Convert pnm to 4pm Online: pnm24pm
You can use Tom's Editor to easily convert images from
Portable aNy Map .PNM to AtariTools-800 4 players&missiles .4PM.
Tom's Editor is a free, online image manipulation and converter program.
Go to Tom's Editor
PNM images are uncompressed 24 bit RGB images. Can cannot store Alpha channel. PNM images come in 2 types: binary and text. Especially popular on Linux.
AtariTools-800 4 players&missiles is an image format with extension 4PM.