fowrdfilt.c

来自「speech signal process tools」· C语言 代码 · 共 34 行

/*
| This material contains proprietary software of Entropic Processing, Inc.
| Any reproduction, distribution, or publication without the the prior
| written permission of Entropic Processing, Inc. is strictly prohibited.
| Any public distribution of copies of this work authorized in writing by
| Entropic Processing, Inc. must bear the notice
|
|              "Copyright 1986 Entropic Processing, Inc."
|
| Written by:  S. Shankar Narayan
|
| Module:	fowrdfilt.c
| 
*/

#ifdef SCCS
static char *sccs_id = "@(#)fowrdfilt.c	1.2 4/21/86 (fowrdfilt.c)";
#endif
	/* perform forward filtering */
float   fowrd_filter (c, state, order, input)
float   c[], state[], input;
int     order;
{
    int     j;
    double   t = input;

    for (j = 1; j <= order; j++)
	t += c[j] * state[j];
    for (j = order; j > 1; j--)
	state[j] = state[j - 1];
    state[1] = t;
    return (t);
}