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-rw-r--r--flib/src/cc~.c199
-rw-r--r--flib/src/flib.c4
-rw-r--r--flib/src/flib.h2
3 files changed, 202 insertions, 3 deletions
diff --git a/flib/src/cc~.c b/flib/src/cc~.c
new file mode 100644
index 0000000..2d06d9b
--- /dev/null
+++ b/flib/src/cc~.c
@@ -0,0 +1,199 @@
+/* flib - PD library for feature extraction
+ Copyright (C) 2005 Jamie Bullock
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License
+ as published by the Free Software Foundation; either version 2
+ of the License, or (at your option) any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+
+/*Calculate the cross correlation of two signal vectors*/
+
+/*The time domain implementation is based on code by Phil Bourke
+ * the frequency domain version is based on code by Charles Henry
+ *
+ * Specify a time delay as an argument for the time domain implemenation, for example an argument of 32 will give the correlation coefficients for delays from -32 to 32 samples between the two input vectors
+ *
+ * Specify an argument of 'f' for the frequency domain implementation*/
+
+
+#include "flib.h"
+#define SQ(a) (a * a)
+
+static t_class *cross_class;
+
+typedef struct _cross {
+ t_object x_obj;
+ t_float f;
+ t_int delay;
+ t_int is_freq_domain;
+} t_cross;
+
+static t_int *cross_perform_time_domain(t_int *w)
+{
+ t_sample *x = (t_sample *)(w[1]);
+ t_sample *y = (t_sample *)(w[2]);
+ t_sample *out = (t_sample *)(w[3]);
+ t_int N = (t_int)(w[4]),
+ i, j, delay;
+ t_int maxdelay = (t_int)(w[5]);
+ t_float mx, my, sx, sy, sxy, denom, r;
+
+ if(maxdelay > N * .5){
+ maxdelay = N * .5;
+ post("cross~: invalid maxdelay, must be <= blocksize/2");
+ }
+
+/* Calculate the mean of the two series x[], y[] */
+ mx = 0;
+ my = 0;
+ for (i=0;i<N;i++) {
+ mx += x[i];
+ my += y[i];
+ }
+ mx /= N;
+ my /= N;
+
+ /* Calculate the denominator */
+ sx = 0;
+ sy = 0;
+ for (i=0;i<N;i++) {
+ sx += (x[i] - mx) * (x[i] - mx);
+ sy += (y[i] - my) * (y[i] - my);
+ }
+ denom = sqrt(sx*sy);
+
+ /* Calculate the correlation series */
+ for (delay=-maxdelay;delay<maxdelay;delay++) {
+ sxy = 0;
+ for (i=0;i<N;i++) {
+ j = i + delay;
+
+ /* circular correlation */
+ while (j < 0)
+ j += N;
+ j %= N;
+ sxy += (x[i] - mx) * (y[j] - my);
+
+ }
+ r = sxy / denom;
+ *out++ = r;
+ /* r is the correlation coefficient at "delay" */
+
+ }
+
+ return (w+6);
+
+}
+
+
+t_int *cross_perform_freq_domain(t_int *w)
+{
+ t_cross *x = (t_cross *)(w[1]);
+
+ t_sample *sig1 = (t_sample *)(w[2]);
+ t_sample *sig2 = (t_sample *)(w[3]);
+ t_sample *out = (t_sample *)(w[4]);
+ long int size = (long int) w[5];
+ long int k = size/2;
+ float *expsig1 = NULL;
+ float *revsig2 = NULL;
+ float temp, temp2;
+ long int i=0;
+ int well_defined=1;
+ int qtr, thrqtr;
+
+// The two signals are created, nonzero on 0 to N/4 and 3N/4 to N
+// This will be revised
+
+ expsig1=(float *) alloca(size*sizeof(float));
+ revsig2=(float *) alloca(size*sizeof(float));
+ qtr = size/4;
+ thrqtr = 3*size/4;
+ for (i=0; i < qtr ; i++)
+ {
+ expsig1[i]=sig1[i];
+ revsig2[i]=0;
+ }
+ for (i=qtr; i < thrqtr ; i++)
+ {
+ expsig1[i]=sig1[i];
+ revsig2[i]=sig2[size-i];
+ }
+ for (i=thrqtr; i < size ; i++)
+ {
+ expsig1[i]=sig1[i];
+ revsig2[i]=0;
+ }
+
+ mayer_realfft(size, expsig1);
+ mayer_realfft(size, revsig2);
+ expsig1[0]*=revsig2[0];
+ expsig1[k]*=revsig2[k];
+ for(i=1; i < k; i++)
+ {
+ temp=expsig1[i];
