An application I\'m working on needs to get HQ YouTube thumbnails given a URL. Using this answer, I tried using the maxresdefault.jpg to get the maximum resolut
maxresdefault.jpg
Update 2019 ::
https://i.ytimg.com/vi//hqdefault.jpg
Seems to return highest possible image....
1.jpg, 2.jpg, 3.jpg return previews through the length of the clip which are handy also ;)