Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
tree: 830f3326b9
Fetching contributors…

Cannot retrieve contributors at this time

217 lines (178 sloc) 5.199 kb
/* Copyright (c) 1997-1999 Miller Puckette.
* For information on usage and redistribution, and for a DISCLAIMER OF ALL
* WARRANTIES, see the file, "LICENSE.txt," in this distribution. */
#include "m_pd.h"
/* --------------------- up/down-sampling --------------------- */
t_int *downsampling_perform_0(t_int *w)
{
t_sample *in = (t_sample *)(w[1]); /* original signal */
t_sample *out = (t_sample *)(w[2]); /* downsampled signal */
int down = (int)(w[3]); /* downsampling factor */
int parent = (int)(w[4]); /* original vectorsize */
int n=parent/down;
while(n--){
*out++=*in;
in+=down;
}
return (w+5);
}
t_int *upsampling_perform_0(t_int *w)
{
t_sample *in = (t_sample *)(w[1]); /* original signal */
t_sample *out = (t_sample *)(w[2]); /* upsampled signal */
int up = (int)(w[3]); /* upsampling factor */
int parent = (int)(w[4]); /* original vectorsize */
int n=parent*up;
t_sample *dummy = out;
while(n--)*out++=0;
n = parent;
out = dummy;
while(n--){
*out=*in++;
out+=up;
}
return (w+5);
}
t_int *upsampling_perform_hold(t_int *w)
{
t_sample *in = (t_sample *)(w[1]); /* original signal */
t_sample *out = (t_sample *)(w[2]); /* upsampled signal */
int up = (int)(w[3]); /* upsampling factor */
int parent = (int)(w[4]); /* original vectorsize */
int i=up;
int n=parent;
t_sample *dum_out = out;
t_sample *dum_in = in;
while (i--) {
n = parent;
out = dum_out+i;
in = dum_in;
while(n--){
*out=*in++;
out+=up;
}
}
return (w+5);
}
t_int *upsampling_perform_linear(t_int *w)
{
t_resample *x= (t_resample *)(w[1]);
t_sample *in = (t_sample *)(w[2]); /* original signal */
t_sample *out = (t_sample *)(w[3]); /* upsampled signal */
int up = (int)(w[4]); /* upsampling factor */
int parent = (int)(w[5]); /* original vectorsize */
int length = parent*up;
int n;
t_sample *fp;
t_sample a=*x->buffer, b=*in;
for (n=0; n<length; n++) {
t_sample findex = (t_sample)(n+1)/up;
int index = findex;
t_sample frac=findex - index;
if (frac==0.)frac=1.;
*out++ = frac * b + (1.-frac) * a;
fp = in+index;
b=*fp;
a=(index)?*(fp-1):a;
}
*x->buffer = a;
return (w+6);
}
/* ----------------------- public -------------------------------- */
/* utils */
void resample_init(t_resample *x)
{
x->method=0;
x->downsample=x->upsample=1;
x->s_n = x->coefsize = x->bufsize = 0;
x->s_vec = x->coeffs = x->buffer = 0;
}
void resample_free(t_resample *x)
{
if (x->s_n) t_freebytes(x->s_vec, x->s_n*sizeof(*x->s_vec));
if (x->coefsize) t_freebytes(x->coeffs, x->coefsize*sizeof(*x->coeffs));
if (x->bufsize) t_freebytes(x->buffer, x->bufsize*sizeof(*x->buffer));
x->s_n = x->coefsize = x->bufsize = 0;
x->s_vec = x->coeffs = x->buffer = 0;
}
/* dsp-adding */
void resample_dsp(t_resample *x,
t_sample* in, int insize,
t_sample* out, int outsize,
int method)
{
if (insize == outsize){
bug("nothing to be done");
return;
}
if (insize > outsize) { /* downsampling */
if (insize % outsize) {
error("bad downsampling factor");
return;
}
switch (method) {
default:
dsp_add(downsampling_perform_0, 4, in, out, insize/outsize, insize);
}
} else { /* upsampling */
if (outsize % insize) {
error("bad upsampling factor");
return;
}
switch (method) {
case 1:
dsp_add(upsampling_perform_hold, 4, in, out, outsize/insize, insize);
break;
case 2:
if (x->bufsize != 1) {
t_freebytes(x->buffer, x->bufsize*sizeof(*x->buffer));
x->bufsize = 1;
x->buffer = t_getbytes(x->bufsize*sizeof(*x->buffer));
}
dsp_add(upsampling_perform_linear, 5, x, in, out, outsize/insize, insize);
break;
default:
dsp_add(upsampling_perform_0, 4, in, out, outsize/insize, insize);
}
}
}
void resamplefrom_dsp(t_resample *x,
t_sample *in,
int insize, int outsize, int method)
{
if (insize==outsize) {
t_freebytes(x->s_vec, x->s_n * sizeof(*x->s_vec));
x->s_n = 0;
x->s_vec = in;
return;
}
if (x->s_n != outsize) {
t_sample *buf=x->s_vec;
t_freebytes(buf, x->s_n * sizeof(*buf));
buf = (t_sample *)t_getbytes(outsize * sizeof(*buf));
x->s_vec = buf;
x->s_n = outsize;
}
resample_dsp(x, in, insize, x->s_vec, x->s_n, method);
return;
}
void resampleto_dsp(t_resample *x,
t_sample *out,
int insize, int outsize, int method)
{
if (insize==outsize) {
if (x->s_n)t_freebytes(x->s_vec, x->s_n * sizeof(*x->s_vec));
x->s_n = 0;
x->s_vec = out;
return;
}
if (x->s_n != insize) {
t_sample *buf=x->s_vec;
t_freebytes(buf, x->s_n * sizeof(*buf));
buf = (t_sample *)t_getbytes(insize * sizeof(*buf));
x->s_vec = buf;
x->s_n = insize;
}
resample_dsp(x, x->s_vec, x->s_n, out, outsize, method);
return;
}
Jump to Line
Something went wrong with that request. Please try again.