PNMTODDIF(1)

💖 pnmtoddif — the glow-up your PNM pic deserves 💖

okay bestie, so this is a page from the Pnmtoddif User Manual, section 1 (General Commands Manual), and it's literally about turning your Netpbm pics into DDIF files. no cap. let's get into it ✨

---

🦋 NAME 🦋

pnmtoddif — converts a PNM image into DDIF format. that's it, that's the whole job, and she does it flawlessly 💅

---

🌸 SYNOPSIS 🌸

pnmtoddif [-resolution x y] [pnmfile [ddiffile]]

---

🎀 DESCRIPTION 🎀

so first things first: this program is part of Netpbm(1) 👑 you know the family.

pnmtoddif takes a PNM image and converts it into a DDIF image file. simple as that, she just does it.

and here's the breakdown of what she writes, depending on what you hand her:

• PBM format data (bitmap) → she writes a 1 bit DDIF
• PGM format data (grayscale) → she writes an 8 bit grayscale DDIF
• PPM format data (color) → she writes an 8,8,8 bit color DDIF

any DDIF image file she writes is uncompressed, just so you know. and the data plane organization is interleaved by pixel. periodt ✨

okay now here's the part that's lowkey important 🫶 DDIF images carry more than just the number of pixels in the width and height dimension — they also carry info about the size the image should have, like the physical space that a pixel occupies. and Netpbm images? they do NOT carry that info, bestie. so you have to supply it yourself externally. not optional, it's just how it is.

the default of 78 dpi has the beneficial property of not causing a resize on most Digital Equipment Corporation color monitors. so like, it just fits. iconic behavior honestly 💜

---

✨ OPTIONS ✨

on top of the options common to all programs based on libnetpbm (most notably -quiet, see Common Options), pnmtoddif recognizes this one command line option:

• -resolution x y — the horizontal and vertical resolution of the output image, in dots per inch. default is 78 dpi. 🌈

---

🧚 ARGUMENTS 🧚

• pnmfile — the filename for the image file in pnm format. default is to read from Standard Input.
• ddiffile — the filename for the image file to be created in DDIF format. by default, pnmtoddif writes to Standard Output.

---

👑 SEE ALSO 👑

pnm(1)

---

💜 AUTHOR 💜

Burkhard Neidecker-Lutz, Digital Equipment Corporation, CEC Karlsruhe neideck@nestvx.enet.dec.com

---

📜 DOCUMENT SOURCE 📜

this manual page was generated by the Netpbm tool makeman from HTML source. the master documentation lives at:

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

---

fr fr take a moment to appreciate that the master docs are right there if you ever need them 🙈

---

and that's the whole thing bestie 🍓 this was netpbm documentation, dated 2003, from the Pnmtoddif User Manual, section 1. slay, go convert something 💖✨🎀