| Index: opus/celt/mdct.c
|
| ===================================================================
|
| --- opus/celt/mdct.c (revision 0)
|
| +++ opus/celt/mdct.c (revision 0)
|
| @@ -0,0 +1,332 @@
|
| +/* Copyright (c) 2007-2008 CSIRO
|
| + Copyright (c) 2007-2008 Xiph.Org Foundation
|
| + Written by Jean-Marc Valin */
|
| +/*
|
| + Redistribution and use in source and binary forms, with or without
|
| + modification, are permitted provided that the following conditions
|
| + are met:
|
| +
|
| + - Redistributions of source code must retain the above copyright
|
| + notice, this list of conditions and the following disclaimer.
|
| +
|
| + - Redistributions in binary form must reproduce the above copyright
|
| + notice, this list of conditions and the following disclaimer in the
|
| + documentation and/or other materials provided with the distribution.
|
| +
|
| + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
| + ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
| + LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
| + A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
|
| + OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
|
| + EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
|
| + PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
|
| + PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
|
| + LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
|
| + NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
|
| + SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
| +*/
|
| +
|
| +/* This is a simple MDCT implementation that uses a N/4 complex FFT
|
| + to do most of the work. It should be relatively straightforward to
|
| + plug in pretty much and FFT here.
|
| +
|
| + This replaces the Vorbis FFT (and uses the exact same API), which
|
| + was a bit too messy and that was ending up duplicating code
|
| + (might as well use the same FFT everywhere).
|
| +
|
| + The algorithm is similar to (and inspired from) Fabrice Bellard's
|
| + MDCT implementation in FFMPEG, but has differences in signs, ordering
|
| + and scaling in many places.
|
| +*/
|
| +
|
| +#ifndef SKIP_CONFIG_H
|
| +#ifdef HAVE_CONFIG_H
|
| +#include "config.h"
|
| +#endif
|
| +#endif
|
| +
|
| +#include "mdct.h"
|
| +#include "kiss_fft.h"
|
| +#include "_kiss_fft_guts.h"
|
| +#include <math.h>
|
| +#include "os_support.h"
|
| +#include "mathops.h"
|
| +#include "stack_alloc.h"
|
| +
|
| +#ifdef CUSTOM_MODES
|
| +
|
| +int clt_mdct_init(mdct_lookup *l,int N, int maxshift)
|
| +{
|
| + int i;
|
| + int N4;
|
| + kiss_twiddle_scalar *trig;
|
| +#if defined(FIXED_POINT)
|
| + int N2=N>>1;
|
| +#endif
|
| + l->n = N;
|
| + N4 = N>>2;
|
| + l->maxshift = maxshift;
|
| + for (i=0;i<=maxshift;i++)
|
| + {
|
| + if (i==0)
|
