Dialogic 6.2 - Manual (Page 418)

G3 Conversion Utility (g3cvt)
November 2009 418
For example:
g3cvt MMR fax.mmr MH fax.mh
converts a fax file from MMR format to MH format.
-h
Causes g3cvt to copy the first 128 bytes of the input file to
the output file, with no conversion.
-f
Specifies fine resolution input. Used with MR or PCX
output only.
MR output—The program represents the data slightly
differently and more efficiently when it knows the input
is in fine resolution.
PCX output—Since PCX format is always in fine
resolution, the program must know whether the input file
is in fine or normal resolution. If the input is in normal
resolution, the program doubles each line in the output
file.
A PCX input file automatically activates the -f option.