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Diffstat (limited to 'integralimg.go')
-rw-r--r--integralimg.go20
1 files changed, 16 insertions, 4 deletions
diff --git a/integralimg.go b/integralimg.go
index 53aec13..922b1ce 100644
--- a/integralimg.go
+++ b/integralimg.go
@@ -142,24 +142,36 @@ func highest(a, b int) int {
func (i Image) topLeft(r image.Rectangle) uint64 {
x := highest(r.Min.X, 0)
y := highest(r.Min.Y, 0)
+ if x == 0 || y == 0 {
+ return 0
+ }
return i[y][x]
}
func (i Image) topRight(r image.Rectangle) uint64 {
- x := lowest(r.Max.X, i.Bounds().Dx() - 1)
+ x := lowest(r.Max.X - 1, i.Bounds().Dx() - 1)
y := highest(r.Min.Y, 0)
+ if x == 0 || y == 0 {
+ return 0
+ }
return i[y][x]
}
func (i Image) bottomLeft(r image.Rectangle) uint64 {
x := highest(r.Min.X, 0)
- y := lowest(r.Max.Y, i.Bounds().Dy() - 1)
+ y := lowest(r.Max.Y - 1, i.Bounds().Dy() - 1)
+ if x == 0 || y == 0 {
+ return 0
+ }
return i[y][x]
}
func (i Image) bottomRight(r image.Rectangle) uint64 {
- x := lowest(r.Max.X, i.Bounds().Dx() - 1)
- y := lowest(r.Max.Y, i.Bounds().Dy() - 1)
+ x := lowest(r.Max.X - 1, i.Bounds().Dx() - 1)
+ y := lowest(r.Max.Y - 1, i.Bounds().Dy() - 1)
+ if x == 0 || y == 0 {
+ return 0
+ }
return i[y][x]
}