| + l->kfft[i] = opus_fft_alloc(N>>2>>i, 0, 0);
|
| + else
|
| + l->kfft[i] = opus_fft_alloc_twiddles(N>>2>>i, 0, 0, l->kfft[0]);
|
| +#ifndef ENABLE_TI_DSPLIB55
|
| + if (l->kfft[i]==NULL)
|
| + return 0;
|
| +#endif
|
| + }
|
| + l->trig = trig = (kiss_twiddle_scalar*)opus_alloc((N4+1)*sizeof(kiss_twiddle_scalar));
|
| + if (l->trig==NULL)
|
| + return 0;
|
| + /* We have enough points that sine isn't necessary */
|
| +#if defined(FIXED_POINT)
|
| + for (i=0;i<=N4;i++)
|
| + trig[i] = TRIG_UPSCALE*celt_cos_norm(DIV32(ADD32(SHL32(EXTEND32(i),17),N2),N));
|
| +#else
|
| + for (i=0;i<=N4;i++)
|
| + trig[i] = (kiss_twiddle_scalar)cos(2*PI*i/N);
|
| +#endif
|
| + return 1;
|
| +}
|
| +
|
| +void clt_mdct_clear(mdct_lookup *l)
|
| +{
|
| + int i;
|
| + for (i=0;i<=l->maxshift;i++)
|
| + opus_fft_free(l->kfft[i]);
|
| + opus_free((kiss_twiddle_scalar*)l->trig);
|
| +}
|
| +
|
| +#endif /* CUSTOM_MODES */
|
| +
|
| +/* Forward MDCT trashes the input array */
|
| +void clt_mdct_forward(const mdct_lookup *l, kiss_fft_scalar *in, kiss_fft_scalar * OPUS_RESTRICT out,
|
| + const opus_val16 *window, int overlap, int shift, int stride)
|
| +{
|
| + int i;
|
| + int N, N2, N4;
|
| + kiss_twiddle_scalar sine;
|
| + VARDECL(kiss_fft_scalar, f);
|
| + SAVE_STACK;
|
| + N = l->n;
|
| + N >>= shift;
|
| + N2 = N>>1;
|
| + N4 = N>>2;
|
| + ALLOC(f, N2, kiss_fft_scalar);
|
| + /* sin(x) ~= x here */
|
| +#ifdef FIXED_POINT
|
| + sine = TRIG_UPSCALE*(QCONST16(0.7853981f, 15)+N2)/N;
|
| +#else
|
| + sine = (kiss_twiddle_scalar)2*PI*(.125f)/N;
|
| +#endif
|
| +
|
| + /* Consider the input to be composed of four blocks: [a, b, c, d] */
|
| + /* Window, shuffle, fold */
|
| + {
|
| + /* Temp pointers to make it really clear to the compiler what we're doing */
|
| + const kiss_fft_scalar * OPUS_RESTRICT xp1 = in+(overlap>>1);
|
| + const kiss_fft_scalar * OPUS_RESTRICT xp2 = in+N2-1+(overlap>>1);
|
| + kiss_fft_scalar * OPUS_RESTRICT yp = f;
|
| + const opus_val16 * OPUS_RESTRICT wp1 = window+(overlap>>1);
|
| + const opus_val16 * OPUS_RESTRICT wp2 = window+(overlap>>1)-1;
|
| + for(i=0;i<(overlap>>2);i++)
|
| + {
|
| + /* Real part arranged as -d-cR, Imag part arranged as -b+aR*/
|
| + *yp++ = MULT16_32_Q15(*wp2, xp1[N2]) + MULT16_32_Q15(*wp1,*xp2);
|
| + *yp++ = MULT16_32_Q15(*wp1, *xp1) - MULT16_32_Q15(*wp2, xp2[-N2]);
|
| + xp1+=2;
|
| + xp2-=2;
|
| + wp1+=2;
|
| + wp2-=2;
|
| + }
|
| + wp1 = window;
|
| + wp2 = window+overlap-1;
|
| + for(;i<N4-(overlap>>2);i++)
|
| + {
|
| + /* Real part arranged as a-bR, Imag part arranged as -c-dR */
|
| + *yp++ = *xp2;
|
| + *yp++ = *xp1;
|
| + xp1+=2;
|
| + xp2-=2;
|
| + }
|
| + for(;i<N4;i++)
|
| + {
|
| + /* Real part arranged as a-bR, Imag part arranged as -c-dR */
|
| + *yp++ = -MULT16_32_Q15(*wp1, xp1[-N2]) + MULT16_32_Q15(*wp2, *xp2);
