Convert jbig to pnm Online: jbig2pnm
You can use Tom's Editor to easily convert images from
JBIG image .JBIG to Portable aNy Map .PNM.
Tom's Editor is a free, online image manipulation and converter program.
Go to Tom's Editor
JBIG
JBIG image is an image format with extension JBIG.
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.