[MEncoder-users] Removing strange noise around edges

[Rich Felker]

On Mon, Nov 28, 2005 at 08:53:19PM +0100, Fredrik Eriksson wrote:
> Hello. I've found some ugly noise that I want to remove. Take a look at 
> the sample image: http://winterbird.no-ip.org/sample.png As you can see 
> there is some strange noise around the edges on his red cloths. This 
> noise changes pattern all the time and is very irritating. But the only 
> way I've found to remove it is to overuse the unsharpening and/or 
> denoising filters, resulting in extensive detail loss, and I don't want 
> that...
> 
> Does anyone know a way to remove this ugly noise without destroying the 
> rest of the video? A short sample (copied from the dvd to a mpg file) 
> can be found here: http://winterbird.no-ip.org/sample.mpg

The problem you're seeing is dotcrawl, and there is currently no
filter in mplayer/mencoder to correct for it aside from blurring and
heavy denoising. With telecined content it generally is possible to
correct for this due to some degree of redundancy, but no one has
written a filter for it yet. I'm considering doing so at some point in
the future (since I need it for one of my own projects) but don't hold
your breath..

Rich