function disableImgDragging() {
var images = document.getElementsByTagName("img");
for(var i = 0 ; i < images.length ; i++) {
images[i].classList.add('no-drag');
images[i].setAttribute('no-drag', 'on');
images[i].setAttribute('draggable', 'false');
images[i].addEventListener('dragstart', function( event ) {
event.preventDefault();
}, false);
}
}
disableImgDragging();
