janssen@parc.xerox.com (Bill Janssen) (08/09/90)
In article <990005@hpnmdla.HP.COM> roger@hpnmdla.HP.COM (Roger Petersen) writes:
By the way, don't you want/need a format that has a convenient ASCII
representation (ala bitmap format)?
Why?
One of the problems with "bitmap" format is that it is incredibly bulky.
Pixmap format with 8 or 24 bits per pixel would swell up even more.
The XPM format suggested by Bull is still bulky, but reasonable for pictures
with less than 257 colors in them, but I think it would fail after that (or
at least I don't remember how it handled fatter pixels). But I tend to use
Sun rasterfile in run-length encoded mode for pixmaps. It has reasonable
compression, and is easy to read and write, despite being a binary format.
Bill
--
Bill Janssen janssen@parc.xerox.com (415) 494-4763
Xerox Palo Alto Research Center
3333 Coyote Hill Road, Palo Alto, California 94304jimf@SABER.COM (08/10/90)
|The XPM format suggested by Bull is still bulky, but reasonable for pictures |with less than 257 colors in them, but I think it would fail after that (or |at least I don't remember how it handled fatter pixels). The format defined the length of the pixel in characters. 2 was the only length supported in the sample code, but it's pretty easy to implement longer ones. The loader I wrote for xloadimage can support any length. A text format isn't bad, but it's better to define a very rigid binary format. Xwd isn't too bad except that the loader has to be very complicated to handle all the possible dump formats if it wants to support loading onto different visuals. Something simpler -- such as Sun rasterfile -- is a better choice. Happy hacking, jim frost saber software jimf@saber.com
lehors@oaxaca.inria.fr (Arnaud Le Hors) (08/14/90)
About XPM format, just be patient one more week please. I'm currently
working on the news format and have already written 3 of the 2
functions. The new functions avoid many problems such as predefined
length of pixel in characters.
--
Arnaud LE HORS
BULL Research FRANCE -- Koala Project | Email :
lehors@mirsa.inria.fr
Inria - Sophia Antipolis | Phone : (33) 93 65 77
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