Displaying video previews from various providers

My use case is kinda basic. According to the URL a user inputs, I want to have the good player displayed, that varies according to the input of course.

For ins开发者_如何转开发tance, inputting http://www.youtube.com/watch?v=rv5OwTiBEiQ would display the preview of the Youtube player. The same goes with Dailymotion, Yahoo!, Vimeo, Justin.tv, Myspace...

Do you know is any Javascript plugin does this ? Ideally, it'd be based on Prototype.

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In the Youtube case, all you have to do is get the video id of the url and put this in the follow URL:

http://img.youtube.com/vi/{video-id}/1.jpg

Then you have the link to the youtube preview image!