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There are some ways to make it look at little better. The "enhance buttons" you see on television cleaning up blocky surveillance video.....are not real. Nor will they ever be.

What are you trying to clean up? How bad is it?
 
You can do colour-corrections and procedures of that kind to make your video appear nicer. You can't, however, take a crappy youtube video and make it HD, for example.
 
Get ahold of that software they use on NCIS or Criminal Minds. Just watch the shows and you will see how well it works. It truly is magic. 😉
 
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