From efa45f81b5dcb9609b1e2365a51b7a25a1ba2ce0 Mon Sep 17 00:00:00 2001 From: Georg Holzmann Date: Tue, 12 Jul 2005 14:09:53 +0000 Subject: initial commit of adaptive svn path=/trunk/externals/grh/; revision=3317 --- adaptive/src/nlms~.c | 324 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 324 insertions(+) create mode 100755 adaptive/src/nlms~.c (limited to 'adaptive/src/nlms~.c') diff --git a/adaptive/src/nlms~.c b/adaptive/src/nlms~.c new file mode 100755 index 0000000..5ebc4f5 --- /dev/null +++ b/adaptive/src/nlms~.c @@ -0,0 +1,324 @@ +/****************************************************** + * + * Adaptive Systems for PD + * + * copyleft (c) Gerda Strobl, Georg Holzmann + * 2005 + * + * for complaints, suggestions: grh@mur.at + * + ****************************************************** + * + * license: GNU General Public License v.2 + * + ******************************************************/ + +#include "adaptive.h" + + +/* ------------------------ nlms~ ------------------------- */ + +static t_class *nlms_tilde_class; + +typedef struct _nlms +{ + t_object x_obj; + t_float f; + t_sample *buf; + t_sample *tmp; + t_int bufsize; + int adapt; // enable/disable adaptation + + t_int N; //number of coefficients of the adaptive system + t_float *c; // coefficients of the system + t_float mu; // step-size parameter (learning rate) + t_float alpha; // small constant to avoid division by zero + + t_canvas *x_canvas; +} t_nlms_tilde; + +static void nlms_tilde_a(t_nlms_tilde *x, t_floatarg f) +{ + x->adapt = (f==0) ? 0 : 1; +} + +static void nlms_tilde_geta(t_nlms_tilde *x) +{ + if(x->adapt==0) + post("nlms~: adaptation is currently OFF"); + else + post("nlms~: adaptation is currently ON"); +} + +static void nlms_tilde_mu(t_nlms_tilde *x, t_floatarg f) +{ + x->mu = f; +} + +static void nlms_tilde_getmu(t_nlms_tilde *x) +{ + post("mu (step-size parameter): %f", x->mu); +} + +static void nlms_tilde_alpha(t_nlms_tilde *x, t_floatarg f) +{ + x->alpha = f; +} + +static void nlms_tilde_getalpha(t_nlms_tilde *x) +{ + post("alpha: %f", x->alpha); +} + +static void nlms_tilde_getN(t_nlms_tilde *x) +{ + post("N (number of coefficients): %d", x->N); +} + +static void nlms_tilde_clear(t_nlms_tilde *x) +{ + int i; + + // clear coefficients + for(i=0; iN; i++) + x->c[i] = 0; + + // clear temp buffer + for(i=0; iN-1; i++) + x->buf[i] = 0; +} + +static void nlms_tilde_init(t_nlms_tilde *x) +{ + int i; + + // set the first coefficient to 1, all others to 0 + // so this is a delay free transmission + x->c[0] = 1; + for(i=1; iN; i++) + x->c[i] = 0; + + // clear temp buffers + for(i=0; iN-1; i++) + x->buf[i] = 0; +} + +static void nlms_tilde_print(t_nlms_tilde *x) +{ + int i; + + // print coefficients + post("\nNr. of coefficients: %d",x->N); + post("coefficients:"); + for(i=0; iN; i++) + post("\t%d: %f",i,x->c[i]); +} + +static void nlms_tilde_write(t_nlms_tilde *x, t_symbol *s) +{ + // make correct path + char filnam[MAXPDSTRING]; + char filename[MAXPDSTRING]; + canvas_makefilename(x->x_canvas, s->s_name, filnam, MAXPDSTRING); + sys_bashfilename(filnam, filename); + + // save to file + adaptation_write(filename, x->N, x->mu, x->c); +} + +static void nlms_tilde_read(t_nlms_tilde *x, t_symbol *s) +{ + // make correct path + char filnam[MAXPDSTRING]; + char filename[MAXPDSTRING]; + canvas_makefilename(x->x_canvas, s->s_name, filnam, MAXPDSTRING); + sys_bashfilename(filnam, filename); + + // read file + adaptation_read(filename, &x->N, &x->mu, x->c, x->buf); +} + +static t_int *nlms_tilde_perform(t_int *w) +{ + t_nlms_tilde *x = (t_nlms_tilde *)(w[1]); + t_sample *x_ = (t_sample *)(w[2]); + t_sample *d_ = (t_sample *)(w[3]); + t_sample *y_ = (t_sample *)(w[4]); + int n = (int)(w[5]); + int i, j, tmp; + t_sample e=0, x_2; + + + for(i=0; itmp[i]=0; + + // y_[i] += x->c[j] * x_[i-j]; + // so lets split in two halfs, so that + // negative indezes get samples from the + // last audioblock (x->buf) ... + tmp = (i+1 - x->N)*(-1); + tmp = tmp<0 ? 0 : tmp; + + for(j=0; jN-tmp; j++) + x->tmp[i] += x->c[j] * x_[i-j]; + + for(j=x->N-tmp; jN; j++) + x->tmp[i] += x->c[j] * x->buf[(i-j)*(-1)-1]; + + if(x->adapt) + { + x_2=0; + + // error computation + e =d_[i] - x->tmp[i]; + + // Normalized LMS Adaptmsation Algorithm + // (split in the same way as above) + // + // c[n] = c[n-1] + mu/(alpha + x'[n]*x[n])*e[n]*x[n] + + // calc x'[n]*x[n] + // TODO: Performance Optimization: save results from the past + // so that this for loop should be obsolet ... + for(j=0; jN-tmp; j++) + x_2 += x_[i-j] * x_[i-j]; + for(j=x->N-tmp; jN; j++) + x_2 += x->buf[(i-j)*(-1)-1] * x->buf[(i-j)*(-1)-1]; + + + for(j=0; jN-tmp; j++) + x->c[j] = x->c[j] + x->mu/(x->alpha+x_2) * x_[i-j] * e; + + for(j=x->N-tmp; jN; j++) + x->c[j] = x->c[j] + x->mu/(x->alpha+x_2) * x->buf[(i-j)*(-1)-1] * e; + } + + //post("%d: in %f, d: %f, out: %f, error: %f, c1:%f, c2:%f", i, x_[i], d_[i], x->tmp[i], e, x->c[0], x->c[1]); + } + + // store last samples for next audiobuffer + for(i=0; iN-1; i++) + x->buf[i] = x_[n-1-i]; + + // now write tmp to outlet + while(n--) + y_[n] = x->tmp[n]; + + return (w+6); +} + +static void nlms_tilde_dsp(t_nlms_tilde *x, t_signal **sp) +{ + // allocate new temp buffer if buffersize changes + if(x->bufsize != sp[0]->s_n) + { + if(sp[0]->s_n < x->N) + post("nlms~ WARNING: buffersize must be bigger than N, you will get wrong results !!!"); + + if(x->tmp) freebytes(x->tmp, sizeof(t_sample) * x->bufsize); + x->tmp = (t_sample *)getbytes(sizeof(t_sample) * sp[0]->s_n); + + x->bufsize = sp[0]->s_n; + } + + dsp_add(nlms_tilde_perform, 5, x, sp[0]->s_vec, sp[1]->s_vec, + sp[2]->s_vec, sp[0]->s_n); +} + +static void nlms_tilde_helper(void) +{ + post("\nnlms~: Adaptive transversal filter using normalized LMS"); + post("INPUT:"); + post("\tinlet1: