Linux Commands Examples

A great documentation place for Linux commands


convert a Group 3 fax file into a portable bitmap

see also : pbmtog3


g3topbm [-kludge] [-reversebits] [-stretch] [g3file]

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Reads a Group 3 fax file as input. Produces a portable bitmap as output.



Tells g3topbm to ignore the first few lines of the file; sometimes fax files have some junk at the beginning.


Tells g3topbm to interpret bits least-significant first, instead of the default most-significant first. Apparently some fax modems do it one way and others do it the other way. If you get a whole bunch of "bad code word" messages, try using this flag.


Tells g3topbm to stretch the image vertically by duplicating each row. This is for the low-quality transmission mode.

All flags can be abbreviated to their shortest unique prefix.


The standard for Group 3 fax is defined in CCITT Recommendation T.4.



see also

pbmtog3 , pbm


Copyright (C) 1989 by Paul Haeberli <paul[:at:]manray.sgi[:dot:]com>.

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