[mpeg2] Re: deinterlacer

[Rob Morris <rmorris@cdlsystems.com>]

The problem you are seeing is know as feathering, and it is an artifact that
occurs with the deinterlacing an interlaced signal on a progressive scan
monitor. Two types of deinterlacing are often used, one is call 'bob' and
the other 'weave'. Since an NTSC or PAL signal consists of two interlaced
fields we have two choices. We can display the odd fields on the odd lines,
then the even fields on the even lines. This is known as weave
deinterlacing, and is the phenomena shown in your screenshot. With 'bob'
deinterlacing, each line in each field is displayed double height - since a
field is only 320 lines (in NTSC). The feathering does not occur in this
situation but you get a slight bobbing of the video. Usually the selection
between bob and weave can be controlled as an attribute of the display
software. (It may be called something like interlaced as well.) I don't
think that this is not an artifact of the Kfir encoding, because I see it
when directly observing an NTSC signal on an computer monitor.

-----Original Message-----
From: mpeg2-bounce@linuxtv.org [mailto:mpeg2-bounce@linuxtv.org]On
Behalf Of Torsten Howard
Sent: Wednesday, July 11, 2001 3:05 PM
To: mpeg2@linuxtv.org
Subject: [mpeg2] deinterlacer


Hello,

I am recording throught the mpeg2 kfir card a composite
video signal from a VHS tape.

The digital quality appears about that of the video signal, except
when there is motion.  The I get some very annoying interlacing
lines around the moving objects.

Amazingly, I have found a replica of the problem here:
http://deinterlace.sourceforge.net/screenshots/index.htm

They seem to have the solution to the problem - does anyone
know how I can stop the interlacing around moving objects with
the kfir card?  How do i deinterlace the signal?

Their solution seems to only work with analog pictures on a
projector, but I haven't read enough to figure out exactly what they
are doing - except that their software is currently only windows GPL,
I'll rip the source and port if I absolutely have to, but I would like to
know if anyone has found a solution thus far to this problem.

Thanks,
Torsten