background-image linear-gradient opacity code example

Example 1: how to give linear transprerancyon background image

background: linear-gradient(to right, rgba(255,255,255,0) 20%,
              rgba(255,255,255,1)), url(http://foo.com/image.jpg);

Example 2: background-image linear-gradient url

body {
    background-image: url("http://www.skrenta.com/images/stackoverflow.jpg"), linear-gradient(red, yellow);
    background-image: url("http://www.skrenta.com/images/stackoverflow.jpg"), -webkit-gradient(linear, left top, left bottom, from(red), to(yellow));
    background-image: url("http://www.skrenta.com/images/stackoverflow.jpg"), -moz-linear-gradient(top, red, yellow);
  }