blob: b4f3c621ac9f055fdaf3e3ae6d442f8ce76741c4 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
|
title: How to Downsize Images and Keep Them Sharp
date: 20140731 13:27:28
tags: #gimp #photos #webdev
When you size down an image you may get moires or jagged edges due to spatial frequency folding. The solution is to pre-blur the picture before sizing down. The rule is simple, if you size down by X, pre-blur with a Gaussian blur with a radius of X. For example, if you take an image from from 2000px to 400 (1:5), you would use a 5px blur radius.
Then resize your image with scale image (resize in PS) and apply smart sharpen to sharpen up the details.
This works because that pre-blur step (provided you do it right, using just enough, but not too much) doesn't end up softening the result any more than a direct downscale. If done correctly it removes information that will be lost in the resize anyway.
based on: http://gimpforums.com/thread-image-quality-and-resizing
|
