Re: transparent GIF pixels

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

Craig Markwardt (craigmnet@cow.physics.wisc.edu) writes:

> David, I think he's talking specifically about GIF transparent pixels.
> I understand that you can reserve one GIF color to be transparent, so
> to speak.  Any pixels with that color are not rendered, so any
> background graphics can show through.  This can be especially useful
> in web programming.  I don't think he's actually trying to render it
> on the screen himself.

I'm not so sure. But I admit "I would like to make them transparent
while the image is in memory." could be open to interpretation.
I thought he wanted to see transparent pixels in IDL. Why else would
he be saving and reading them back?

> Unfortunately, the answer to the question appears to be that there is
> no way to assign transparent GIF pixels in IDL.  There are no options
> to WRITE_GIF that would satisfy this requirement.

Craig, we found something today you and I agree on 100%! It's going
to be a good day, I can feel it. :-)

Cheers,

David

-- 
David Fanning, Ph.D.
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