Comic.js
Cartoon style drawing for HTML5 Canvas & Raphael.js & D3.js & SVG.js
Im.js
Image Match - Project to allow compare different images pixel by pixel with good performance
Drawingboard.js
A canvas based drawing app that you can integrate easily on your website.
Vintage JS
vintageJS - add a retro/vintage effect to images using the HTML5 canvas element
Fabric.js
Javascript Canvas Library, SVG-to-Canvas (and canvas-to-SVG) Parser
Scene Graph.js
HTML5 Canvas and Animation Framework
J Query.black and White
Clientside grayscale images on any browser
Soc.js
An easier way to create social icons
Cropper
A simple jQuery image cropping plugin.
FloraJS
FloraJS is a JavaScript framework for simulating natural systems in a web browser.
Rimg
A responsive image solution for browsers that support mediaqueries. Pure javascript and no server-side code.
Paper.js
The Swiss Army Knife of Vector Graphics Scripting – Scriptographer ported to JavaScript and the browser, using HTML5 Canvas. Created by @juerglehni & @jonathanpuckey
jQuery QR Code
qrcode generation standalone (doesn't depend on external services)
Focal Point
A small set of CSS classnames to help keep images cropped on the focal point for responsive designs. Using only HTML/CSS, web authors can specify an image's focal point, which stays as the image's primary focus, while the image's available width changes on responsive webpages. Crop and re-size images depending on available width and let CSS to do all of the work, and without any JavaScript.
Html2canvas
Screenshots with JavaScript
Gif.js
JavaScript GIF encoding library
Joint
JavaScript diagramming library