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@ericdke

ericdke/resizeNSImage.swift

Last active March 3, 2023 13:47
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Resize NSImage
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resizeNSImage.swift
func resize(image: NSImage, w: Int, h: Int) -> NSImage {
var destSize = NSMakeSize(CGFloat(w), CGFloat(h))
var newImage = NSImage(size: destSize)
newImage.lockFocus()
image.drawInRect(NSMakeRect(0, 0, destSize.width, destSize.height), fromRect: NSMakeRect(0, 0, image.size.width, image.size.height), operation: NSCompositingOperation.CompositeSourceOver, fraction: CGFloat(1))
newImage.unlockFocus()
newImage.size = destSize
return NSImage(data: newImage.TIFFRepresentation!)!
}
@ysoftware
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This doesn't work right.
I input 200x200 and it returns image of size 400x400.
https://gist.github.com/raphaelhanneken/cb924aa280f4b9dbb480
Found a better solution here.

@PaulMcClernan
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PaulMcClernan commented Mar 3, 2023 •
edited
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I input 200x200 and it returns image of size 400x400.

Just to clarify for anyone here looking for the reason for this (as opposed to Swift code solution),
this is due to newer 'Retina' displays which have double the pixel density (144px per inch, vs. older screen resolution of 72px), there may be higher screen resolutions in the future with 4K, 6K, and 8K screens becoming more widely available.

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