|
| + *yp++ = MULT16_32_Q15(*wp2, *xp1) + MULT16_32_Q15(*wp1, xp2[N2]);
|
| + xp1+=2;
|
| + xp2-=2;
|
| + wp1+=2;
|
| + wp2-=2;
|
| + }
|
| + }
|
| + /* Pre-rotation */
|
| + {
|
| + kiss_fft_scalar * OPUS_RESTRICT yp = f;
|
| + const kiss_twiddle_scalar *t = &l->trig[0];
|
| + for(i=0;i<N4;i++)
|
| + {
|
| + kiss_fft_scalar re, im, yr, yi;
|
| + re = yp[0];
|
| + im = yp[1];
|
| + yr = -S_MUL(re,t[i<<shift]) - S_MUL(im,t[(N4-i)<<shift]);
|
| + yi = -S_MUL(im,t[i<<shift]) + S_MUL(re,t[(N4-i)<<shift]);
|
| + /* works because the cos is nearly one */
|
| + *yp++ = yr + S_MUL(yi,sine);
|
| + *yp++ = yi - S_MUL(yr,sine);
|
| + }
|
| + }
|
| +
|
| + /* N/4 complex FFT, down-scales by 4/N */
|
| + opus_fft(l->kfft[shift], (kiss_fft_cpx *)f, (kiss_fft_cpx *)in);
|
| +
|
| + /* Post-rotate */
|
| + {
|
| + /* Temp pointers to make it really clear to the compiler what we're doing */
|
| + const kiss_fft_scalar * OPUS_RESTRICT fp = in;
|
| + kiss_fft_scalar * OPUS_RESTRICT yp1 = out;
|
| + kiss_fft_scalar * OPUS_RESTRICT yp2 = out+stride*(N2-1);
|
| + const kiss_twiddle_scalar *t = &l->trig[0];
|
| + /* Temp pointers to make it really clear to the compiler what we're doing */
|
| + for(i=0;i<N4;i++)
|
| + {
|
| + kiss_fft_scalar yr, yi;
|
| + yr = S_MUL(fp[1],t[(N4-i)<<shift]) + S_MUL(fp[0],t[i<<shift]);
|
| + yi = S_MUL(fp[0],t[(N4-i)<<shift]) - S_MUL(fp[1],t[i<<shift]);
|
| + /* works because the cos is nearly one */
|
| + *yp1 = yr - S_MUL(yi,sine);
|
| + *yp2 = yi + S_MUL(yr,sine);;
|
| + fp += 2;
|
| + yp1 += 2*stride;
|
| + yp2 -= 2*stride;
|
| + }
|
| + }
|
| + RESTORE_STACK;
|
| +}
|
| +
|
| +void clt_mdct_backward(const mdct_lookup *l, kiss_fft_scalar *in, kiss_fft_scalar * OPUS_RESTRICT out,
|
| + const opus_val16 * OPUS_RESTRICT window, int overlap, int shift, int stride)
|
| +{
|
| + int i;
|
| + int N, N2, N4;
|
| + kiss_twiddle_scalar sine;
|
| + VARDECL(kiss_fft_scalar, f);
|
| + VARDECL(kiss_fft_scalar, f2);
|
| + SAVE_STACK;
|
| + N = l->n;
|
| + N >>= shift;
|
| + N2 = N>>1;
|
| + N4 = N>>2;
|
| + ALLOC(f, N2, kiss_fft_scalar);
|
| + ALLOC(f2, N2, kiss_fft_scalar);
|
| + /* sin(x) ~= x here */
|
| +#ifdef FIXED_POINT
|
| + sine = TRIG_UPSCALE*(QCONST16(0.7853981f, 15)+N2)/N;
|
| +#else
|
| + sine = (kiss_twiddle_scalar)2*PI*(.125f)/N;
|
| +#endif
|
| +
|
| + /* Pre-rotate */
|
| + {
|
| + /* Temp pointers to make it really clear to the compiler what we're doing */
|
| + const kiss_fft_scalar * OPUS_RESTRICT xp1 = in;
|
| + const kiss_fft_scalar * OPUS_RESTRICT xp2 = in+stride*(N2-1);
|
| + kiss_fft_scalar * OPUS_RESTRICT yp = f2;
|
| + const kiss_twiddle_scalar *t = &l->trig[0];
|
| + for(i=0;i<N4;i++)
|
| + {
|
| + kiss_fft_scalar yr, yi;
|
| + yr = -S_MUL(*xp2, t[i<<shift]) + S_MUL(*xp1,t[(N4-i)<<shift]);
|
