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authorNick White <git@njw.name>2019-04-18 16:31:56 +0100
committerNick White <git@njw.name>2019-04-18 16:31:56 +0100
commite84ba08ef5e3721d6ffa1be46d74851868ef24af (patch)
tree939b4508cffd9e72c164066c55a55fbe9c1ebf1e /cleanup
parentd270536e034d9f218c4e80792abae389028a918a (diff)
Simplify cleanup code
Diffstat (limited to 'cleanup')
-rw-r--r--cleanup/main.go44
1 files changed, 27 insertions, 17 deletions
diff --git a/cleanup/main.go b/cleanup/main.go
index 26655c7..bf94fcf 100644
--- a/cleanup/main.go
+++ b/cleanup/main.go
@@ -39,7 +39,7 @@ func checkwindow(integral [][]uint64, x int, size int, thresh float64) bool {
// divide by 255 as each on pixel has the value of 255
sum := (window.bottomright + window.topleft - window.topright - window.bottomleft) / 255
area := size * height
- proportion := float64(float64(area)/float64(sum)) - 1
+ proportion := float64(area)/float64(sum) - 1
return proportion <= thresh
}
@@ -71,6 +71,30 @@ func cleanimg(img *image.Gray, lowedge int, highedge int) *image.Gray {
return new
}
+// findedges finds the edges of the main content, by moving a window of wsize
+// from the middle of the image to the left and right, stopping when it reaches
+// a point at which there is a lower proportion of black pixels than thresh.
+func findedges(integral [][]uint64, wsize int, thresh float64) (int, int) {
+ maxx := len(integral[0]) - 1
+ var lowedge, highedge int = 0, maxx
+
+ for x := maxx / 2; x < maxx-wsize; x++ {
+ if checkwindow(integral, x, wsize, thresh) {
+ highedge = x + (wsize / 2)
+ break
+ }
+ }
+
+ for x := maxx / 2; x > 0; x-- {
+ if checkwindow(integral, x, wsize, thresh) {
+ lowedge = x - (wsize / 2)
+ break
+ }
+ }
+
+ return lowedge, highedge
+}
+
func main() {
flag.Usage = func() {
fmt.Fprintf(os.Stderr, "Usage: cleanup [-t thresh] [-w winsize] inimg outimg\n")
@@ -98,22 +122,8 @@ func main() {
draw.Draw(gray, b, img, b.Min, draw.Src)
integral := binarize.Integralimg(gray)
- maxx := len(integral[0]) - 1
- var lowedge, highedge int = 0, maxx
- // find right edge
- for x := maxx / 2; x < maxx-*wsize; x++ {
- if checkwindow(integral, x, *wsize, *thresh) {
- highedge = x + (*wsize / 2)
- break
- }
- }
- // find left edge
- for x := maxx / 2; x > 0; x-- {
- if checkwindow(integral, x, *wsize, *thresh) {
- lowedge = x - (*wsize / 2)
- break
- }
- }
+
+ lowedge, highedge := findedges(integral, *wsize, *thresh)
clean := cleanimg(gray, lowedge, highedge)