#endif
#include "mdct.h"
-#include "kiss_fft.h"
+#include "kfft_double.h"
#include <math.h>
#include "os_support.h"
-#include "_kiss_fft_guts.h"
#include "mathops.h"
#include "stack_alloc.h"
void mdct_init(mdct_lookup *l,int N)
{
int i;
- int N2, N4;
+ int N2;
l->n = N;
- N2 = N/2;
- N4 = N/4;
- l->kfft = kiss_fft_alloc(N4, NULL, NULL);
+ N2 = N>>1;
+ l->kfft = cpx32_fft_alloc(N>>2);
l->trig = (kiss_twiddle_scalar*)celt_alloc(N2*sizeof(kiss_twiddle_scalar));
/* We have enough points that sine isn't necessary */
#if defined(FIXED_POINT)
void mdct_clear(mdct_lookup *l)
{
- kiss_fft_free(l->kfft);
+ cpx32_fft_free(l->kfft);
celt_free(l->trig);
}
-void mdct_forward(const mdct_lookup *l, kiss_fft_scalar *in, kiss_fft_scalar *out)
+/* Only divide by half if float. In fixed-point, it's included in the shift */
+#ifdef FIXED_POINT
+#define FL_HALF(x) (x)
+#else
+#define FL_HALF(x) (.5f*(x))
+#endif
+
+void mdct_forward(const mdct_lookup *l, kiss_fft_scalar *in, kiss_fft_scalar * restrict out, const celt_word16_t *window, int overlap)
{
int i;
int N, N2, N4;
VARDECL(kiss_fft_scalar, f);
SAVE_STACK;
N = l->n;
- N2 = N/2;
- N4 = N/4;
+ N2 = N>>1;
+ N4 = N>>2;
ALLOC(f, N2, kiss_fft_scalar);
/* Consider the input to be compused of four blocks: [a, b, c, d] */
- /* Shuffle, fold, pre-rotate (part 1) */
- for(i=0;i<N/8;i++)
+ /* Window, shuffle, fold */
{
- kiss_fft_scalar re, im;
- /* Real part arranged as -d-cR, Imag part arranged as -b+aR*/
- re = -HALF32(in[N2+N4+2*i] + in[N2+N4-2*i-1]);
- im = -HALF32(in[N4+2*i] - in[N4-2*i-1]);
- out[2*i] = S_MUL(re,l->trig[i]) - S_MUL(im,l->trig[i+N4]);
- out[2*i+1] = S_MUL(im,l->trig[i]) + S_MUL(re,l->trig[i+N4]);
+ /* Temp pointers to make it really clear to the compiler what we're doing */
+ const kiss_fft_scalar * restrict xp1 = in+(overlap>>1);
+ const kiss_fft_scalar * restrict xp2 = in+N2-1+(overlap>>1);
+ kiss_fft_scalar * restrict yp = out;
+ const celt_word16_t * restrict wp1 = window+(overlap>>1);
+ const celt_word16_t * 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++ = -FL_HALF(MULT16_32_Q16(*wp2, xp1[N2]) + MULT16_32_Q16(*wp1,*xp2));
+ *yp++ = -FL_HALF(MULT16_32_Q16(*wp1, *xp1) - MULT16_32_Q16(*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++ = -HALF32(*xp2);
+ *yp++ = -HALF32(*xp1);
+ xp1+=2;
+ xp2-=2;
+ }
+ for(;i<N4;i++)
+ {
+ /* Real part arranged as a-bR, Imag part arranged as -c-dR */
+ *yp++ = FL_HALF(MULT16_32_Q16(*wp1, xp1[-N2]) - MULT16_32_Q16(*wp2, *xp2));
+ *yp++ = -FL_HALF(MULT16_32_Q16(*wp2, *xp1) + MULT16_32_Q16(*wp1, xp2[N2]));
+ xp1+=2;
+ xp2-=2;
+ wp1+=2;
+ wp2-=2;
+ }
}
- for(;i<N4;i++)
+ /* Pre-rotation */
{
- kiss_fft_scalar re, im;
- /* Real part arranged as a-bR, Imag part arranged as -c-dR */
- re = HALF32(in[2*i-N4] - in[N2+N4-2*i-1]);
- im = -HALF32(in[N4+2*i] + in[N+N4-2*i-1]);
- out[2*i] = S_MUL(re,l->trig[i]) - S_MUL(im,l->trig[i+N4]);
- out[2*i+1] = S_MUL(im,l->trig[i]) + S_MUL(re,l->trig[i+N4]);
+ kiss_fft_scalar * restrict yp = out;
+ kiss_fft_scalar *t = &l->trig[0];
+ for(i=0;i<N4;i++)
+ {
+ kiss_fft_scalar re, im;
+ re = yp[0];
+ im = yp[1];
+ *yp++ = S_MUL(re,t[0]) - S_MUL(im,t[N4]);
+ *yp++ = S_MUL(im,t[0]) + S_MUL(re,t[N4]);
+ t++;
+ }
}
/* N/4 complex FFT, which should normally down-scale by 4/N (but doesn't now) */
- kiss_fft(l->kfft, (const kiss_fft_cpx *)out, (kiss_fft_cpx *)f);
+ cpx32_fft(l->kfft, out, f, N4);
/* Post-rotate and apply the scaling if the FFT doesn't to it itself */
- for(i=0;i<N4;i++)
{
