.gazou {
overflow: hidden;
width: 200px;
height: 200px;
position: relative;
}
.gazou img {
position: absolute;
top: 50%;
left: 50%;
-webkit-transform: translate(-50%, -50%);
-ms-transform: translate(-50%, -50%);
transform: translate(-50%, -50%);
width: 100%;
height: auto;
}