wordpress php change oembed code for videos - php

Question

As most people know, wordpress uses oembed to fetch the embed code for videos when adding a youtube video to a post. For example, pasting:
https://www.youtube.com/watch?v=pATcvr3zAhg
Would output this in the html:
<iframe width="420" height="315" src="https://www.youtube.com/embed/pATcvr3zAhg" frameborder="0" allowfullscreen></iframe>
I want to change this markup so it uses fancybox and an image, so my markup should look like this:
<a class="fancybox.iframe various" href="VIDEO SOURCE"><img src="IMAGE HERE"></a>
I was using this code which originally replaced the video with an image and when clicked, changed to the video - however, I want to modify this code now so that it outputs the markup above.
add_filter( 'oembed_dataparse', function($str, $data, $url) {
if ( ($yt = $data->provider_name == 'YouTube') || ($vm = $data->provider_name == 'Vimeo') )
{
if($yt) $html = str_replace('feature=oembed', 'feature=oembed&autoplay=1', $str);
else $html = str_replace('" width=', '?autoplay=1" width=', $str);
$html = htmlentities($html, ENT_QUOTES);
$img = $data->thumbnail_url;
$title = esc_attr($data->title);
return '<img src="'. $img . '" onclick="this.outerHTML=\'' . $html . '\'" title="' . $title . '">';
}
return $str;
}, 10, 3);