Following previous post.

In youtube, normal videos in .flv extension have normal quality. But, youtube also have a higher quality video and ready to serve you.If you want to view it online, you just add “&fmt=6” at the end of that file's URL. For example, http://www.youtube.com/watch?v=cr3VZtj2D8U will become http://www.youtube.com/watch?v=cr3VZtj2D8U&fmt=6. If there’s not any change, you replace “&fmt=6” with “&fmt=18”, new address is http://www.youtube.com/watch?v=cr3VZtj2D8U&fmt=18.

When everything is used and has no effect, it means that video was uploaded long time ago. There’s no higher quality video for it.

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