From Newsgroup: alt.os.linux
The venerable PNM (portable any map) image format that is unique to Unix
is still very much alive and kicking in spite of a plethora of "modern" formats that have been introduced.
I use it ALL the time and therefore one knows that it MUST be damned good.
To process and manipulate PNM images there is the indispensable suite
of utilities and libraries called NetPBM:
https://netpbm.sourceforge.net/
Not only does NetPBM process PNM images but it also contains a host
of general imaging functions that the programmer can utilize such as color space transforms, pixel transforms, etc.
Let us celebrate and give a hearty thanks to NetPBM and its long-time maintainer.
GNU/Linux would be a little less superior without it.
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