webkit transitions

I have a <div id=”pic”> in which I change the background image using this JavaScript:

document.getElementById(‘pic’).style.backgroundImage = url(newpic.jpg);

I am trying to figure out if I can use CSS webkit transitions to easily fade one image into another.

I was thinking I just needed some CSS like . . .

#pic { -webkit-transition: all 1s ease-in-out; }

But no luck.

Also in #CSS _↴