This submodule keeps the PNM encode/decode capabilities
of the Image module.
PNM is a common image storage format on unix systems,
and is a very simple format.
This format doesn't use any color palette.
The format is divided into seven subformats;
P1(PBM) - ascii bitmap (only two colors)
P2(PGM) - ascii greymap (only grey levels)
P3(PPM) - ascii truecolor
P4(PBM) - binary bitmap
P5(PGM) - binary greymap
P6(PPM) - binary truecolor
Simple encoding:
Image.PNM.encode,
Image.PNM.encode_binary,
Image.PNM.encode_ascii
Simple decoding:
Image.PNM.decode
Advanced encoding:
Image.PNM.encode_P1,
Image.PNM.encode_P2,
Image.PNM.encode_P3,
Image.PNM.encode_P4,
Image.PNM.encode_P5,
Image.PNM.encode_P6
Image.PNG.encode()