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-rw-r--r--vendor/github.com/disintegration/imaging/histogram.go52
1 files changed, 0 insertions, 52 deletions
diff --git a/vendor/github.com/disintegration/imaging/histogram.go b/vendor/github.com/disintegration/imaging/histogram.go
deleted file mode 100644
index c547fe82..00000000
--- a/vendor/github.com/disintegration/imaging/histogram.go
+++ /dev/null
@@ -1,52 +0,0 @@
-package imaging
-
-import (
- "image"
- "sync"
-)
-
-// Histogram returns a normalized histogram of an image.
-//
-// Resulting histogram is represented as an array of 256 floats, where
-// histogram[i] is a probability of a pixel being of a particular luminance i.
-func Histogram(img image.Image) [256]float64 {
- var mu sync.Mutex
- var histogram [256]float64
- var total float64
-
- src := newScanner(img)
- if src.w == 0 || src.h == 0 {
- return histogram
- }
-
- parallel(0, src.h, func(ys <-chan int) {
- var tmpHistogram [256]float64
- var tmpTotal float64
- scanLine := make([]uint8, src.w*4)
- for y := range ys {
- src.scan(0, y, src.w, y+1, scanLine)
- i := 0
- for x := 0; x < src.w; x++ {
- s := scanLine[i : i+3 : i+3]
- r := s[0]
- g := s[1]
- b := s[2]
- y := 0.299*float32(r) + 0.587*float32(g) + 0.114*float32(b)
- tmpHistogram[int(y+0.5)]++
- tmpTotal++
- i += 4
- }
- }
- mu.Lock()
- for i := 0; i < 256; i++ {
- histogram[i] += tmpHistogram[i]
- }
- total += tmpTotal
- mu.Unlock()
- })
-
- for i := 0; i < 256; i++ {
- histogram[i] = histogram[i] / total
- }
- return histogram
-}