JQuery to make images cover their containing elements (cropped)

cover-element.js

$(document).ready(function () {
    // Find thumbnail containers
    $('.thumbContainer').each(function () {
        // Get current thumbnail container
        var thumb = $(this);
        // Get current thumbnail image
        var img = thumb.children('img');
        // Calculate image ratio
        var ratio = img.innerWidth() / img.innerHeight();
        var newW, newH;
        // Calculate new width & height
        if (ratio >= 1) {
            newH = thumb.outerHeight();
            newW = newH * ratio;
        } else {
            newW = thumb.outerWidth();
            newH = newW / ratio;
        }
        // Apply new width & height
        img.width(newW);
        img.height(newH);
        // Calculate and apply offsets        
        img.css('top', (thumb.innerHeight() - newH) / 2);
        img.css('left', (thumb.innerWidth() - newW) / 2);
    });
});

styles.css

.parent {
  position: relative;
  overflow: hidden;
}

.parent img {
  position: absolute;
}