Convert bum to pnm Online: bum2pnm

You can use Tom's Editor to easily convert images from
Poser Bump Map .BUM to Portable aNy Map .PNM.
Tom's Editor is a free, online image manipulation and converter program.

Go to Tom's Editor

BUM

Poser Bump Map is an image format with extension BUM.

PNM

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.