comparison tools/gauss.c @ 0:5242703e91d3 tip

Initial checkin for AIM92 aimR8.2 (last updated May 1997).
author tomwalters
date Fri, 20 May 2011 15:19:45 +0100
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-1:000000000000 0:5242703e91d3
1 /*
2 gauss.c generate a Gaussian window for a given variance over a given
3 ------- range of standard deviations.
4
5 Output to stdout in binary shorts or floats.
6
7 */
8
9 #include <stdio.h>
10 #include <math.h>
11 #include "options.h"
12 #include "units.h"
13 #include "strmatch.h"
14 #include "sigproc.h"
15
16 char applic[] = "generate a Gaussian window." ;
17
18 static char *helpstr, *debugstr, *sampstr, *varstr ;
19 static char *ranstr, *normstr, *scalestr, *typestr, *sizestr ;
20
21 static Options option[] = {
22 { "help" , "off" , &helpstr , "help" , DEBUG },
23 { "debug" , "off" , &debugstr , "debugging switch" , DEBUG },
24 { "samplerate", "20kHz" , &sampstr , "samplerate " , VAL },
25 { "variance" , "20" , &varstr , "Variance of Gaussian window" , VAL },
26 { "range" , "4" , &ranstr , "Range in standard deviations about mean" , VAL },
27 { "normalize" , "off" , &normstr , "Unit area under curve (unit max if off)" , SETFLAG },
28 { "scale" , "1000" , &scalestr , "Scale factor for output" , VAL },
29 { "type" , "short" , &typestr , "Output datatype (short/float)" , VAL },
30 { "size" , "off" , &sizestr , "Print size of window in samples" , VAL },
31 ( char * ) 0 } ;
32
33
34 int samplerate ;
35
36 float *window ;
37 int points ;
38
39 short *buf ;
40
41
42 main (argc, argv)
43 int argc;
44 char **argv;
45 {
46 float f ;
47
48 getopts( option,argc,argv ) ;
49 if ( !isoff( helpstr ) )
50 helpopts( helpstr, argv[0], applic, option ) ;
51
52 samplerate = to_Hz( sampstr ) ;
53
54 window = gauss_window( to_p( sqrt_units( varstr ), samplerate ), atof( ranstr ), &points ) ;
55
56 if ( ison( normstr ) ) normalize_area( window, points ) ;
57 else if ( !isoff( normstr ) ) {
58 fprintf(stderr,"gauss: unknown normalization [%s]\n", normstr) ;
59 exit( 1 ) ;
60 }
61
62 if ( ison( sizestr ) )
63 printf( "%d\n", points ) ;
64
65 else if ( iststr( typestr, "float" ) ) {
66 scalar( window, points, atof( scalestr ) ) ;
67 fwrite( window, sizeof(float), points, stdout ) ;
68 }
69
70 else if ( iststr( typestr, "short" ) ) {
71 buf = (short *)malloc( points * sizeof(short) ) ;
72 if ( ( f = ftos( window, buf, points, atof( scalestr ) ) ) < 1. )
73 fprintf( stderr,"Warning: 16-bit overflow. Try scale factor < %f\n", f ) ;
74 fwrite( buf, sizeof(short), points, stdout ) ;
75 }
76
77 else
78 fprintf(stderr,"gauss: unknown datatype [%s]\n", typestr) ;
79 }
80
81
82 scalar( y, n, scale )
83 float *y ;
84 int n ;
85 float scale ;
86 {
87 int i ;
88
89 if ( scale != 1. ) {
90 for ( i=0 ; i < n ; i++ )
91 y[i] *= scale ;
92 }
93 }
94
95