\
.\" This man page was generated by the Netpbm tool 'makeman' from HTML source.
.\" Do not hand-hack it!  If you have bug fixes or improvements, please find
.\" the corresponding HTML page on the Netpbm website, generate a patch
.\" against that, and send it to the Netpbm maintainer.
.TH "Pbmtog3 User Manual" 0 "20 April 2017" "netpbm documentation"

.SH NAME
pbmtog3 - convert a PBM image into a Group 3 MH fax file

.UN synopsis
.SH SYNOPSIS

\fBpbmtog3\fP
[\fB-reversebits\fP]
[\fB-nofixedwidth\fP]
[\fB-align8\fP|\fB-align16\fP]
[\fIpbmfile\fP]

.UN description
.SH DESCRIPTION
.PP
This program is part of
.BR "Netpbm" (1)\c
\&.
.PP
\fBpbmtog3\fP reads a PBM image as input and produces a Group 3 MH fax
file as output.
.PP
You can also generate a TIFF file that uses the same encoding
inside, with \fBpamtotiff\fP.
.PP
There is no program in Netpbm that generates other fax formats,
such as MR and MMR, but \fBpamtotiff\fP can generate TIFF files that
use those encodings.

.UN options
.SH OPTIONS
.PP
In addition to the options common to all programs based on libnetpbm
(most notably \fB-quiet\fP, see 
.UR index.html#commonoptions
 Common Options
.UE
\&), \fBpbmtog3\fP recognizes the following
command line options:


.TP
\fB-reversebits\fP
This option causes the output to have the bits in every byte
reversed so the least significant bit becomes the most significant bit.
Some fax modems expect bits in reverse order, and this compensates for
that. If you get a whole bunch of "bad code word" messages when you try
to read the G3 file (e.g. with \fBg3topbm\fP), try using this option.
Note that the output is not G3 when you use this option.

.TP
\fB-nofixedwidth\fP
Most fax machines expect the image to be 1728 columns wide, so
\fBpbmtog3\fP cuts the output to this width by default.  If you want to
keep the width of the original image, use this option.
.sp
This option was new in Netpbm 10.6 (July 2002).  Before that,
\fBpbmtog3\fP always kept the width of the original image.

.TP
\fB-align8\fP
.TP
\fB-align16\fP
These options say to align output rows to 8-bit or 16-bit boundaries,
respectively, by adding padding bits in front of EOL codes
.sp
Without these options, \fBpbmtog3\fP adds no padding and rows may begin
and ends anywhere within a byte.
.sp
You cannot specify both.
.sp
These options were new in Netpbm 10.79 (June 2017).     



.UN seealso
.SH SEE ALSO
.BR "g3topbm" (1)\c
\&,
.BR "pamtotiff" (1)\c
\&,
.BR "pbm" (1)\c
\&,
.BR "fax formats" (1)\c
\&

.UN history
.SH HISTORY
.PP
Before Netpbm 10.79 (June 2017), there was a different program by the same
name in Netpbm, which was written by by Paul Haeberli
<\fIpaul@manray.sgi.com\fP> in 1989
and then modified extensively by others.
.PP
Akira Urushibata <afu@wta.att.ne.jp> wrote the current version, with
an entirely different algorithm, in April 2017 and contributed his work to the
public domain.
.PP
The current program is backward compatible with the pre-10.79 version.
.SH DOCUMENT SOURCE
This manual page was generated by the Netpbm tool 'makeman' from HTML
source.  The master documentation is at
.IP
.B http://netpbm.sourceforge.net/doc/pbmtog3.html
.PP