diff options
author | Tulir Asokan <tulir@maunium.net> | 2018-04-22 21:25:06 +0300 |
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committer | Tulir Asokan <tulir@maunium.net> | 2018-04-22 21:25:51 +0300 |
commit | 64fa922ec013079f8f0c90fc9e93c56db3611d30 (patch) | |
tree | 7bb9b40f57b8368ef0f5eeccea02d80e54796927 /vendor/github.com/disintegration/imaging/utils.go | |
parent | bfb5f0dd457be326b1ae7638a64d2e79cbace371 (diff) |
Switch to dep
Diffstat (limited to 'vendor/github.com/disintegration/imaging/utils.go')
-rw-r--r-- | vendor/github.com/disintegration/imaging/utils.go | 83 |
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) +} |