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From: "Robbie Janssen" <r.j.m.janssen@student.tue.nl>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Image filters,Edge detectors
Date: Tue, 6 May 2008 09:46:03 +0000 (UTC)
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I still don't get the same result Yumnam. I am using Matlab 
release 7.5.0(R2007b), it should be a strange thing but 
maybe there's where the error is? I've posted a picture at 
http://www.student.tue.nl/t/r.j.m.janssen/FILTERS.jpg 

The kernel (or mask) is defined as [0 -1; 1 0] 

Can you maybe take a look at it and explain why there's 
still a difference?

Regards,

Robbie

Yumnam Kirani Singh <kirani.singh@gmail.com> wrote in 
message 
<30971887.1199861291430.JavaMail.jakarta@nitrogen.mathforum.
org>...
> Sorry, I have made a mistake in the explanation of 
filter2 and conv2. The two are equivalent under the 
following cases.
> >>xf=filter2(fliplr(mask),x); % using as conv2
> >>xc=conv2(x,mask, 'same');
> then xc and xf are the same.
> In the other way,
> >>xc=conv2(x,fliplr(mask), 'same'); % using as filter2
> >>xf=filter2(mask,x);
> here also, xc and xf will give the same result.