69 lines
1.9 KiB
Go
69 lines
1.9 KiB
Go
// magickwand.go
|
|
package main
|
|
|
|
import (
|
|
"math"
|
|
|
|
"gopkg.in/gographics/imagick.v2/imagick"
|
|
)
|
|
|
|
/*resizeImage() mw fullsize image
|
|
newwidth, newheight = size to be resized to
|
|
keepSpecSize = return image with exactly the size specified or just the size of the resized image
|
|
center = senter the image
|
|
*/
|
|
func resizeImage(mw *imagick.MagickWand, newWidth, newHeight int, keepSpecSize, center bool) (resmw *imagick.MagickWand) {
|
|
var (
|
|
width, height, origHeight, origWidth int
|
|
)
|
|
origHeight = int(mw.GetImageHeight())
|
|
origWidth = int(mw.GetImageWidth())
|
|
|
|
//check if requested size is the same as current size
|
|
if (origHeight != newHeight) || (origWidth != newWidth) {
|
|
// width / height * newheight = newwidth
|
|
if (round((float64(origWidth) / float64(origHeight)) * float64(newHeight))) <= newWidth {
|
|
width = round((float64(origWidth) / float64(origHeight)) * float64(newHeight))
|
|
height = newHeight
|
|
} else {
|
|
// height / width * newwidth = newheight
|
|
height = round((float64(origHeight) / float64(origWidth)) * float64(newWidth))
|
|
width = newWidth
|
|
}
|
|
} else {
|
|
height = newHeight
|
|
width = newWidth
|
|
}
|
|
|
|
//new magickwand for resized image
|
|
resmw = imagick.NewMagickWand()
|
|
|
|
if !keepSpecSize {
|
|
resmw.NewImage(uint(width), uint(height), imagick.NewPixelWand())
|
|
center = false
|
|
} else {
|
|
//blank image
|
|
resmw.NewImage(uint(newWidth), uint(newHeight), imagick.NewPixelWand())
|
|
if center {
|
|
err = mw.ResizeImage(uint(width), uint(height), imagick.FILTER_LANCZOS, 1)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
//centers image
|
|
resmw.CompositeImage(mw, imagick.COMPOSITE_OP_SRC_OVER, round(float64(newWidth-width)/float64(2)), round(float64(newHeight-height)/float64(2)))
|
|
} else {
|
|
resmw.CompositeImage(mw, imagick.COMPOSITE_OP_SRC_OVER, 0, 0)
|
|
}
|
|
}
|
|
mw.Destroy()
|
|
return resmw
|
|
|
|
}
|
|
|
|
func round(a float64) int {
|
|
if a < 0 {
|
|
return int(math.Ceil(a - 0.5))
|
|
}
|
|
return int(math.Floor(a + 0.5))
|
|
}
|