Vertically centering an image within a coloumn : Hi I'm relatively naïve with CSS and am currently re-arranging a template site for my purposes. I've got it all working how I would like apart from I can't vertically centre images in the columns in relation to the size of the other column. Is this possible?

I've tried a few suggestions but no luck yet. Thanks for any help.

    <div class="col-sm-6">
         <img class="img-responsive img-rounded center-block" src="images/test.jpg" alt="">
    </div>
