[xiph-cvs] cvs commit: speex/libspeex mdf.c speex_echo.h
Jean-Marc Valin
jm at xiph.org
Mon Aug 18 20:59:27 PDT 2003
jm 03/08/18 23:59:27
Modified: libspeex mdf.c speex_echo.h
Log:
added normalization. Should be roughly equivalent to NLMS.
Revision Changes Path
1.2 +69 -10 speex/libspeex/mdf.c
Index: mdf.c
===================================================================
RCS file: /usr/local/cvsroot/speex/libspeex/mdf.c,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- mdf.c 18 Aug 2003 21:52:14 -0000 1.1
+++ mdf.c 19 Aug 2003 03:59:27 -0000 1.2
@@ -45,6 +45,7 @@
st->window_size = 2*frame_size;
N = st->window_size;
M = st->M = (filter_length+N-1)/frame_size;
+ st->cancel_count=0;
drft_init(&st->fft_lookup, N);
@@ -56,7 +57,8 @@
st->E = (float*)speex_alloc(N*sizeof(float));
st->W = (float*)speex_alloc(M*N*sizeof(float));
st->PHI = (float*)speex_alloc(N*sizeof(float));
-
+ st->power = (float*)speex_alloc((frame_size+1)*sizeof(float));
+ st->power_1 = (float*)speex_alloc((frame_size+1)*sizeof(float));
return st;
}
@@ -68,13 +70,14 @@
/** Performs echo cancellation a frame */
void speex_echo_cancel(SpeexEchoState *st, float *ref, float *echo, float *out, float *Yout)
{
- int i,j;
+ int i,j,m;
int N,M;
float scale;
N = st->window_size;
M = st->M;
scale = 1.0/N;
+ st->cancel_count++;
for (i=0;i<st->frame_size;i++)
{
@@ -91,6 +94,7 @@
drft_forward(&st->fft_lookup, &st->X[(M-1)*N]);
+ /* Compute filter response Y */
for (i=1;i<N-1;i+=2)
{
st->Y[i] = st->Y[i+1] = 0;
@@ -101,6 +105,11 @@
}
}
st->Y[0] = st->Y[N-1] = 0;
+ for (j=0;j<M;j++)
+ {
+ st->Y[0] += st->X[j*N]*st->W[j*N];
+ st->Y[N-1] += st->X[(j+1)*N-1]*st->W[(j+1)*N-1];
+ }
if (Yout)
for (i=0;i<N;i++)
@@ -109,15 +118,12 @@
for (i=0;i<N;i++)
st->y[i] = st->Y[i];
-#if 0
- for (i=0;i<N;i++)
- st->y[i] = st->X[(M-1)*N+i];
-#endif
-
+ /* Filter response in time domain */
drft_backward(&st->fft_lookup, st->y);
for (i=0;i<N;i++)
st->y[i] *= scale;
+ /* Compute error signal (echo canceller output) */
for (i=0;i<st->frame_size;i++)
{
out[i] = ref[i] - st->y[i+st->frame_size];
@@ -127,6 +133,52 @@
drft_forward(&st->fft_lookup, st->E);
+
+ /* Compute input power in each band */
+ {
+ float s;
+ float tmp, tmp2;
+
+ if (st->cancel_count<M)
+ s = 1.0/st->cancel_count;
+ else
+ s = 1.0/M;
+
+ for (i=1,j=1;i<N-1;i+=2,j++)
+ {
+ tmp=0;
+ for (m=0;m<M;m++)
+ {
+ tmp += st->X[m*N+i]*st->X[m*N+i] + st->X[m*N+i+1]*st->X[m*N+i+1];
+ }
+ tmp *= s;
+ if (st->cancel_count<M)
+ st->power[j] = tmp;
+ else
+ st->power[j] = .8*st->power[j] + .2*tmp;
+ }
+ tmp=tmp2=0;
+ for (m=0;m<M;m++)
+ {
+ tmp += st->X[m*N]*st->X[m*N];
+ tmp2 += st->X[(m+1)*N-1]*st->X[(m+1)*N-1];
+ }
+ tmp *= s;
+ tmp2 *= s;
+ if (st->cancel_count<M)
+ {
+ st->power[0] = tmp;
+ st->power[st->frame_size] = tmp2;
+ } else {
+ st->power[0] = .8*st->power[0] + .2*tmp;
+ st->power[st->frame_size] = .8*st->power[st->frame_size] + .2*tmp2;
+ }
+
+ for (i=0;i<=st->frame_size;i++)
+ st->power_1[i] = 1.0/(1e-10+st->power[i]);
+ }
+
+ /* Update filter weights */
for (j=0;j<M;j++)
{
for (i=1;i<N-1;i+=2)
@@ -134,12 +186,19 @@
st->PHI[i] = st->X[j*N+i]*st->E[i] + st->X[j*N+i+1]*st->E[i+1];
st->PHI[i+1] = -st->X[j*N+i+1]*st->E[i] + st->X[j*N+i]*st->E[i+1];
}
- st->PHI[0] = st->PHI[N-1] = 0;
+ st->PHI[0] = st->X[j*N]*st->E[0];
+ st->PHI[N-1] = st->X[(j+1)*N-1]*st->E[N-1];
/* Optionally perform some transform (normalization?) on PHI */
- for (i=0;i<N;i++)
- st->W[j*N+i] += .002*st->PHI[i];
+ for (i=1,m=1;i<N-1;i+=2,m++)
+ st->W[j*N+i] += .1*st->PHI[i]*st->power_1[m];
+ st->W[j*N] += .1*st->PHI[0]*st->power_1[0];
+ st->W[(j+1)*N-1] += .1*st->PHI[N-1]*st->power_1[st->frame_size];
+ /*
+ for (i=0,j=0;i<=N;i++,j++)
+ st->W[j*N+i] += .001*st->PHI[i];
+ */
}
}
<p><p>1.2 +4 -1 speex/libspeex/speex_echo.h
Index: speex_echo.h
===================================================================
RCS file: /usr/local/cvsroot/speex/libspeex/speex_echo.h,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- speex_echo.h 18 Aug 2003 21:52:14 -0000 1.1
+++ speex_echo.h 19 Aug 2003 03:59:27 -0000 1.2
@@ -36,6 +36,7 @@
int frame_size; /**< Number of samples processed each time */
int window_size;
int M;
+ int cancel_count;
float *x;
float *X;
@@ -44,7 +45,9 @@
float *E;
float *PHI;
float *W;
-
+ float *power;
+ float *power_1;
+
drft_lookup fft_lookup;
<p><p>--- >8 ----
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