Video Thumbnails
https://img.youtube.com/vi/<insert-youtube-video-id-here>/default.jpg
https://img.youtube.com/vi/<insert-youtube-video-id-here>/hqdefault.jpg
https://img.youtube.com/vi/<insert-youtube-video-id-here>/mqdefault.jpg
https://img.youtube.com/vi/<insert-youtube-video-id-here>/sddefault.jpg
https://img.youtube.com/vi/<insert-youtube-video-id-here>/maxresdefault.jpg
http://vimeo.com/api/v2/video/[video-ID].php
https://graph.facebook.com/[video-ID]/picture