Department of Electrical Engineering and Advanced Institute of Manufacturing with High-tech Innovations, National Chung Cheng University, 168 University Rd., Min-Hsiung, Chiayi 621, Taiwan
A defocus blur identification technique based on histogram analysis of a real edge image is presented. The image defocus process of a camera is formulated by incorporating the nonlinear camera response and the intensity-dependent noise model. The histogram matching between the synthesized and real defocused regions is then carried out with intensity-dependent filtering. By iteratively changing the point-spread function parameters, the best blur extent is identified from histogram comparison. We have performed the experiments on both the synthetic and real edge images. The results have demonstrated the robustness and feasibility of the proposed technique.
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Estimation of Blur Extent from Synthetic Defocused Images Generated with Different Parameter Settingsa
Pillbox radius
A
B
C
A
B
C
A
B
C
A
B
C
A
B
C
1.0
39
39
40
59
59
59
80
79
80
99
100
99
119
119
119
1.5
40
39
40
60
59
59
80
79
80
99
99
100
119
118
119
2.0
39
39
40
60
59
59
79
78
80
99
97
99
119
117
120
2.5
39
39
40
59
58
60
79
77
79
99
96
99
119
118
120
1.0
40
40
40
59
59
59
79
79
79
100
100
100
120
119
119
1.5
39
39
40
59
59
59
79
79
80
99
98
99
119
119
120
2.0
39
39
39
59
58
60
79
77
80
98
97
99
118
117
120
2.5
39
38
39
59
57
59
78
76
80
98
96
99
118
114
119
1.0
40
40
40
60
60
60
80
80
80
100
99
100
120
120
120
1.5
39
39
39
59
58
60
79
78
79
100
98
99
119
118
119
2.0
39
38
40
59
57
60
78
77
80
98
96
100
118
115
120
2.5
38
38
39
58
56
59
78
76
80
98
94
100
117
112
119
1.0
40
40
40
59
59
60
80
80
80
99
99
100
120
120
119
1.5
39
39
40
59
59
60
80
79
80
99
98
99
119
118
120
2.0
39
39
40
59
58
60
79
77
79
98
96
100
119
115
120
2.5
39
38
39
58
57
59
78
76
80
98
94
100
117
113
120
(Blur radius: , 60, 80, 100, and 120; Gaussian noise variance: , , , and ; nonlinear camera response parameter : 1.0, 1.5, 2.0, and 2.5). Column A: estimated with intensity-dependent filtering and unknown . Column B: estimated without intensity-dependent filtering and with unknown . Column C: estimated with intensity-dependent filtering and known .
Table 2.
Estimation of Defocus Blur and Nonlinear Response Parameter for the Defocused Images Captured with F-5.6 and ISO-100a
Image #
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
hm-idfn
107
104
101
96
93
90
87
84
82
78
75
73
70
67
65
61
59
56
1.8
1.8
1.8
1.8
1.7
1.8
1.8
1.7
1.8
1.8
1.7
1.7
1.8
1.8
1.8
1.6
1.7
1.7
hm
106
104
100
94
92
89
86
83
81
77
75
72
69
67
64
61
58
56
Image #
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
hm-idfn
54
51
50
47
44
41
38
35
32
29
26
24
21
18
15
9
6
1
1.7
1.6
1.7
1.7
1.7
1.6
1.6
1.6
1.6
1.5
1.6
1.5
1.5
1.5
1.6
1.1
1.0
0.9
hm
52
50
49
46
43
41
38
35
32
29
26
23
31
18
15
9
6
1
“hm-idfn” and “hm” list the blur radius estimated using histogram matching with and without intensity-dependent filtering, respectively.
Table 3.
Estimation of Defocus Blur and Nonlinear Response Parameter for the Defocused Images captured with F-10 and ISO-100a
Image #
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
hm-idfn
62
61
59
57
56
54
52
50
49
47
46
44
41
40
39
36
35
33
2.1
2.0
2.1
2.1
2.1
2.0
2.0
2.0
2.0
2.1
2.2
2.1
1.8
2.1
2.0
1.9
1.9
1.9
hm
61
59
58
55
55
53
51
50
48
47
45
43
40
40
38
35
34
32
Image #
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
hm-idfn
31
29
28
26
24
23
21
20
18
16
14
12
10
9
7
5
4
1
1.9
1.8
1.9
1.8
1.6
1.8
1.8
1.7
1.5
1.8
1.8
1.8
2.0
2.1
2.2
1.9
1.6
1.5
hm
30
29
27
26
24
22
21
19
18
16
14
12
10
8
7
5
4
1
“hm-idfn” and “hm” list the blur radius estimated using histogram matching with and without intensity-dependent filtering, respectively.
