Brightness and Contrast for a canvas image with javascript

Question

I have an image in a tag

var img = new Image();
ctx.drawImage(img,0,0,img.width,img.height);
ecc...

How is possible to change the Brightness

Answer 1

In my experience, fabric.js is the best javascript library for performing this. Check out Fabric JS and how to do image filtering at: http://fabricjs.com/image-filters