Can someone tell me how to remove logos from movies?
A guide will be helpful.

I dont have a guide, but on virtualdub.org you can get various
logo-away filters....Hope this helps you..

when i filter it does the size of the movie file increase?

Probably yes, because these filters use all sorts of projection/blurring/sharping/etc/etc. filters. For example, file size also
increases when you use sharpning filter while authoring your kvcd.

Of course, the filesize of your kvcd will not be affected by the size of your avi file. It's the length of the movie and the aspect ratio that counts..!

there is logo removal discussion at this post http://www.kvcd.net/forum/viewtopic.php?t=7592

There are several options to remove logos.

Virtualdub has at least three logo removal tools: DeLogo, XLogo and logoaway.

All of these tools can be imported into Avisynth to remove the logos but all will do a RGB converson before removing the logo.

In Avisynth there are three options: Xlogo, NoLogo and DeKafka.

XLogo is a port of VDub's filter and is very good. It is effective on both opaque and transparent logos. It requires some fiddling to get it to work but it shouldn't be that hard. Here's a thread that discusses using it:
http://www.kvcd.net/forum/viewtopic....ighlight=xlogo

NoLogo is my filter that is designed to work on transparent logos. It will produce simular results as Xlogo but with less fiddling. NoLogo is part of the LogoTools DLL that includes several filters. Here's the thread about that:

http://www.kvcd.net/forum/viewtopic....ghlight=nologo

Dekafka is really an Avisynth 2.5 script function. You can find it on the Avisynth site. It works on opaque logos with OK results. It too does an RGB conversion. Another option for this kind of filter is to use my LogoTools version with can be used with either Avisynth 2.x or 2.5 and doesn't do an RGB conversion. I've included my DeKafka tool in the LogoTools download here: http://www.geocities.com/mrtibsvideo/Logotools.html

Edit: I am writing a logo remover for opaque logos but I need examples. It you want to send me a video sample, contact me via private message.

You can use avisynth's Overlay to remove logos, but it's easier for solid blocks...
You can put a black square wherever you want e.g.

black=BlankClip(video, width=56,height=24)
video=video.overlay(black, x=561,y=56,mode="blend",opacity=1)