CSS Sprite + background-size:cover

Is there a way to use background-size:cover on images loaded with CSS Sprite? Example code:

[class*='img-sprite-']{
   background-image:url('../images/sprite/img.png');
   background-repeat:no-repeat;
   display:block
}

.img-sprite-a1{background-position:-5px 5px}
.img-sprite-a2{background-position:-10px 10px}
.img-sprite-a3{background-position:-15px 15px}
...