Convert cals to pnm Online: cals2pnm
You can use Tom's Editor to easily convert images from
Continuous Acquisition and Life-cycle Support Type 1 .CALS to Portable aNy Map .PNM.
Tom's Editor is a free, online image manipulation and converter program.
Go to Tom's Editor
Continuous Acquisition and Life-cycle Support Type 1 is an image format with extension CALS.
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.