Jimp
An image processing library written entirely in JavaScript for Node, with zero external or native dependencies.
Kinetic Js
KineticJS is an HTML5 Canvas JavaScript library that extends the 2D context by enabling canvas interactivity for desktop and mobile applications.
Lightgallery.js
Full featured javascript lightbox gallery. No dependencies.
Vegas
Vegas is a jQuery plugin to add beautiful fullscreen backgrounds to your webpages. It even allows Slideshows.
Isomer
Simple isometric graphics library for HTML5 canvas
Html2canvas
Screenshots with JavaScript
Ejecta
A Fast, Open Source JavaScript, Canvas & Audio Implementation for iOS
Paper.js
The Swiss Army Knife of Vector Graphics Scripting – Scriptographer ported to JavaScript and the browser, using HTML5 Canvas. Created by @juerglehni & @jonathanpuckey
Nivo Slider
The Most Awesome jQuery Image Slider
jQuery QR Code
qrcode generation standalone (doesn't depend on external services)
Jcrop
Jcrop (official) - Image Cropping Plugin for jQuery
Aframe
:a: web framework for building virtual reality experiences.
Processing.js
A port of the Processing visualization language to JavaScript.
Raphael
JavaScript Vector Library
Scenejs
An extensible WebGL-based engine for high-detail 3D visualisation
Photoset Grid
A simple jQuery plugin to arrange images into a flexible grid, based on Tumblr's photoset feature.
jQuery Backstretch
Backstretch is a simple jQuery plugin that allows you to add a dynamically-resized, slideshow-capable background image to any page or element. The image will stretch to fit the page/element, and will automatically resize as the window/element size changes.