You can use FileReader web-api object for this, see this example:
In Html code:
<input id="src" type="file" onchange="fileChange()" />
<img id="target" />
In javascript:
function fileChange(){
var src = document.getElementById("src");
var target = document.getElementById("target");
showImage(src,target);
}
function showImage(src,target) {
var fr=new FileReader();
fr.onload = function(e) { target.src = this.result; };
src.addEventListener("change",function() {
fr.readAsDataURL(src.files[0]);
});
}