jQuery maskImage plugin

I had a need today to write some code which involved masking one image with another, dynamically.

There is no simple way to do this in JavaScript. The nearest I came to finding working code online that does it was edge.js, but that’s not free.

So, I wrote my own.

demo

Download: zip (25k), bz2 (24k)

In the demo, what’s happening is that an image such as this:

is being used as a mask for another image:

to create a masked image:

For Firefox and Chrome and other recent browsers, it works using pure JavaScript (even works on the iPhone).

For Internet Explorer (sigh) you need to do a little bit of server-side setup.

Basically, on the server-side, make sure you have PHP installed, with the iMagick extension, then make the ‘cache’ directory writable by the server.

To use, insert an image into your document:

[html]
<img id="image-id" src="an-image.png" alt="" />
[/html]

And then apply the mask using jQuery:

[javascript]
$(‘#image-id’).maskImage({src:"the-mask.png"});
[/javascript]

Simple, innit! That’s a few hours of my own life dedicated to saving a few minutes of yours 😉