jQuery make nested element (img / video) cover the container area with debounced resize listener

gistfile1.txt

$(function () {
  var resizeTimer;
  $(window).resize(function() {
    clearTimeout(resizeTimer);
    resizeTimer = setTimeout(onResize, 50);
  });
  onResize();

  function onResize() {
    var $container = $("#container"),
      $content   = $("#content"),
      containerRatio = $container.width() / $container.height(),
      contentRatio = $content.width() / $content.height()

      if (containerRatio < contentRatio) {
        $content.css({
          marginLeft: -($content.height() * contentRatio - $container.width()) / 2,
          marginTop: "auto",
          height: "100%",
          width: "auto"
        });
      } else {
        $content.css({
          marginLeft: "auto",
          marginTop: -($content.width() / contentRatio - $container.height()) / 2,
          height: "auto",
          width: "100%"
        });
      }
    });
  }
});