SOURCE

<img class="p1-cai1-ani " src="http://www.ivgis.com/girl.jpg" />

.p1-cai1-ani {
	  position: absolute;
	  height: 300px;
	  width: 300px;
	  -webkit-animation: tra3Clip-ani 2s linear 2s both infinite;
	  animation: tra3Clip-ani 2s linear 2s both infinite;
	}
	
	@keyframes tra3Clip-ani {
	  from {
	    opacity: 1;
	    -webkit-clip-path: polygon(200% 0%, 200% 0%, 0% 200%, 0% 200%);
	    clip-path: polygon(200% 0%, 200% 0%, 0% 200%, 0% 200%);
	  }
	  to {
	    opacity: 1;
	    -webkit-clip-path: polygon(200% 0%, 0% 0%, 0% 0%, 0% 200%);
	    clip-path: polygon(200% 0%, 0% 0%, 0% 0%, 0% 200%);
	  }
	}
	
	@-webkit-keyframes tra3Clip-ani {
	  from {
	    opacity: 1;
	    -webkit-clip-path: polygon(200% 0%, 200% 0%, 0% 200%, 0% 200%);
	    clip-path: polygon(200% 0%, 200% 0%, 0% 200%, 0% 200%);
	  }
	  to {
	    opacity: 1;
	    -webkit-clip-path: polygon(200% 0%, 0% 0%, 0% 0%, 0% 200%);
	    clip-path: polygon(200% 0%, 0% 0%, 0% 0%, 0% 200%);
	  }
	}