- out[2*i] = -S_MUL(f[2*i+1],l->trig[i+N4]) + S_MUL(f[2*i] ,l->trig[i]);
- out[N2-1-2*i] = -S_MUL(f[2*i] ,l->trig[i+N4]) - S_MUL(f[2*i+1],l->trig[i]);
+ /* Temp pointers to make it really clear to the compiler what we're doing */
+ const kiss_fft_scalar * restrict fp = f;
+ kiss_fft_scalar * restrict yp1 = out;
+ kiss_fft_scalar * restrict yp2 = out+N2-1;
+ kiss_fft_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++)
+ {
+ *yp1 = -S_MUL(fp[1],t[N4]) + S_MUL(fp[0],t[0]);
+ *yp2 = -S_MUL(fp[0],t[N4]) - S_MUL(fp[1],t[0]);
+ fp += 2;
+ yp1 += 2;
+ yp2 -= 2;
+ t++;
+ }
}
RESTORE_STACK;
}
-void mdct_backward(const mdct_lookup *l, kiss_fft_scalar *in, kiss_fft_scalar *out)
+void mdct_backward(const mdct_lookup *l, kiss_fft_scalar *in, kiss_fft_scalar * restrict out, const celt_word16_t * restrict window, int overlap)
{
int i;
int N, N2, N4;
VARDECL(kiss_fft_scalar, f);
+ VARDECL(kiss_fft_scalar, f2);
SAVE_STACK;
N = l->n;
- N2 = N/2;
- N4 = N/4;
+ N2 = N>>1;
+ N4 = N>>2;
ALLOC(f, N2, kiss_fft_scalar);
+ ALLOC(f2, N2, kiss_fft_scalar);
/* Pre-rotate */
- for(i=0;i<N4;i++)
{
- out[2*i] = -S_MUL(in[N2-2*i-1], l->trig[i]) - S_MUL(in[2*i],l->trig[i+N4]);
- out[2*i+1] = S_MUL(in[N2-2*i-1], l->trig[i+N4]) - S_MUL(in[2*i],l->trig[i]);
+ /* Temp pointers to make it really clear to the compiler what we're doing */
+ const kiss_fft_scalar * restrict xp1 = in;
+ const kiss_fft_scalar * restrict xp2 = in+N2-1;
+ kiss_fft_scalar * restrict yp = f2;
+ kiss_fft_scalar *t = &l->trig[0];
+ for(i=0;i<N4;i++)
+ {
+ *yp++ = -S_MUL(*xp2, t[0]) - S_MUL(*xp1,t[N4]);
+ *yp++ = S_MUL(*xp2, t[N4]) - S_MUL(*xp1,t[0]);
+ xp1+=2;
+ xp2-=2;
+ t++;
+ }
}
/* Inverse N/4 complex FFT. This one should *not* downscale even in fixed-point */
- kiss_ifft(l->kfft, (const kiss_fft_cpx *)out, (kiss_fft_cpx *)f);
+ cpx32_ifft(l->kfft, f2, f, N4);
/* Post-rotate */
- for(i=0;i<N4;i++)
{
- kiss_fft_scalar re, im;
- re = f[2*i];
- im = f[2*i+1];
- /* We'd scale up by 2 here, but instead it's done when mixing the windows */
- f[2*i] = S_MUL(re,l->trig[i]) + S_MUL(im,l->trig[i+N4]);
- f[2*i+1] = S_MUL(im,l->trig[i]) - S_MUL(re,l->trig[i+N4]);
+ kiss_fft_scalar * restrict fp = f;
+ kiss_fft_scalar *t = &l->trig[0];
+
+ for(i=0;i<N4;i++)
+ {
+ kiss_fft_scalar re, im;
+ re = fp[0];
+ im = fp[1];
+ /* We'd scale up by 2 here, but instead it's done when mixing the windows */
+ *fp++ = S_MUL(re,*t) + S_MUL(im,t[N4]);
+ *fp++ = S_MUL(im,*t) - S_MUL(re,t[N4]);
+ t++;
+ }
}
/* De-shuffle the components for the middle of the window only */
- for(i = 0; i < N4; i++)
{
- out[N4+2*i] =-f[2*i];
- out[N4+2*i+1] = f[N2-2*i-1];
+ const kiss_fft_scalar * restrict fp1 = f;
+ const kiss_fft_scalar * restrict fp2 = f+N2-1;
+ kiss_fft_scalar * restrict yp = f2;
+ for(i = 0; i < N4; i++)
+ {
+ *yp++ =-*fp1*2;
+ *yp++ = *fp2*2;
+ fp1 += 2;
+ fp2 -= 2;
+ }
}
/* Mirror on both sides for TDAC */
- for(i = 0; i < N4; i++)
{
- out[i] =-out[N2-i-1];
- out[N-i-1] = out[N2+i];
+ kiss_fft_scalar * restrict fp1 = f2+N4-1;
+ kiss_fft_scalar * restrict xp1 = out+N2-1;
+ kiss_fft_scalar * restrict yp1 = out+N4-overlap/2;
+ const celt_word16_t * restrict wp1 = window;
+ const celt_word16_t * 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 * restrict fp2 = f2+N4;
+ kiss_fft_scalar * restrict xp2 = out+N2;
+ kiss_fft_scalar * restrict yp2 = out+N-1-(N4-overlap/2);
+ const celt_word16_t * restrict wp1 = window;
+ const celt_word16_t * 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;
}
xiph / opus.git / blobdiff