When you put a UIImage into a UIImageView that is smaller than the view, and the content mode of the view is ScaleToFit, iOS enlarges the bitmap, as expected. What I have never expected is that it blurs the edges of the pixels it has scaled-up. I can see this might be a nice touch if you're looking at photographs, but in many other cases I want to see those nasty, hard, straight edges!
Does anyone know how you can configure a UIImage or UIImageView to enlarge with sharp pixel edges? That is: Let it look pixellated, not blurred.
Thanks!
If you want to scale up any image in UIImageView with sharpen edge, use the following property of CALayer.
imageview.layer.magnificationFilter = kCAFilterNearest;
It seems that magnificationFilter affects an interpolation method of contents of UIView. I recommend you to read an explanation of the property in CALayer.h.
/* The filter types to use when rendering the `contents' property of
* the layer. The minification filter is used when to reduce the size
* of image data, the magnification filter to increase the size of
* image data. Currently the allowed values are `nearest' and `linear'.
* Both properties default to `linear'. */
@property(copy) NSString *minificationFilter, *magnificationFilter;
I hope that my answer is useful for you.
