BW(5)

📦
version 7.44.0 · 2 versions
, in nixpkgs unstable

💖 bw(5) — the Black and White image file format 💖

okay so bestie, welcome to bw(5), the manual page for the bw Black and White image file format and its little utility family 🎀 this is from the BRL-CAD docs and honestly it's giving vintage-but-iconic, so let's get into it ✨

🌸 NAME 🌸

bw — the Black and White image file format, plus all the utilities that hang out with it 🫶

✨ FORMAT ✨

okay so a bw file is literally just a sequence of pixels, no cap. each pixel is stored as one unsigned char, which means its intensity runs from 0 (black, the mood) all the way to 255 (white, the glow-up) 💅

the first pixel in a bw file is the lower left corner of the image — yes, bottom-left, that's the main character. then the pixels go left-to-right across each scanline, and the scanlines get written from the bottom to the top of the image. so it's bottom-up energy, periodt 🦋

by convention, bw images are usually square, which is slay because it means you can figure out their dimensions from the file size alone. if they're not square though, often the only thing a program reading the file needs to know is the file width. history left us with two "standard" sizes — 512x512 and the "higher" 1024x1024 👑 and a common practice for other file sizes is to just put the file width in the filename. iykyk.

at some time in the future bw files will probably get self-typing headers so that parameters like their size can be automatically determined by programs. future us is gonna eat, fr fr 🔥

🧚 UTILITIES 🧚

bestie there are so many of these little guys, and they all ate:

  • bw-fb — displays a .bw format image on a framebuffer 🖥️
  • fb-bw — produces a .bw file from a framebuffer image
  • bw-pix — converts a .bw file to a color .pix file 🌈
  • pix-bw — converts a color .pix file to a .bw file
  • bwstat — gives you statistics concerning a .bw file 📊
  • bwhist — displays a histogram on a framebuffer
  • bwmod — a filter to shift and scale pixel intensities ✨
  • bwdiff — yields the difference between two .bw files
  • bwrect — extracts an arbitrary rectangle from a .bw file
  • bwcrop — maps any quadrilateral in a .bw file into any rectangle
  • bwrot — rotates, reverses, or inverts a .bw file 🔄
  • bwscale — scales a .bw file larger or smaller
  • bwfilter — a variety of 3x3 kernel filters for .bw images 🎛️
  • bw3-pix — merges three .bw files into one .pix file
  • pix-bw3 — separates .pix file RGB colors into three .bw files

🍓 FILES 🍓

file.bw

that's it, that's the file 💀

💜 SEE ALSO 💜

brlcad(1), pix(5), and above named programs 🫶 (yes, the whole squad)

🌟 AUTHOR 🌟

BRL-CAD Team 👑

This software is Copyright (c) 1989-2026 by the United States Government as represented by U.S. Army Research Laboratory.

💅 BUG REPORTS 💅

reports of bugs or problems should be submitted via electronic mail to devs@brlcad.org — like, don't suffer in silence bestie, tell them 😭

mwah, that's the whole page 🦋 this was BW(5) from BRL-CAD, and this little rewrite is living in the same 1989-2026 copyright era energy — go forth and slay your pixels ✨💖

📦 where this page comes from