Convert pgx to pnm Online: pgx2pnm
You can use Tom's Editor to easily convert images from
PGX of JPEG 2000 .PGX to Portable aNy Map .PNM.
Tom's Editor is a free, online image manipulation and converter program.
Go to Tom's Editor
PGX of JPEG 2000 is an image format with extension PGX.
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.