max-width: 100%;
max-height: 100%;

<div class="media">
  <img src="http://www.fulltimefba.com/wp-content/uploads/2014/04/bigstock-obstacle-ahead-caution-for-dan-41515888.jpg"/>
</div>

.subcontainer2 .media img {
    height: 100%;
    width: 100%;
    object-fit: contain;
    object-position: top;
}