PhantomJS Screen Capture

capture.js

/*
 * Usage: phantomjs capture.js [width] [height] [url] [output]
 */

var system = require('system');
var args = system.args;

if (args.length === 5) {
  var width = args[1];
  var height = args[2];
  var url = args[3];
  var output = args[4];
  var page = require('webpage').create();
  page.viewportSize = { width: width, height: height };
  page.open(url, function() {
    page.render(output);
    phantom.exit();
  });
} else {
  console.log("Invalid argument!");
}