.pic{position:relative;}
.glass{display:block;}
.glass i{display: block;width: 248px;height: 187px;position: absolute;top:0px;left: 365px;-webkit-transform: skewX(-49deg);
background: -webkit-linear-gradient(left,rgba(255, 255, 255, 0),rgba(255, 255, 255, 0.7),rgba(255, 255, 255, 0));-webkit-transition: 0s;}
a:hover .glass i{top:;left:-365px;-webkit-transition:0.5s;}
<a href="" class="pic">
<div class="glass">
<img src="http://rs.moxian.com/sz/upload/2013/20130307/5546/201303070430464365_small.jpg" />
<i></i>
</div>
</a>