diff options
author | Sean Bartell <wingedtachikoma@gmail.com> | 2011-06-25 21:32:25 -0400 |
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committer | Nils Wallménius <nils@rockbox.org> | 2012-04-25 22:13:20 +0200 |
commit | f40bfc9267b13b54e6379dfe7539447662879d24 (patch) | |
tree | 9b20069d5e62809ff434061ad730096836f916f2 /apps/codecs/libwmavoice/rdft.c | |
parent | a0009907de7a0107d49040d8a180f140e2eff299 (diff) |
Add codecs to librbcodec.
Change-Id: Id7f4717d51ed02d67cb9f9cb3c0ada4a81843f97
Reviewed-on: http://gerrit.rockbox.org/137
Reviewed-by: Nils Wallménius <nils@rockbox.org>
Tested-by: Nils Wallménius <nils@rockbox.org>
Diffstat (limited to 'apps/codecs/libwmavoice/rdft.c')
-rw-r--r-- | apps/codecs/libwmavoice/rdft.c | 133 |
1 files changed, 0 insertions, 133 deletions
diff --git a/apps/codecs/libwmavoice/rdft.c b/apps/codecs/libwmavoice/rdft.c deleted file mode 100644 index bc44f5aef2..0000000000 --- a/apps/codecs/libwmavoice/rdft.c +++ /dev/null @@ -1,133 +0,0 @@ -/* - * (I)RDFT transforms - * Copyright (c) 2009 Alex Converse <alex dot converse at gmail dot com> - * - * This file is part of FFmpeg. - * - * FFmpeg is free software; you can redistribute it and/or - * modify it under the terms of the GNU Lesser General Public - * License as published by the Free Software Foundation; either - * version 2.1 of the License, or (at your option) any later version. - * - * FFmpeg is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * Lesser General Public License for more details. - * - * You should have received a copy of the GNU Lesser General Public - * License along with FFmpeg; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA - */ -#include <stdlib.h> -#include <math.h> -#include "libavutil/mathematics.h" -#include "fft.h" - -/** - * @file - * (Inverse) Real Discrete Fourier Transforms. - */ - -/* sin(2*pi*x/n) for 0<=x<n/4, followed by n/2<=x<3n/4 */ -#if !CONFIG_HARDCODED_TABLES -SINTABLE(16); -SINTABLE(32); -SINTABLE(64); -SINTABLE(128); -SINTABLE(256); -SINTABLE(512); -SINTABLE(1024); -SINTABLE(2048); -SINTABLE(4096); -SINTABLE(8192); -SINTABLE(16384); -SINTABLE(32768); -SINTABLE(65536); -#endif -SINTABLE_CONST FFTSample * const ff_sin_tabs[] = { - NULL, NULL, NULL, NULL, - ff_sin_16, ff_sin_32, ff_sin_64, ff_sin_128, ff_sin_256, ff_sin_512, ff_sin_1024, - ff_sin_2048, ff_sin_4096, ff_sin_8192, ff_sin_16384, ff_sin_32768, ff_sin_65536, -}; - -/** Map one real FFT into two parallel real even and odd FFTs. Then interleave - * the two real FFTs into one complex FFT. Unmangle the results. - * ref: http://www.engineeringproductivitytools.com/stuff/T0001/PT10.HTM - */ -static void ff_rdft_calc_c(RDFTContext* s, FFTSample* data) -{ - int i, i1, i2; - FFTComplex ev, od; - const int n = 1 << s->nbits; - const float k1 = 0.5; - const float k2 = 0.5 - s->inverse; - const FFTSample *tcos = s->tcos; - const FFTSample *tsin = s->tsin; - - if (!s->inverse) { - ff_fft_permute(&s->fft, (FFTComplex*)data); - ff_fft_calc(&s->fft, (FFTComplex*)data); - } - /* i=0 is a special case because of packing, the DC term is real, so we - are going to throw the N/2 term (also real) in with it. */ - ev.re = data[0]; - data[0] = ev.re+data[1]; - data[1] = ev.re-data[1]; - for (i = 1; i < (n>>2); i++) { - i1 = 2*i; - i2 = n-i1; - /* Separate even and odd FFTs */ - ev.re = k1*(data[i1 ]+data[i2 ]); - od.im = -k2*(data[i1 ]-data[i2 ]); - ev.im = k1*(data[i1+1]-data[i2+1]); - od.re = k2*(data[i1+1]+data[i2+1]); - /* Apply twiddle factors to the odd FFT and add to the even FFT */ - data[i1 ] = ev.re + od.re*tcos[i] - od.im*tsin[i]; - data[i1+1] = ev.im + od.im*tcos[i] + od.re*tsin[i]; - data[i2 ] = ev.re - od.re*tcos[i] + od.im*tsin[i]; - data[i2+1] = -ev.im + od.im*tcos[i] + od.re*tsin[i]; - } - data[2*i+1]=s->sign_convention*data[2*i+1]; - if (s->inverse) { - data[0] *= k1; - data[1] *= k1; - ff_fft_permute(&s->fft, (FFTComplex*)data); - ff_fft_calc(&s->fft, (FFTComplex*)data); - } -} - -av_cold int ff_rdft_init(RDFTContext *s, int nbits, enum RDFTransformType trans) -{ - int n = 1 << nbits; - int i; - const double theta = (trans == DFT_R2C || trans == DFT_C2R ? -1 : 1)*2*M_PI/n; - - s->nbits = nbits; - s->inverse = trans == IDFT_C2R || trans == DFT_C2R; - s->sign_convention = trans == IDFT_R2C || trans == DFT_C2R ? 1 : -1; - - if (nbits < 4 || nbits > 16) - return -1; - - if (ff_fft_init(&s->fft, nbits-1, trans == IDFT_C2R || trans == IDFT_R2C) < 0) - return -1; - - ff_init_ff_cos_tabs(nbits); - s->tcos = ff_cos_tabs[nbits]; - s->tsin = ff_sin_tabs[nbits]+(trans == DFT_R2C || trans == DFT_C2R)*(n>>2); -#if !CONFIG_HARDCODED_TABLES - for (i = 0; i < (n>>2); i++) { - s->tsin[i] = sin(i*theta); - } -#endif - s->rdft_calc = ff_rdft_calc_c; - - //if (ARCH_ARM) ff_rdft_init_arm(s); - - return 0; -} - -av_cold void ff_rdft_end(RDFTContext *s) -{ - ff_fft_end(&s->fft); -} |