Canvas Filters

By  on  

Adding filters to images can make them more eye-catching and shareable -- just ask Instagram, Snapchat, Prism, and every other app out there.  A few years back we got the awesome CSS filters feature, allowing us to use a fixed set of filter methods to make our photos beautiful.  Of course CSS filters work on standard HTML elements, not just images, but images provide a better illustration of filter effects.

I was happy to see that browsers have recently implemented those same filters for <canvas> element contents.  Let's start with a snippet from my JavaScript Canvas Image Conversion post, converting an image to canvas:

// Converts image to canvas; returns new canvas element
function convertImageToCanvas(image) {
	var canvas = document.createElement("canvas");
	canvas.width = image.width;
	canvas.height = image.height;
	canvas.getContext("2d").drawImage(image, 0, 0);

	return canvas;
}

var canvas = convertImageToCanvas(document.querySelector('img'));

With a <canvas> element ready, we can then implement CSS filters whenever we'd like:

canvas.getContext('2d').filter = 'blur(5px) opacity(0.6)';

You can see a full list of filters on MDN.  I'm pleased that an API that started with CSS has been mirrored within canvas!

Recent Features

  • By
    Responsive and Infinitely Scalable JS Animations

    Back in late 2012 it was not easy to find open source projects using requestAnimationFrame() - this is the hook that allows Javascript code to synchronize with a web browser's native paint loop. Animations using this method can run at 60 fps and deliver fantastic...

  • By
    Create a CSS Flipping Animation

    CSS animations are a lot of fun; the beauty of them is that through many simple properties, you can create anything from an elegant fade in to a WTF-Pixar-would-be-proud effect. One CSS effect somewhere in between is the CSS flip effect, whereby there's...

Incredible Demos

  • By
    MooTools Font-Size Scroller with Cookie Save

    Providing users as many preferences as possible always puts a smile on the user's face. One of those important preferences is font size. I can see fine but the next guy may have difficulty with the font size I choose. That's why...

  • By
    Create Twitter-Style Dropdowns Using jQuery

    Twitter does some great stuff with JavaScript. What I really appreciate about what they do is that there aren't any epic JS functionalities -- they're all simple touches. One of those simple touches is the "Login" dropdown on their homepage. I've taken...

Discussion

    Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!