From: lilley@v5.cgu.mcc.ac.uk (Chris Lilley)
Subject: Re: XV problems
Lines: 46
Reply-To: C.C.Lilley@mcc.ac.uk
Organization: Computer Graphics Unit, MCC


In article <1r1iv3$cba@cc.tut.fi>, jk87377@lehtori.cc.tut.fi (Kouhia Juhana) writes:

>Recent discussion about XV's problems were held in some newsgroup.
>Here is some text users of XV might find interesting.

>(I have also minor ideas for 24bit XV, e-mail me for them.)

[Deleted for space; basically complaints that xv is an 8 bit program and that
making several modifications to the RGB sliders is slow because of screen updates.]

In reverse order:

1) Try clicking in the auto-apply box to switch it off. Then make your mods. Then
click on apply. There is no problem as stated; it has already been solved if you
look carefully.

2) Yes XV is an 8 bit program. This is not a bug. You can edit individual pallette
entries or do global colour changes; crop, scale etc. Clearly the program must
save out the *altered* image else all your work would be thrown away. So yes it
saves out 8 bit images - of course!

XV can import 24 bit images and quantises them down to 8 bits. This is a handy
facility, not a bug.

How would you suggest doing colour editing on a 24 bit file? How would you group
'related' colours to edit them together? Only global changes could be done
unless the software were very different and much more complicated.

If you want to do colour editing on a 24 bit image, you need much more powerfull
software - which is readily available commercially.

And lastly, JPEG is a compression algorithm. It can be applied to any image of
arbitrary bit depth. Again, this is not a bug. It is a way of saving disk space
;-)

Later,

--
Chris Lilley
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