svg filter

HTML

<div id='svgContainer' style="width: 65%; ></div>

JavaScript

var container = document.getElementById("svgContainer");
var mySvg = document.createElementNS("http://www.w3.org/2000/svg", "svg");
mySvg.setAttribute("version", "1.1");
container.appendChild(mySvg);

var obj = document.createElementNS("http://www.w3.org/2000/svg", "rect");
obj.setAttribute("width", "90");
obj.setAttribute("height", "90");

var defs = document.createElementNS("http://www.w3.org/2000/svg", "defs");

var filter = document.createElementNS("http://www.w3.org/2000/svg", "filter");
filter.setAttribute("id","f1");
filter.setAttribute("x","0");
filter.setAttribute("y","0");

var gaussianFilter = document.createElementNS("http://www.w3.org/2000/svg", "feGaussianBlur");
gaussianFilter.setAttribute("in","SourceGraphic");
gaussianFilter.setAttribute("stdDeviation","15");

filter.appendChild(gaussianFilter);
defs.appendChild(filter);
mySvg.appendChild(defs);    
obj.setAttribute("filter","url(#f1)");

mySvg.appendChild(obj);