[l2h] PNG problems

[taupin]

 Formerly, I was not able to build PNG images due to a bug in pnmtopng
provided in the linux distribution RedHat 5.2

But I got a source (suppoedly recent, from suse) which I finally
succeeded to compile, so that is yields an image, instead of crashing.

The new problem is that the PNG has a gray background, while the GIF is
transparent. Of course I use the same pstoimg routine, just changing the
configuration file (99.2 revision 1.29)

==> Is that grey background with PNG a bug, or a "feature"?
-- 

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  Daniel Taupin, Physique des Solides, Univ. Paris-Sud, 91405 ORSAY
  E-mail= mailto:taupin@lps.u-psud.fr
  Tél: (33)1.69.15.60.79, Fax: (33)1.69.15.60.86, home/fax:
(33)1.60.10.26.44

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