+ temp2=expsig1[size-i];
+ expsig1[i]=temp*revsig2[i]-temp2*revsig2[size-i];
+ expsig1[size-i]=temp*revsig2[size-i]+temp2*revsig2[i];
+ }
+
+ mayer_realifft(size, expsig1);
+ for(i=0; i < size; i++)
+ {
+ out[i]=expsig1[i];
+ }
+
+ return(w+6);
+
+}
+
+static void cross_dsp(t_cross *x, t_signal **sp)
+{
+ if(!x->is_freq_domain)
+ dsp_add(cross_perform_time_domain, 5,
+ sp[0]->s_vec, sp[1]->s_vec, sp[2]->s_vec, sp[0]->s_n, x->delay);
+ else
+ dsp_add(cross_perform_freq_domain, 5, x,
+ sp[0]->s_vec, sp[1]->s_vec, sp[2]->s_vec, sp[0]->s_n);
+}
+
+static void *cross_new(t_symbol *s, t_int argc, t_atom *argv)
+{
+ t_cross *x = (t_cross *)pd_new(cross_class);
+
+ if(atom_getsymbol(argv) == gensym("f")){
+ x->is_freq_domain = 1;
+ post("flib: cross: Frequency domain selected");
+ }
+ else {
+ x->delay = atom_getfloat(argv);
+ post("flib: cross: Time domain selected");
+ }
+ inlet_new(&x->x_obj, &x->x_obj.ob_pd, &s_signal, &s_signal);
+ outlet_new(&x->x_obj, &s_signal);
+ return (void *)x;
+}
+
+
+void cross_tilde_setup(void) {
+ cross_class = class_new(gensym("cross~"),
+ (t_newmethod)cross_new,
+ 0, sizeof(t_cross),
+ CLASS_DEFAULT, A_GIMME, 0);
+
+ class_addmethod(cross_class,
+ (t_method)cross_dsp, gensym("dsp"), 0);
+ CLASS_MAINSIGNALIN(cross_class, t_cross,f);
+ class_sethelpsymbol(cross_class, gensym("help-flib"));
+}
diff --git a/flib/src/flib.c b/flib/src/flib.c
index 8db11f4..1cdcfb0 100644
--- a/flib/src/flib.c
+++ b/flib/src/flib.c
@@ -36,7 +36,7 @@ void flib_setup(void)
{
int i;
- char *ext[] = {"sc~\t\tSpectral Centroid", "ss~\t\tSpectral Smoothness", "irreg~\t\tSpectral Irregularity (methods 1 and 2)", "mspec~\t\tMagnitude Spectrum", "peak~\t\tAmplitude and Frequency of Spectral Peaks", "pspec~\t\tPhase Spectrum", "sfm~\t\tSpectral Flatness Measure", "trist~\t\tTristimulus (x,y,z)", "++~\t\tSum of the samples in each block", "bmax~\t\tThe maximum value and location(s) each block", "melf~\t\tGenerate a mel spaced filter for fft", "clean~\t\tRemoves NaN, inf and -inf from a signal vector", "wdv~\t\tCalculate a wavelet dispersion vector (requires creb)", "hca~\t\tHarmonic component analysis", "cross~\t\tCross correlation"};
+ char *ext[] = {"sc~\t\tSpectral Centroid", "ss~\t\tSpectral Smoothness", "irreg~\t\tSpectral Irregularity (methods 1 and 2)", "mspec~\t\tMagnitude Spectrum", "peak~\t\tAmplitude and Frequency of Spectral Peaks", "pspec~\t\tPhase Spectrum", "sfm~\t\tSpectral Flatness Measure", "trist~\t\tTristimulus (x,y,z)", "++~\t\tSum of the samples in each block", "bmax~\t\tThe maximum value and location(s) each block", "melf~\t\tGenerate a mel spaced filter for fft", "clean~\t\tRemoves NaN, inf and -inf from a signal vector", "wdv~\t\tCalculate a wavelet dispersion vector (requires creb)", "hca~\t\tHarmonic component analysis", "cc~\t\tCross correlation"};
sc_tilde_setup();
ss_tilde_setup();
pp_tilde_setup();
@@ -51,7 +51,7 @@ void flib_setup(void)
clean_tilde_setup();
wdv_tilde_setup();
hca_tilde_setup();
- cross_tilde_setup();
+ cc_tilde_setup();
post("\n\tflib "VERSION" Feature Extraction Library\n\tby Jamie Bullock\n");
diff --git a/flib/src/flib.h b/flib/src/flib.h
index 868f683..c43f63b 100644
--- a/flib/src/flib.h
+++ b/flib/src/flib.h
@@ -37,5 +37,5 @@ void melf_tilde_setup(void);
void clean_tilde_setup(void);
void wdv_tilde_setup(void);
void hca_tilde_setup(void);
-void cross_tilde_setup(void);
+void cc_tilde_setup(void);