Based on Andi Wilkinson's answer (the second one), I improved a little, make sure the center of the image is shown (like the accepted answer did):
HTML:
<div class="crop">
<img src="img.png">
</div>
CSS:
.crop{
height: 150px;
width: 200px;
overflow: hidden;
}
.crop img{
width: 100%;
height: auto;
position: relative;
top: 50%;
-webkit-transform: translateY(-50%); /* Ch <36, Saf 5.1+, iOS < 9.2, An =<4.4.4 */
-ms-transform: translateY(-50%); /* IE 9 */
transform: translateY(-50%); /* IE 10, Fx 16+, Op 12.1+ */
}