| + yi = -S_MUL(*xp2, t[(N4-i)<<shift]) - S_MUL(*xp1,t[i<<shift]);
|
| + /* works because the cos is nearly one */
|
| + *yp++ = yr - S_MUL(yi,sine);
|
| + *yp++ = yi + S_MUL(yr,sine);
|
| + xp1+=2*stride;
|
| + xp2-=2*stride;
|
| + }
|
| + }
|
| +
|
| + /* Inverse N/4 complex FFT. This one should *not* downscale even in fixed-point */
|
| + opus_ifft(l->kfft[shift], (kiss_fft_cpx *)f2, (kiss_fft_cpx *)f);
|
| +
|
| + /* Post-rotate */
|
| + {
|
| + kiss_fft_scalar * OPUS_RESTRICT fp = f;
|
| + const kiss_twiddle_scalar *t = &l->trig[0];
|
| +
|
| + for(i=0;i<N4;i++)
|
| + {
|
| + kiss_fft_scalar re, im, yr, yi;
|
| + re = fp[0];
|
| + im = fp[1];
|
| + /* We'd scale up by 2 here, but instead it's done when mixing the windows */
|
| + yr = S_MUL(re,t[i<<shift]) - S_MUL(im,t[(N4-i)<<shift]);
|
| + yi = S_MUL(im,t[i<<shift]) + S_MUL(re,t[(N4-i)<<shift]);
|
| + /* works because the cos is nearly one */
|
| + *fp++ = yr - S_MUL(yi,sine);
|
| + *fp++ = yi + S_MUL(yr,sine);
|
| + }
|
| + }
|
| + /* De-shuffle the components for the middle of the window only */
|
| + {
|
| + const kiss_fft_scalar * OPUS_RESTRICT fp1 = f;
|
| + const kiss_fft_scalar * OPUS_RESTRICT fp2 = f+N2-1;
|
| + kiss_fft_scalar * OPUS_RESTRICT yp = f2;
|
| + for(i = 0; i < N4; i++)
|
| + {
|
| + *yp++ =-*fp1;
|
| + *yp++ = *fp2;
|
| + fp1 += 2;
|
| + fp2 -= 2;
|
| + }
|
| + }
|
| + out -= (N2-overlap)>>1;
|
| + /* Mirror on both sides for TDAC */
|
| + {
|
| + kiss_fft_scalar * OPUS_RESTRICT fp1 = f2+N4-1;
|
| + kiss_fft_scalar * OPUS_RESTRICT xp1 = out+N2-1;
|
| + kiss_fft_scalar * OPUS_RESTRICT yp1 = out+N4-overlap/2;
|
| + const opus_val16 * OPUS_RESTRICT wp1 = window;
|
| + const opus_val16 * OPUS_RESTRICT wp2 = window+overlap-1;
|
| + for(i = 0; i< N4-overlap/2; i++)
|
| + {
|
| + *xp1 = *fp1;
|
| + xp1--;
|
| + fp1--;
|
| + }
|
| + for(; i < N4; i++)
|
| + {
|
| + kiss_fft_scalar x1;
|
| + x1 = *fp1--;
|
| + *yp1++ +=-MULT16_32_Q15(*wp1, x1);
|
| + *xp1-- += MULT16_32_Q15(*wp2, x1);
|
| + wp1++;
|
| + wp2--;
|
| + }
|
| + }
|
| + {
|
| + kiss_fft_scalar * OPUS_RESTRICT fp2 = f2+N4;
|
| + kiss_fft_scalar * OPUS_RESTRICT xp2 = out+N2;
|
| + kiss_fft_scalar * OPUS_RESTRICT yp2 = out+N-1-(N4-overlap/2);
|
| + const opus_val16 * OPUS_RESTRICT wp1 = window;
|
| + const opus_val16 * OPUS_RESTRICT wp2 = window+overlap-1;
|
| + for(i = 0; i< N4-overlap/2; i++)
|
| + {
|
| + *xp2 = *fp2;
|
| + xp2++;
|
| + fp2++;
|
| + }
|
| + for(; i < N4; i++)
|
| + {
|
| + kiss_fft_scalar x2;
|
| + x2 = *fp2++;
|
| + *yp2-- = MULT16_32_Q15(*wp1, x2);
|
| + *xp2++ = MULT16_32_Q15(*wp2, x2);
|
| + wp1++;
|
| + wp2--;
|
| + }
|
| + }
|
| + RESTORE_STACK;
|
| +}
|
|
|
| Property changes on: opus/celt/mdct.c
|
| ___________________________________________________________________
|
| Added: svn:eol-style
|
| + LF
|
|
|
|
|