PBMTOG3(1)

💖 Pbmtog3 User Manual 💖

okay bestie, welcome to the Pbmtog3 page from the General Commands Manual section of the Netpbm docs ✨ no cap, this one's a lil niche but it's lowkey iconic.

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✨ NAME ✨

pbmtog3 — convert a PBM image into a Group 3 MH fax file 💅

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🎀 SYNOPSIS 🎀

pbmtog3 [-reversebits] [-nofixedwidth] [-align8|-align16] [pbmfile]

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🦋 DESCRIPTION 🦋

So this program is part of Netpbm(1), fr fr. 🌈

pbmtog3 reads a PBM image as input and produces a Group 3 MH fax file as output. That's the whole vibe. In, out, slay. 💖

You can also generate a TIFF file that uses the same encoding inside, with pamtotiff. 👑

And jsyk — there is no program in Netpbm that generates other fax formats, such as MR and MMR, but pamtotiff can generate TIFF files that use those encodings. So if you're looking for those, it's giving "go ask pamtotiff instead." 🙈

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💅 OPTIONS 💅

On top of the options common to all programs based on libnetpbm (most notably -quiet, see Common Options), pbmtog3 recognizes the following command line options:

• -reversebits — this one flips the bits in every byte of the output, so the least significant bit becomes the most significant bit. Some fax modems expect bits in reverse order, and this compensates for that. 🌀 So if you're getting a whole bunch of "bad code word" messages when you try to read the G3 file (e.g. with g3topbm), try using this option. Note that the output is not G3 when you use this option. 🚨 like, do not come for me, that's just how it is.
• -nofixedwidth — most fax machines expect the image to be 1728 columns wide, so pbmtog3 cuts the output to this width by default. If you want to keep the width of the original image, use this option. 🫶

This option was new in Netpbm 10.6 (July 2002). Before that, pbmtog3 always kept the width of the original image. 🕰️

• -align8
• -align16 — these options say to align output rows to 8-bit or 16-bit boundaries, respectively, by adding padding bits in front of EOL codes. 📏

Without these options, pbmtog3 adds no padding and rows may begin and ends anywhere within a byte. (yes, the original says "begins and ends," we're keeping that energy, it's iconic in its own way 💀)

You cannot specify both. pick a lane bestie, not both. 🙅‍♀️

These options were new in Netpbm 10.79 (June 2017). ⭐

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👀 SEE ALSO 👀

g3topbm(1), pamtotiff(1), pbm(1), fax formats(1)

iykyk, go read those next. 💜

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📜 HISTORY 📜

Before Netpbm 10.79 (June 2017), there was a different program by the same name in Netpbm, which was written by by Paul Haeberli <paul@manray.sgi.com> in 1989 and then modified extensively by others. the lore is real. 😭

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. 🎀 legend behavior.

The current program is backward compatible with the pre-10.79 version. so nothing broke, we love to see it. ✨

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📄 DOCUMENT SOURCE 📄

This manual page was generated by the Netpbm tool 'makeman' from HTML source. The master documentation is at

http://netpbm.sourceforge.net/doc/pbmtog3.html

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okay and that's the whole page bestie, thank you for coming to my TED talk 🫶 this lil cutie is brought to you by the netpbm documentation, dated 20 April 2017, and it lives under the Pbmtog3 User Manual(1) header. mwah 💋 so glad we read this together, go convert some faxes 💖✨🎀