[MPlayer-dev-eng] watermark removal

[D Richard Felker III]

On Sun, Nov 03, 2002 at 11:08:51PM +0100, Jindrich Makovicka wrote:
> Michael Niedermayer wrote:
> 
> >Hi
> >
> >On Sunday 03 November 2002 22:50, D Richard Felker III wrote:
> > 
> >
> >>I'm working on a watermark removal filter to get rid of those pesky
> >>semi-transparent watermarks that appear on some movies (especially
> >>stuff recorded from tv and/or released by lame encoding groups).
> >>However, I can't seem to figure out quite how to make it work. My
> >>first idea was based on capturing an otherwise all-black frame from
> >>the movie with just the watermark showing, then having the filter use
> >>that for removing the watermark, but things seem to be a bit more
> >>complicated. I can't seem to figure out how the watermarks are
> >>typically applied -- it doesn't seem to be simple addition or
> >>averaging, so maybe it's some sort of weighted average. Any ideas? The
> >>movie I'm experimented on was apparently watermarked with some stupid
> >>virtualdub filter, so perhaps someone knows how that functions...
> >>   
> >>
> >RTFS of virtualdub & filters ;), no i dunno how its added but imho the 
> >problem might be that mpeg compression causes errors and so even if the 
> >removial equation is correct it cant be removed ...
> >
> here's a logo removal filter for VD, with source:
> 
> http://shelob.mordor.net/dgraft/delogo/delogo.html

Wow, looks nice. It's really messy C++ source, so it'd take a while to
port to mplayer, but I might look into it. I had in mind something
much simpler, but a smarter tool like that would be great!

Rich