I have this code and works correctly but I'm wondering if it can be optimized to not repeat the formats in capitalize & lowercase (?:mp4|MP4|webm|WEBM|mov|MOV|ogg|OGG))
$post[message] = preg_replace('/<a href="(.+?\.(?:mp4|MP4|webm|WEBM|mov|MOV|ogg|OGG))" target="_blank">(.+?)<\/a>/', '<video controls="" src="$1" style="max-width: 640px; max-height: 360px;outline:none;" loop>VIDEO HTML5</video>', $post[message]);