58 lines
1.2 KiB
Go
58 lines
1.2 KiB
Go
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package imgkit
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import (
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"image"
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"image/color"
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"golang.org/x/image/draw"
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)
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// Binaryzation process image with threshold value (0-255) and return new image.
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func Binaryzation(src image.Image, threshold uint8) image.Image {
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if threshold < 0 || threshold > 255 {
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threshold = 128
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}
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gray := Gray(src)
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bounds := src.Bounds()
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height, width := bounds.Max.Y-bounds.Min.Y, bounds.Max.X-bounds.Min.X
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for i := 0; i < height; i++ {
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for j := 0; j < width; j++ {
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// var rgb int = int(gray[i][j][0]) + int(gray[i][j][1]) + int(gray[i][j][2])
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if gray.At(j, i).(color.Gray).Y > threshold {
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gray.Set(j, i, color.White)
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} else {
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gray.Set(j, i, color.Black)
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}
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}
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}
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return gray
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}
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func Gray(src image.Image) *image.Gray {
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bounds := src.Bounds()
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height, width := bounds.Max.Y-bounds.Min.Y, bounds.Max.X-bounds.Min.X
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gray := image.NewGray(bounds)
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for i := 0; i < height; i++ {
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for j := 0; j < width; j++ {
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c := color.GrayModel.Convert(src.At(j, i))
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gray.SetGray(j, i, c.(color.Gray))
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}
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}
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return gray
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}
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func Scale(src image.Image, rect image.Rectangle, scale draw.Scaler) image.Image {
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if scale == nil {
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scale = draw.ApproxBiLinear
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}
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dst := image.NewRGBA(rect)
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scale.Scale(dst, rect, src, src.Bounds(), draw.Over, nil)
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return dst
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}
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