How to show animated image from PNG image using javascript? [ like gmail ]

Question

First of all,check out this image

Gmail uses this image to display the

Answer 1

CSS @keyframes can be used in this case

@keyframes smile {
    0% { background-postiion: 0 -16px;}
    5% { background-postiion: 0 -32px;}
    10% { background-postiion: 0 -48px;}
    /*...etc*/
}