1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
|
/* $Id$ */
/* Copyright (c) 1995 Oregon Graduate Institute of Science and Technology
* P.O.Box 91000-1000, Portland, OR 97291, USA;
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation, and that the name of O.G.I. not be used in advertising or
* publicity pertaining to distribution of the software without specific,
* written prior permission. O.G.I. makes no representations about the
* suitability of this software for any purpose. It is provided "as is"
* without express or implied warranty.
*
* O.G.I. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
* ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
* O.G.I. BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY
* DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* Author: Shanwei Cen
* Department of Computer Science and Engineering
* email: scen@cse.ogi.edu
*/
#define FILTER_LOWPASS 0
#define FILTER_MEDIAN 1
#define FILTER_AVERAGE 2
typedef struct MedianFilter {
int type;
int * buf;
int nsamples;
int count;
int ptr;
int * stat;
int statsize;
int max, min;
int med; /* median offset to stat */
int below; /* total points below the med entry */
} MedianFilter;
typedef struct LowPassFilter {
int type;
int count;
int maxcount;
double R;
double result;
} LowPassFilter;
typedef struct AverageFilter {
int type;
double * buf;
int nsamples;
int ptr;
double sum;
int count;
} AverageFilter;
typedef union Filter {
int type;
MedianFilter m;
AverageFilter a;
LowPassFilter l;
} Filter;
Filter * NewFilter(int type, int parameter);
Filter * ResetFilter(Filter * f, int parameter);
void FreeFilter(Filter * f);
double DoFilter(Filter *f, double value);
MedianFilter * NewMedianFilter(int nsamples);
MedianFilter * ResetMedianFilter(MedianFilter * f, int nsamples);
void FreeMedianFilter(MedianFilter * f);
double DoMedianFilter(MedianFilter *f, double value);
AverageFilter * NewAverageFilter(int nsamples);
AverageFilter * ResetAverageFilter(AverageFilter * f, int nsamples);
void FreeAverageFilter(AverageFilter * f);
double DoAverageFilter(AverageFilter *f, double value);
LowPassFilter * NewLowPassFilter(double R);
LowPassFilter * ResetLowPassFilter(LowPassFilter * f, double R);
void FreeLowPassFilter(LowPassFilter * f);
double DoLowPassFilter(LowPassFilter *f, double value);
|