Edit in JSFiddle

h1 {
    color: transparent;
    background: url(http://placekitten.com/300/300) repeat;
    -webkit-background-clip: text;
    -moz-background-clip: text;
    -ms-background-clip: text;
    -o-background-clip: text;
    background-clip: text;
    font-size: 10rem;
    margin: 0;
}