Add GetHorizontalWindow function

1 files changed, 12 insertions, 0 deletions

diff --git a/integralimg.go b/integralimg.go
index 5cfbaf3..007e2c6 100644
--- a/integralimg.go
+++ b/integralimg.go
@@ -132,6 +132,18 @@ func (i I) GetVerticalWindow(x, width int) Window {
 	return Window { i[0][x], i[0][maxx], i[maxy][x], i[maxy][maxx], width, maxy }
 }
 
+// GetHorizontalWindow gets the values of the corners of a horizontal
+// slice of an Integral Image, starting at y
+func (i I) GetHorizontalWindow(y, height int) Window {
+	maxy := y + height
+	maxx := len(i[0]) - 1
+	if maxy > len(i) - 1 {
+		maxy = len(i) - 1
+	}
+
+	return Window { i[y][0], i[y][maxx], i[maxy][0], i[maxy][maxx], maxx, height }
+}
+
 // Sum returns the sum of all pixels in a Window
 func (w Window) Sum() uint64 {
 	return w.bottomright + w.topleft - w.topright - w.bottomleft