Table 4.
Estimation of Defocus Blur and Nonlinear Response Parameter for the Defocused Images Captured with F-18 and ISO-100a
Image #
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
hm-idfn
33
33
32
31
30
29
29
27
27
25
24
24
23
22
22
21
19
18
1.7
1.8
1.8
1.8
1.8
1.8
1.7
1.7
1.7
1.7
1.6
1.7
1.6
1.6
1.7
1.8
1.7
1.7
hm
33
32
32
31
30
29
29
26
26
25
24
24
23
22
21
20
19
18
Image #
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
hm-idfn
17
16
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
1.7
1.6
1.6
1.4
1.5
1.4
1.5
1.6
1.5
1.6
1.5
1.4
1.4
1.0
0.7
0.8
0.6
2.6
hm
17
16
15
15
13
13
12
11
10
9
8
7
6
5
5
3
2
1
“hm-idfn” and “hm” list the blur radius estimated using histogram matching with and without intensity-dependent filtering, respectively.
Table 5.
Estimation of Defocus Blur for the Images Captured with F-5.6 and ISO-3200a
Image #
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
hm-idfn
103
99
96
95
91
88
86
83
81
77
74
73
70
66
63
60
59
55
hm-idf
103
99
97
95
91
88
86
83
80
77
74
73
69
66
63
60
59
55
hm
102
98
95
94
89
87
85
82
79
76
74
73
68
66
62
60
58
54
Image #
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
hm-idfn
52
49
47
43
41
38
35
32
29
27
23
20
18
15
12
9
6
3
hm-idf
52
49
47
43
40
38
35
32
29
27
23
20
18
15
12
9
6
3
hm
51
48
46
43
40
38
34
32
29
27
23
20
18
15
12
9
6
3
“hm-idfn” lists the blur radius estimated with intensity-dependent filtering and intensity-dependent noise model. “hm-idf” lists the blur radius estimated with intensity-dependent filtering and constant noise model. “hm” lists the blur radius estimated without intensity-dependent filtering and with constant noise model.
Table 6.
Estimation of Defocus Blur for the Images cCaptured with F-10 and ISO-3200
Image #
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
hm-idfn
62
59
59
57
56
53
52
50
48
45
45
43
41
39
37
36
34
33
hm-idf
62
59
59
57
55
53
52
50
48
45
45
43
41
39
37
36
34
32
hm
62
59
58
56
55
53
51
49
48
45
45
42
41
39
37
36
34
32
Image #
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
hm-idfn
31
29
27
25
23
22
20
18
17
16
14
13
11
9
7
6
4
3
hm-idf
31
28
26
25
23
21
20
18
17
16
14
12
11
8
7
5
3
1
hm
31
29
26
25
23
21
20
18
17
15
14
12
10
9
7
5
3
2
Table 7.
Estimation of Defocus Blur for the Images Captured with F-18 and ISO-3200
Image #
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
hm-idfn
32
31
30
29
28
27
26
26
25
23
23
22
21
20
19
18
17
16
hm-idf
31
31
30
29
28
27
26
25
24
23
22
22
21
20
19
18
17
16
hm
31
31
30
29
28
27
26
25
24
23
22
22
21
20
19
18
17
16
Image #
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
hm-idfn
16
15
14
13
12
11
10
9
8
7
6
6
5
4
3
3
2
2
hm-idf
15
14
14
12
12
11
9
9
8
7
6
5
4
3
3
2
1
1
hm
16
15
14
13
11
11
10
9
8
7
6
5
4
4
3
2
2
1
Table 8.
Blur Extents of the LIVE Database Images and Our Captured Defocused Imagesa
Index #
bikes
buildings
caps
house
lighthouse
monarch
0
2.33
0.00
0.59
1.00
0.50
1.00
1
2.33
0.00
0.76
1.67
0.50
1.50
2
2.33
0.33
1.41
2.00
2.50
3.00
3
3.00
0.67
2.76
2.00
2.50
3.00
4
3.67
1.33
5.29
3.00
4.50
4.00
5
7.67
4.00
7.88
4.33
11.00
3.50
Index #
paintedhouse
parrots
plane
womanhat
book
cartridge
0
5.50
1.86
0.78
2.75
1.55
2.27
1
5.25
2.14
1.44
3.13
2.47
3.18
2
6.75
2.43
1.33
4.63
3.34
4.45
3
7.00
3.57
2.33
4.75
4.24
5.55
4
7.25
4.86
6.11
5.75
5.11
6.27
5
12.50
9.00
6.56
7.00
5.95
7.27
Index number 0 indicates the reference or focused image, and the images generated or captured with more severe blur are those with higher index numbers.
