I've been looking for a solution to create a smooth circular image crop, but to my surprise it didn't exist!
You can use Image Magick to create something like this, but alas installing Image Magick is a huge hassle, ergo I'm using PHP GD since it's avalaible in most PHP library.
Tested on
- IE7 - IE10, Windows 8
- Chrome 25.0.1364.99
- Safari Version 6.0.2 (8536.26.17)
- Opera/9.80 (Macintosh; Intel Mac OS X 10.8.2) Presto/2.12.388 Version/12.14
- FF 18.0.2
- iPhone/iPad/Android (I forgot which version :p ..will update later)