r.out.ppm3(1)

📦
version 8.4.2 · 8 versions
, in fedora 44

💖 r.out.ppm3 — the GRASS GIS bestie that turns three rasters into one cute PPM 💖

okay so bestie, this is r.out.ppm3(1) from the GRASS GIS User's Manual, and it is literally the glow-up your raster data deserves. it takes three raster layers (R, G, B — you know the vibe) and smooshes them into a single PPM image file. periodt. ✨

🌈 NAME 🌈

r.out.ppm3 — converts 3 GRASS raster layers (R,G,B) to a PPM image file. it's giving color theory. it's giving export. it's giving main character. 🎀

🏷️ KEYWORDS 🏷️

raster, export, output

iykyk 💅

✨ SYNOPSIS ✨

r.out.ppm3
r.out.ppm3 --help
r.out.ppm3 [-c] red=string green=string blue=string output=string
[--help]  [--verbose]  [--quiet]  [--ui]

🚩 Flags 🚩

  • -c — add comments to describe the region. so the image is self-aware, love that for it 🫶
  • --help — print usage summary. your emotional support documentation 💖
  • --verbose — verbose module output. it will tell you everything 🗣️
  • --quiet — quiet module output. it's giving silent treatment 🙈
  • --ui — force launching GUI dialog. for when you want the clicky-clicky experience 🖱️✨

🎀 Parameters 🎀

  • red=string [required] — name of raster map to be used for <red>. the rosy one 🌹
  • green=string [required] — name of raster map to be used for <green>. the fresh one 🌿
  • blue=string [required] — name of raster map to be used for <blue>. the dreamy one 🦋
  • output=string [required] — name for new PPM file. (use '-' for stdout). yes, a literal dash means "just yeet it to stdout," iconic 🎯

💜 DESCRIPTION 💜

r.out.ppm3 converts 3 GRASS raster layers (R,G,B) to a PPM image file, using the current region. no cap.

this program converts a GRASS raster map to a PPM image file using the the current region settings. (and yes, the original says "the the" — we are leaving that exactly as it is, it's part of the lore now 😭💀)

to get the full area and resolutin of the raster map, run:

g.region raster=[mapname]

before running r.out.ppm3. do it in that order bestie, don't skip the warm-up 🧚

📝 NOTES 📝

one pixel is written for each cell value, so if ew_res and ns_res differ, the aspect ratio of the resulting image will be off. so like… the image might look a lil stretched. that's not a bug, that's just the math being math 😭🫠

lowkey important: if your ew_res and ns_res aren't matching, your output is gonna be squished or smeared. set your region thoughtfully before you export. ⭐

👀 SEE ALSO 👀

r.out.ppm, r.in.gdal, d.rgb

go read those next, they're all part of the same friend group 💞

👑 AUTHOR 👑

Glynn Clements

Based upon r.out.ppm and d.rgb. building on the classics, we love to see it 🔥

🧾 SOURCE CODE 🧾

Available at: r.out.ppm3 source code (history)

Accessed: Saturday Jan 17 05:40:53 2026

Main index | Raster index | Topics index | Keywords index | Graphical index | Full index

okay that's the whole page bestie!! 💖✨ this was all brought to you by the © 2003-2025 GRASS Development Team, GRASS GIS 8.4.2 Reference Manual — and this lil doc lives in GRASS 8.4.2 as r.out.ppm3(1). mwah, go export something gorgeous 🎀🌈💅

📦 where this page comes from