Can be done however you may run into some problems with cross browser support.
See older answer on stack overflow
-webkit-mask-image:-webkit-gradient(linear, left top, left bottom,from(rgba(0,0,0,1)), to(rgba(0,0,0,0)))
<html>
<style type='text/css'>
div, img { position:absolute; top:0; left:0; width:250px; height:250px; }
img {
-webkit-mask-image:-webkit-gradient(linear, left top, left bottom, from(rgba(0,0,0,1)), to(rgba(0,0,0,0)))
}
</style>
<body>
<div>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Morbi sit amet porttitor massa. Morbi eget tortor congue, aliquet odio a, viverra metus. Ut cursus enim eu felis sollicitudin, vitae eleifend urna lobortis. Mauris elementum erat non facilisis cursus. Fusce sit amet lacus dictum, porta libero sed, euismod tellus. Aenean erat augue, sodales sed gravida ac, imperdiet ac augue. Ut condimentum dictum mauris. Donec tincidunt enim a massa molestie, vel volutpat massa dictum. Donec semper odio vitae adipiscing lacinia.</div>
<img src='http://verysmartbrothas.com/images/random.jpg?9fe95b' />
</body>
</html>