input signal x[n]"); + post("\tinlet2: desired output signal d[n]"); + post("\tinit_arg1: number of coefficients of the adaptive system"); + post("\tinit_arg2, mu: step-size parameter (learning rate)"); + post("OUTPUT:"); + post("\toutlet1: output signal\n"); +} + +static void *nlms_tilde_new(t_symbol *s, int argc, t_atom *argv) +{ + t_nlms_tilde *x = (t_nlms_tilde *)pd_new(nlms_tilde_class); + int i; + + // default values: + x->N = 8; + x->mu = 0.05; + x->alpha = 0.0001; + x->adapt = 0; + x->tmp = NULL; + x->bufsize = 0; + + switch(argc) + { + case 2: + x->mu = atom_getfloat(argv+1); + case 1: + x->N = atom_getint(argv); + x->N = (x->N<=0) ? 1 : x->N; + } + + // allocate mem and init coefficients + x->c = (t_float *)getbytes(sizeof(t_float) * x->N); + for(i=0; iN; i++) + x->c[i] = 0; + + // allocate mem for temp buffer + x->buf = (t_sample *)getbytes(sizeof(t_sample) * x->N-1); + for(i=0; iN-1; i++) + x->buf[i] = 0; + + inlet_new(&x->x_obj, &x->x_obj.ob_pd, &s_signal, &s_signal); + outlet_new(&x->x_obj, &s_signal); + x->x_canvas = canvas_getcurrent(); + + return (x); +} + +static void nlms_tilde_free(t_nlms_tilde *x) +{ + if(x->c) freebytes(x->c, sizeof(t_float) * x->N); + if(x->buf) freebytes(x->buf, sizeof(t_sample) * x->N-1); + if(x->tmp) freebytes(x->tmp, sizeof(t_sample) * x->bufsize); +} + +void nlms_tilde_setup(void) +{ + nlms_tilde_class = class_new(gensym("nlms~"), (t_newmethod)nlms_tilde_new, + (t_method)nlms_tilde_free, sizeof(t_nlms_tilde), + CLASS_DEFAULT, A_GIMME, 0); + + class_addmethod(nlms_tilde_class, (t_method)nlms_tilde_a, + gensym("adaptation"), A_DEFFLOAT, 0); + class_addmethod(nlms_tilde_class, (t_method)nlms_tilde_geta, + gensym("getadaptation"), 0); + class_addmethod(nlms_tilde_class, (t_method)nlms_tilde_mu, + gensym("mu"), A_DEFFLOAT, 0); + class_addmethod(nlms_tilde_class, (t_method)nlms_tilde_getmu, + gensym("getmu"), 0); + class_addmethod(nlms_tilde_class, (t_method)nlms_tilde_alpha, + gensym("alpha"), A_DEFFLOAT, 0); + class_addmethod(nlms_tilde_class, (t_method)nlms_tilde_getalpha, + gensym("getalpha"), 0); + class_addmethod(nlms_tilde_class, (t_method)nlms_tilde_getN, + gensym("getN"), 0); + class_addmethod(nlms_tilde_class, (t_method)nlms_tilde_init, + gensym("init_unity"), 0); + class_addmethod(nlms_tilde_class, (t_method)nlms_tilde_clear, + gensym("clear"), 0); + class_addmethod(nlms_tilde_class, (t_method)nlms_tilde_print, + gensym("print"), 0); + class_addmethod(nlms_tilde_class, (t_method)nlms_tilde_write, + gensym("write"), A_DEFSYMBOL, 0); + class_addmethod(nlms_tilde_class, (t_method)nlms_tilde_read, + gensym("read"), A_DEFSYMBOL, 0); + + class_addmethod(nlms_tilde_class, (t_method)nlms_tilde_dsp, gensym("dsp"), 0); + CLASS_MAINSIGNALIN(nlms_tilde_class, t_nlms_tilde, f); + + class_addmethod(nlms_tilde_class, (t_method)nlms_tilde_helper, gensym("help"), 0); +} -- cgit v1.2.1