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path: root/vendor/github.com/disintegration/imaging/utils.go
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-rw-r--r--vendor/github.com/disintegration/imaging/utils.go83
1 files changed, 83 insertions, 0 deletions
diff --git a/vendor/github.com/disintegration/imaging/utils.go b/vendor/github.com/disintegration/imaging/utils.go
new file mode 100644
index 0000000..3b6ad2e
--- /dev/null
+++ b/vendor/github.com/disintegration/imaging/utils.go
@@ -0,0 +1,83 @@
+package imaging
+
+import (
+ "image"
+ "runtime"
+ "sync"
+)
+
+// parallel processes the data in separate goroutines.
+func parallel(start, stop int, fn func(<-chan int)) {
+ count := stop - start
+ if count < 1 {
+ return
+ }
+
+ procs := runtime.GOMAXPROCS(0)
+ if procs > count {
+ procs = count
+ }
+
+ c := make(chan int, count)
+ for i := start; i < stop; i++ {
+ c <- i
+ }
+ close(c)
+
+ var wg sync.WaitGroup
+ for i := 0; i < procs; i++ {
+ wg.Add(1)
+ go func() {
+ defer wg.Done()
+ fn(c)
+ }()
+ }
+ wg.Wait()
+}
+
+// absint returns the absolute value of i.
+func absint(i int) int {
+ if i < 0 {
+ return -i
+ }
+ return i
+}
+
+// clamp rounds and clamps float64 value to fit into uint8.
+func clamp(x float64) uint8 {
+ v := int64(x + 0.5)
+ if v > 255 {
+ return 255
+ }
+ if v > 0 {
+ return uint8(v)
+ }
+ return 0
+}
+
+func reverse(pix []uint8) {
+ if len(pix) <= 4 {
+ return
+ }
+ i := 0
+ j := len(pix) - 4
+ for i < j {
+ pix[i+0], pix[j+0] = pix[j+0], pix[i+0]
+ pix[i+1], pix[j+1] = pix[j+1], pix[i+1]
+ pix[i+2], pix[j+2] = pix[j+2], pix[i+2]
+ pix[i+3], pix[j+3] = pix[j+3], pix[i+3]
+ i += 4
+ j -= 4
+ }
+}
+
+func toNRGBA(img image.Image) *image.NRGBA {
+ if img, ok := img.(*image.NRGBA); ok {
+ return &image.NRGBA{
+ Pix: img.Pix,
+ Stride: img.Stride,
+ Rect: img.Rect.Sub(img.Rect.Min),
+ }
+ }
+ return Clone(img)
+}