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-rw-r--r--cleanup/wipesides.go122
1 files changed, 0 insertions, 122 deletions
diff --git a/cleanup/wipesides.go b/cleanup/wipesides.go
deleted file mode 100644
index ce3b374..0000000
--- a/cleanup/wipesides.go
+++ /dev/null
@@ -1,122 +0,0 @@
-package cleanup
-
-// TODO: add minimum size variable (default ~30%?)
-// TODO: have the integral image specific stuff done by interface functions
-
-import (
- "image"
- "image/color"
-)
-
-type windowslice struct {
- topleft uint64
- topright uint64
- bottomleft uint64
- bottomright uint64
-}
-
-func getwindowslice(i [][]uint64, x int, size int) windowslice {
- maxy := len(i) - 1
- maxx := x + size
- if maxx > len(i[0])-1 {
- maxx = len(i[0]) - 1
- }
-
- return windowslice{i[0][x], i[0][maxx], i[maxy][x], i[maxy][maxx]}
-}
-
-// checkwindow checks the window from x to see whether more than
-// thresh proportion of the pixels are white, if so it returns true.
-func checkwindow(integral [][]uint64, x int, size int, thresh float64) bool {
- height := len(integral)
- window := getwindowslice(integral, x, size)
- // 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(area)/float64(sum) - 1
- return proportion <= thresh
-}
-
-// returns the proportion of the given window that is black pixels
-func proportion(integral [][]uint64, x int, size int) float64 {
- height := len(integral)
- window := getwindowslice(integral, x, size)
- // 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
- return float64(area)/float64(sum) - 1
-}
-
-// findbestedge goes through every vertical line from x to x+w to
-// find the one with the lowest proportion of black pixels.
-func findbestedge(integral [][]uint64, x int, w int) int {
- var bestx int
- var best float64
-
- if w == 1 {
- return x
- }
-
- right := x + w
- for ; x < right; x++ {
- prop := proportion(integral, x, 1)
- if prop > best {
- best = prop
- bestx = x
- }
- }
-
- return bestx
-}
-
-// 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 = findbestedge(integral, x, wsize)
- break
- }
- }
-
- for x := maxx / 2; x > 0; x-- {
- if checkwindow(integral, x, wsize, thresh) {
- lowedge = findbestedge(integral, x, wsize)
- break
- }
- }
-
- return lowedge, highedge
-}
-
-// Wipesides fills the sections of image not within the boundaries
-// of lowedge and highedge with white
-func Wipesides(img *image.Gray, lowedge int, highedge int) *image.Gray {
- b := img.Bounds()
- new := image.NewGray(b)
-
- // set left edge white
- for x := b.Min.X; x < lowedge; x++ {
- for y := b.Min.Y; y < b.Max.Y; y++ {
- new.SetGray(x, y, color.Gray{255})
- }
- }
- // copy middle
- for x := lowedge; x < highedge; x++ {
- for y := b.Min.Y; y < b.Max.Y; y++ {
- new.SetGray(x, y, img.GrayAt(x, y))
- }
- }
- // set right edge white
- for x := highedge; x < b.Max.X; x++ {
- for y := b.Min.Y; y < b.Max.Y; y++ {
- new.SetGray(x, y, color.Gray{255})
- }
- }
-
- return new
-}