DOCBOOK-APPS: Images in DocBook documents

Hi folks,

Since I need to generate PDF and PS output
from my DocBook docs, and I accomplish that
by using passiveTEX, I have to keep the
same images twice: one in PNG format and another
one in PS format.

Well, is there a way to produce PS output
without having to keep the same image twice
(in PNG as well as in PS format)?

Thanks,

-- 
Giuseppe Greco
Strada Regina 40
6928 Manno (TI)
Switzerland

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