Convert icn to pnm Online: icn2pnm
You can use Tom's Editor to easily convert images from
ICE CIN .ICN to Portable aNy Map .PNM.
Tom's Editor is a free, online image manipulation and converter program.
Go to Tom's Editor
ICE CIN is an image format with extension ICN.
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.