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
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
|
// Copyright 2020 Nick White.
// Use of this source code is governed by the GPLv3
// license that can be found in the LICENSE file.
package integral
import (
"image"
"image/draw"
_ "image/png"
"os"
"testing"
)
func TestFromPNG(t *testing.T) {
f, err := os.Open("testdata/in.png")
if err != nil {
t.Fatalf("Could not open file %s: %v\n", "testdata/in.png", err)
}
defer f.Close()
img, _, err := image.Decode(f)
if err != nil {
t.Fatalf("Could not decode image: %v\n", err)
}
b := img.Bounds()
integral := NewImage(b)
draw.Draw(integral, b, img, b.Min, draw.Src)
if !imgsequal(img, integral) {
t.Errorf("Read png image differs to integral image\n")
}
}
func TestSqFromPNG(t *testing.T) {
f, err := os.Open("testdata/in.png")
if err != nil {
t.Fatalf("Could not open file %s: %v\n", "testdata/in.png", err)
}
defer f.Close()
img, _, err := image.Decode(f)
if err != nil {
t.Fatalf("Could not decode image: %v\n", err)
}
b := img.Bounds()
integral := NewSqImage(b)
draw.Draw(integral, b, img, b.Min, draw.Src)
if !imgsequal(img, integral) {
t.Errorf("Read png image differs to square integral image\n")
}
}
func TestSum(t *testing.T) {
f, err := os.Open("testdata/in.png")
if err != nil {
t.Fatalf("Could not open file %s: %v\n", "testdata/in.png", err)
}
defer f.Close()
img, _, err := image.Decode(f)
if err != nil {
t.Fatalf("Could not decode image: %v\n", err)
}
b := img.Bounds()
imgplus := newGray16Plus(b)
integral := NewImage(b)
draw.Draw(imgplus, b, img, b.Min, draw.Src)
draw.Draw(integral, b, img, b.Min, draw.Src)
cases := []struct {
name string
r image.Rectangle
}{
{"fullimage", b},
{"small", image.Rect(1, 1, 5, 5)},
{"toobig", image.Rect(0, 0, 2000, b.Dy())},
{"toosmall", image.Rect(-1, -1, 4, 5)},
{"small2", image.Rect(0, 0, 4, 4)},
}
for _, c := range cases {
t.Run(c.name, func(t *testing.T) {
sumimg := imgplus.sum(c.r)
sumint := integral.Sum(c.r)
if sumimg != sumint {
t.Errorf("Sum of integral image differs to regular image: regular: %d, integral: %d\n", sumimg, sumint)
}
})
}
}
func TestMean(t *testing.T) {
f, err := os.Open("testdata/in.png")
if err != nil {
t.Fatalf("Could not open file %s: %v\n", "testdata/in.png", err)
}
defer f.Close()
img, _, err := image.Decode(f)
if err != nil {
t.Fatalf("Could not decode image: %v\n", err)
}
b := img.Bounds()
imgplus := newGray16Plus(b)
integral := NewImage(b)
draw.Draw(imgplus, b, img, b.Min, draw.Src)
draw.Draw(integral, b, img, b.Min, draw.Src)
cases := []struct {
name string
r image.Rectangle
}{
{"fullimage", b},
{"small", image.Rect(1, 1, 5, 5)},
{"toobig", image.Rect(0, 0, 2000, b.Dy())},
{"toosmall", image.Rect(-1, -1, 4, 5)},
{"small2", image.Rect(0, 0, 4, 4)},
}
for _, c := range cases {
t.Run(c.name, func(t *testing.T) {
meanimg := imgplus.mean(c.r)
meanint := integral.Mean(c.r)
if meanimg != meanint {
t.Errorf("Mean of integral image differs to regular image: regular: %f, integral: %f\n", meanimg, meanint)
}
})
}
}
func imgsequal(img1, img2 image.Image) bool {
b := img1.Bounds()
if !b.Eq(img2.Bounds()) {
return false
}
for y := b.Min.Y; y < b.Max.Y; y++ {
for x := b.Min.X; x < b.Max.X; x++ {
r0, g0, b0, a0 := img1.At(x, y).RGBA()
r1, g1, b1, a1 := img2.At(x, y).RGBA()
if r0 != r1 {
return false
}
if g0 != g1 {
return false
}
if b0 != b1 {
return false
}
if a0 != a1 {
return false
}
}
}
return true
}
type grayPlus struct {
image.Gray16
}
func newGray16Plus(r image.Rectangle) *grayPlus {
var g grayPlus
g.Gray16 = *image.NewGray16(r)
return &g
}
func (i grayPlus) sum(r image.Rectangle) uint64 {
var sum uint64
for y := r.Min.Y; y < r.Max.Y; y++ {
for x := r.Min.X; x < r.Max.X; x++ {
c := i.Gray16At(x, y).Y
sum += uint64(c)
}
}
return sum
}
func (i grayPlus) mean(r image.Rectangle) float64 {
in := r.Intersect(i.Bounds())
return float64(i.sum(r)) / float64(in.Dx()*in.Dy())
}
|