Re: RGB image to 8 bit ??

[davidf(at)dfanning.com (David Fanning)]

Liam Gumley (Liam.Gumley@ssec.wisc.edu) writes:

> That said, I also think a 24-bit capable version of XInteranimate would
> be useful.

You know, as soon as I sent that post yesterday I started worrying
that I may had gotten it wrong. I remember wanting to display
24-bit images in XInteranimate, and I remember looking at the 
code, and I remember that whatever I did was very simple, but
I couldn't q-u-i-t-e remember what I actually did. So I went
back this morning and looked at the code. And it turns out
I did *nothing*! 

That's right. XInterAnimate is *already* 24-bit image
compliant. [Sorry, RSI. :-(]

Actually, it is the fact that XInterAnimate uses the
Device Copy technique of transferring each image frame
from its pixmaps to the display window that makes it
so. This technique doesn't care *what* is in the window,
it just transfers the "bits", if you like.

So, you use XInterAnimate with 24-bit images, all you have
to do is load them properly:

   XInterAnimate, /ShowLoad, Set=[512, 512, 15]
   For J=0, 14 DO BEGIN
      TV, image24[j], True=1
      XInterAnimate, Frame=j, Window=!D.Window
   EndFor
   XInterAnimate

It is true that you can't use the IMAGE keyword, and that
is a shame, but this may be the preferred solution anyway,
since you don't have to do any COLOR_QUANing at all to use
it.

Cheers,

David

-- 
David Fanning, Ph.D.
Fanning Software Consulting
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