Tables (8)
Table 1.
Estimation of Blur Extent from Synthetic Defocused Images Generated with Different Parameter Settingsa
Pillbox radius
A
B
C
A
B
C
A
B
C
A
B
C
A
B
C
1.0
39
39
40
59
59
59
80
79
80
99
100
99
119
119
119
1.5
40
39
40
60
59
59
80
79
80
99
99
100
119
118
119
2.0
39
39
40
60
59
59
79
78
80
99
97
99
119
117
120
2.5
39
39
40
59
58
60
79
77
79
99
96
99
119
118
120
1.0
40
40
40
59
59
59
79
79
79
100
100
100
120
119
119
1.5
39
39
40
59
59
59
79
79
80
99
98
99
119
119
120
2.0
39
39
39
59
58
60
79
77
80
98
97
99
118
117
120
2.5
39
38
39
59
57
59
78
76
80
98
96
99
118
114
119
1.0
40
40
40
60
60
60
80
80
80
100
99
100
120
120
120
1.5
39
39
39
59
58
60
79
78
79
100
98
99
119
118
119
2.0
39
38
40
59
57
60
78
77
80
98
96
100
118
115
120
2.5
38
38
39
58
56
59
78
76
80
98
94
100
117
112
119
1.0
40
40
40
59
59
60
80
80
80
99
99
100
120
120
119
1.5
39
39
40
59
59
60
80
79
80
99
98
99
119
118
120
2.0
39
39
40
59
58
60
79
77
79
98
96
100
119
115
120
2.5
39
38
39
58
57
59
78
76
80
98
94
100
117
113
120
(Blur radius: , 60, 80, 100, and 120; Gaussian noise variance: , , , and ; nonlinear camera response parameter : 1.0, 1.5, 2.0, and 2.5). Column A: estimated with intensity-dependent filtering and unknown . Column B: estimated without intensity-dependent filtering and with unknown . Column C: estimated with intensity-dependent filtering and known .
Table 2.
Estimation of Defocus Blur and Nonlinear Response Parameter for the Defocused Images Captured with F-5.6 and ISO-100a
Image #
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
hm-idfn
107
104
101
96
93
90
87
84
82
78
75
73
70
67
65
61
59
56
1.8
1.8
1.8
1.8
1.7
1.8
1.8
1.7
1.8
1.8
1.7
1.7
1.8
1.8
1.8
1.6
1.7
1.7
hm
106
104
100
94
92
89
86
83
81
77
75
72
69
67
64
61
58
56
Image #
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
hm-idfn
54
51
50
47
44
41
38
35
32
29
26
24
21
18
15
9
6
1
1.7
1.6
1.7
1.7
1.7
1.6
1.6
1.6
1.6
1.5
1.6
1.5
1.5
1.5
1.6
1.1
1.0
0.9
hm
52
50
49
46
43
41
38
35
32
29
26
23
31
18
15
9
6
1
“hm-idfn” and “hm” list the blur radius estimated using histogram matching with and without intensity-dependent filtering, respectively.
Table 3.
Estimation of Defocus Blur and Nonlinear Response Parameter for the Defocused Images captured with F-10 and ISO-100a
Image #
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
hm-idfn
62
61
59
57
56
54
52
50
49
47
46
44
41
40
39
36
35
33
2.1
2.0
2.1
2.1
2.1
2.0
2.0
2.0
2.0
2.1
2.2
2.1
1.8
2.1
2.0
1.9
1.9
1.9
hm
61
59
58
55
55
53
51
50
48
47
45
43
40
40
38
35
34
32
Image #
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
hm-idfn
31
29
28
26
24
23
21
20
18
16
14
12
10
9
7
5
4
1
1.9
1.8
1.9
1.8
1.6
1.8
1.8
1.7
1.5
1.8
1.8
1.8
2.0
2.1
2.2
1.9
1.6
1.5
hm
30
29
27
26
24
22
21
19
18
16
14
12
10
8
7
5
4
1
“hm-idfn” and “hm” list the blur radius estimated using histogram matching with and without intensity-dependent filtering, respectively.
Table 4.
