Convert gd2 to pnm Online: gd22pnm

You can use Tom's Editor to easily convert images from
GD Library 2 Image .GD2 to Portable aNy Map .PNM.
Tom's Editor is a free, online image manipulation and converter program.

Go to Tom's Editor

GD2

GD Library 2 Image is an image format with extension GD2.

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.