Fadeeffects
.img-hov-fadein
.img-hov-fadeout
You shoudl apply .img-hov-*classes to a wrapper element of <img>. This could be a <div>, <a>, <figure>, etc. based on your need.
<figure class="img-hov-fadein"> <img src="../assets/img/image.jpg" alt="..."></figure><!-- Clickable --><a class="img-hov-fadein" href="#"> <img src="../assets/img/image.jpg" alt="..."></a>Zoomeffects
.img-hov-zoomin
.img-hov-zoomout
.img-hov-stretchin
.img-hov-stretchout
Slideeffects
.img-hov-slideleft
.img-hov-slideright
.img-hov-slideup
.img-hov-slidedown
Rotateeffects
.img-hov-rotateleft
.img-hov-rotateright