Visual Composer - YT Videos with auto loop

functions.php

<?php
add_action('wp_footer', 'pp_convert_youtube' );
function pp_convert_youtube() {
?>
	<script>
	jQuery(document).ready(function( $ ) {
		$(".wpb_video_wrapper iframe").each( function() {
			var old_src = $(this).attr("src");

			/* get the youtube id from the src attribute */
			var yt_id   = old_src.match("embed/(.*)?feature=oembed");
			yt_id       = yt_id[1].slice(0,-1);

			/* now add the missing parameters and update src attribute */
			var new_src = old_src + '&loop=1&playlist=' + yt_id;

			$(this).attr("src", new_src);
		});
	});
	</script>

<?php
}