From: John Russ <drjohnruss@AOL.com>
Subject: Re: convolution filter
Date: 19 Jul 2000 00:00:00 GMT
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Gordy wrote:

> a color, you would have to apply that to each channel
>
> > When they speak about Pixel value in a convolution filter what does that
> > mean exactly ?
> >
> > To apply a linear filter,
> > BUT WHAT IS Pixel ???
> > A Color ? A Lightness ?

Actually, applying convolutions to the RGB channels in an image is usually
wrong. For most purposes processing the image in an HSI space and modifying
only the I channel, leaving the color information alone, produces the best
results