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Making the MDCT produce interleaved data

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This commit is contained in:
Jean-Marc Valin 2011-08-15 10:20:06 -04:00
parent dbeb86fd05
commit a6b4e25628
4 changed files with 19 additions and 22 deletions
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14
libcelt/celt.c
View file

@ -401,32 +401,24 @@ static void compute_mdcts(const CELTMode *mode, int shortBlocks, celt_sig * rest
if (C==1 && !shortBlocks)
{
const int overlap = OVERLAP(mode);
clt_mdct_forward(&mode->mdct, in, out, mode->window, overlap, mode->maxLM-LM);
clt_mdct_forward(&mode->mdct, in, out, mode->window, overlap, mode->maxLM-LM, 1);
} else {
const int overlap = OVERLAP(mode);
int N = mode->shortMdctSize<<LM;
int B = 1;
int b, c;
VARDECL(opus_val32, tmp);
SAVE_STACK;
if (shortBlocks)
{
/*lookup = &mode->mdct[0];*/
N = mode->shortMdctSize;
B = shortBlocks;
}
ALLOC(tmp, N, opus_val32);
c=0; do {
for (b=0;b<B;b++)
{
int j;
clt_mdct_forward(&mode->mdct, in+c*(B*N+overlap)+b*N, tmp, mode->window, overlap, shortBlocks ? mode->maxLM : mode->maxLM-LM);
/* Interleaving the sub-frames */
for (j=0;j<N;j++)
out[(j*B+b)+c*N*B] = tmp[j];
/* Interleaving the sub-frames while doing the MDCTs */
clt_mdct_forward(&mode->mdct, in+c*(B*N+overlap)+b*N, &out[b+c*N*B], mode->window, overlap, shortBlocks ? mode->maxLM : mode->maxLM-LM, B);
}
} while (++c<C);
RESTORE_STACK;
}
}

17
libcelt/mdct.c
View file

@ -99,7 +99,8 @@ void clt_mdct_clear(mdct_lookup *l)
#endif /* CUSTOM_MODES */
void clt_mdct_forward(const mdct_lookup *l, kiss_fft_scalar *in, kiss_fft_scalar * restrict out, const opus_val16 *window, int overlap, int shift)
void clt_mdct_forward(const mdct_lookup *l, kiss_fft_scalar *in, kiss_fft_scalar * restrict out,
const opus_val16 *window, int overlap, int shift, int stride)
{
int i;
int N, N2, N4;
@ -124,7 +125,7 @@ void clt_mdct_forward(const mdct_lookup *l, kiss_fft_scalar *in, kiss_fft_scalar
/* 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;
kiss_fft_scalar * restrict yp = f;
const opus_val16 * restrict wp1 = window+(overlap>>1);
const opus_val16 * restrict wp2 = window+(overlap>>1)-1;
for(i=0;i<(overlap>>2);i++)
@ -160,7 +161,7 @@ void clt_mdct_forward(const mdct_lookup *l, kiss_fft_scalar *in, kiss_fft_scalar
}
/* Pre-rotation */
{
kiss_fft_scalar * restrict yp = out;
kiss_fft_scalar * restrict yp = f;
const kiss_twiddle_scalar *t = &l->trig[0];
for(i=0;i<N4;i++)
{
@ -176,14 +177,14 @@ void clt_mdct_forward(const mdct_lookup *l, kiss_fft_scalar *in, kiss_fft_scalar
}
/* N/4 complex FFT, down-scales by 4/N */
opus_fft(l->kfft[shift], (kiss_fft_cpx *)out, (kiss_fft_cpx *)f);
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 * restrict fp = f;
const kiss_fft_scalar * restrict fp = in;
kiss_fft_scalar * restrict yp1 = out;
kiss_fft_scalar * restrict yp2 = out+N2-1;
kiss_fft_scalar * 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++)
@ -195,8 +196,8 @@ void clt_mdct_forward(const mdct_lookup *l, kiss_fft_scalar *in, kiss_fft_scalar
*yp1 = yr - S_MUL(yi,sine);
*yp2 = yi + S_MUL(yr,sine);;
fp += 2;
yp1 += 2;
yp2 -= 2;
yp1 += 2*stride;
yp2 -= 2*stride;
}
}
RESTORE_STACK;

3
libcelt/mdct.h
View file

@ -56,7 +56,8 @@ int clt_mdct_init(mdct_lookup *l,int N, int maxshift);
void clt_mdct_clear(mdct_lookup *l);
/** Compute a forward MDCT and scale by 4/N */
void clt_mdct_forward(const mdct_lookup *l, kiss_fft_scalar *in, kiss_fft_scalar *out, const opus_val16 *window, int overlap, int shift);
void clt_mdct_forward(const mdct_lookup *l, kiss_fft_scalar *in, kiss_fft_scalar *out,
const opus_val16 *window, int overlap, int shift, int stride);
/** Compute a backward MDCT (no scaling) and performs weighted overlap-add
(scales implicitly by 1/2) */

7
libcelt/tests/mdct-test.c
View file

@ -93,6 +93,7 @@ void test1d(int nfft,int isinverse)
size_t buflen = sizeof(kiss_fft_scalar)*nfft;
kiss_fft_scalar * in = (kiss_fft_scalar*)malloc(buflen);
kiss_fft_scalar * in_copy = (kiss_fft_scalar*)malloc(buflen);
kiss_fft_scalar * out= (kiss_fft_scalar*)malloc(buflen);
opus_val16 * window= (opus_val16*)malloc(sizeof(opus_val16)*nfft/2);
int k;
@ -116,6 +117,8 @@ void test1d(int nfft,int isinverse)
}
}
for (k=0;k<nfft;++k)
in_copy[k] = in[k];
/*for (k=0;k<nfft;++k) printf("%d %d ", in[k].r, in[k].i);printf("\n");*/
if (isinverse)
@ -125,8 +128,8 @@ void test1d(int nfft,int isinverse)
clt_mdct_backward(&cfg,in,out, window, nfft/2, 0, 1);
check_inv(in,out,nfft,isinverse);
} else {
clt_mdct_forward(&cfg,in,out,window, nfft/2, 0);
check(in,out,nfft,isinverse);
clt_mdct_forward(&cfg,in,out,window, nfft/2, 0, 1);
check(in_copy,out,nfft,isinverse);
}
/*for (k=0;k<nfft;++k) printf("%d %d ", out[k].r, out[k].i);printf("\n");*/