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authorSean Bartell <wingedtachikoma@gmail.com>2011-06-25 21:32:25 -0400
committerNils Wallménius <nils@rockbox.org>2012-04-25 22:13:20 +0200
commitf40bfc9267b13b54e6379dfe7539447662879d24 (patch)
tree9b20069d5e62809ff434061ad730096836f916f2 /apps/codecs/libwmavoice/rdft.c
parenta0009907de7a0107d49040d8a180f140e2eff299 (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.c133
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);
-}