x = s->tmp_buf;
yading@10:     FFTDComplex *o = (FFTDComplex *)out;
yading@10: 
yading@10:     n = 1 << s->mdct_bits;
yading@10:     n2 = n >> 1;
yading@10:     n4 = n >> 2;
yading@10:     n8 = n >> 3;
yading@10:     n3 = 3 * n4;
yading@10: 
yading@10:     /* pre rotation */
yading@10:     for(i=0;i<n8;i++) {
yading@10:         re = RSCALE(-input[2*i+n3] - input[n3-1-2*i]);
yading@10:         im = RSCALE(-input[n4+2*i] + input[n4-1-2*i]);
yading@10:         j = revtab[i];
yading@10:         CMUL(x[j].re, x[j].im, re, im, -tcos[i], tsin[i]);
yading@10: 
yading@10:         re = RSCALE( input[2*i]    - input[n2-1-2*i]);
yading@10:         im = RSCALE(-input[n2+2*i] - input[ n-1-2*i]);
yading@10:         j = revtab[n8 + i];
yading@10:         CMUL(x[j].re, x[j].im, re, im, -tcos[n8 + i], tsin[n8 + i]);
yading@10:     }
yading@10: 
yading@10:     s->fft_calc(s, x);
yading@10: 
yading@10:     /* post rotation */
yading@10:     for(i=0;i<n8;i++) {
yading@10:         FFTDouble r0, i0, r1, i1;
yading@10:         CMULL(i1, r0, x[n8-i-1].re, x[n8-i-1].im, -tsin[n8-i-1], -tcos[n8-i-1]);
yading@10:         CMULL(i0, r1, x[n8+i  ].re, x[n8+i  ].im, -tsin[n8+i  ], -tcos[n8+i  ]);
yading@10:         o[n8-i-1].re = r0;
yading@10:         o[n8-i-1].im = i0;
yading@10:         o[n8+i  ].re = r1;
yading@10:         o[n8+i  ].im = i1;
yading@10:     }
yading@10: }