CasperJS capture screen

screencap.js

var casper = require("casper").create();

// Maximum size of capture
var MAX_WIDTH = 1000,
    MAX_HEIGHT = 1500;

casper.start("http://www.google.com", function() {
    // Figure out how big the BODY element of the document is
    var bounds = this.getElementBounds("body"),
        width = Math.min(bounds.width, MAX_WIDTH),
        height = Math.min(bounds.height, MAX_HEIGHT);

    this.viewport(width, height);

    var image = this.captureBase64("png", {
        top: 0,
        left: 0,
        width: width,
        height: height,
    });

    // @TODO Send the image to exploder
});

casper.run();

// @todo Send the image to exploder

http://stackoverflow.com/a/13320598/330911 :)