Estimation of Defocus Blur and Nonlinear Response Parameter for the Defocused Images Captured with F-18 and ISO-100a
Image #
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
hm-idfn
33
33
32
31
30
29
29
27
27
25
24
24
23
22
22
21
19
18
1.7
1.8
1.8
1.8
1.8
1.8
1.7
1.7
1.7
1.7
1.6
1.7
1.6
1.6
1.7
1.8
1.7
1.7
hm
33
32
32
31
30
29
29
26
26
25
24
24
23
22
21
20
19
18
Image #
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
hm-idfn
17
16
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
1.7
1.6
1.6
1.4
1.5
1.4
1.5
1.6
1.5
1.6
1.5
1.4
1.4
1.0
0.7
0.8
0.6
2.6
hm
17
16
15
15
13
13
12
11
10
9
8
7
6
5
5
3
2
1
“hm-idfn” and “hm” list the blur radius estimated using histogram matching with and without intensity-dependent filtering, respectively.
Table 5.
Estimation of Defocus Blur for the Images Captured with F-5.6 and ISO-3200a
Image #
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
hm-idfn
103
99
96
95
91
88
86
83
81
77
74
73
70
66
63
60
59
55
hm-idf
103
99
97
95
91
88
86
83
80
77
74
73
69
66
63
60
59
55
hm
102
98
95
94
89
87
85
82
79
76
74
73
68
66
62
60
58
54
Image #
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
hm-idfn
52
49
47
43
41
38
35
32
29
27
23
20
18
15
12
9
6
3
hm-idf
52
49
47
43
40
38
35
32
29
27
23
20
18
15
12
9
6
3
hm
51
48
46
43
40
38
34
32
29
27
23
20
18
15
12
9
6
3
“hm-idfn” lists the blur radius estimated with intensity-dependent filtering and intensity-dependent noise model. “hm-idf” lists the blur radius estimated with intensity-dependent filtering and constant noise model. “hm” lists the blur radius estimated without intensity-dependent filtering and with constant noise model.
Table 6.
Estimation of Defocus Blur for the Images cCaptured with F-10 and ISO-3200
Image #
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
hm-idfn
62
59
59
57
56
53
52
50
48
45
45
43
41
39
37
36
34
33
hm-idf
62
59
59
57
55
53
52
50
48
45
45
43
41
39
37
36
34
32
hm
62
59
58
56
55
53
51
49
48
45
45
42
41
39
37
36
34
32
Image #
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
hm-idfn
31
29
27
25
23
22
20
18
17
16
14
13
11
9
7
6
4
3
hm-idf
31
28
26
25
23
21
20
18
17
16
14
12
11
8
7
5
3
1
hm
31
29
26
25
23
21
20
18
17
15
14
12
10
9
7
5
3
2
Table 7.
Estimation of Defocus Blur for the Images Captured with F-18 and ISO-3200
Image #
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
hm-idfn
32
31
30
29
28
27
26
26
25
23
23
22
21
20
19
18
17
16
hm-idf
31
31
30
29
28
27
26
25
24
23
22
22
21
20
19
18
17
16
hm
31
31
30
29
28
27
26
25
24
23
22
22
21
20
19
18
17
16
Image #
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
hm-idfn
16
15
14
13
12
11
10
9
8
7
6
6
5
4
3
3
2
2
hm-idf
15
14
14
12
12
11
9
9
8
7
6
5
4
3
3
2
1
1
hm
16
15
14
13
11
11
10
9
8
7
6
5
4
4
3
2
2
1
Table 8.
Blur Extents of the LIVE Database Images and Our Captured Defocused Imagesa
Index #
bikes
buildings
caps
house
lighthouse
monarch
0
2.33
0.00
0.59
1.00
0.50
1.00
1
2.33
0.00
0.76
1.67
0.50
1.50
2
2.33
0.33
1.41
2.00
2.50
3.00
3
3.00
0.67
2.76
2.00
2.50
3.00
4
3.67
1.33
5.29
3.00
4.50
4.00
5
7.67
4.00
7.88
4.33
11.00
3.50
Index #
paintedhouse
parrots
plane
womanhat
book
cartridge
0
5.50
1.86
0.78
2.75
1.55
2.27
1
5.25
2.14
1.44
3.13
2.47
3.18
2
6.75
2.43
1.33
4.63
3.34
4.45
3
7.00
3.57
2.33
4.75
4.24
5.55
4
7.25
4.86
6.11
5.75
5.11
6.27
5
12.50
9.00
6.56
7.00
5.95
7.27
Index number 0 indicates the reference or focused image, and the images generated or captured with more severe blur are those with higher index numbers.