Provided by: netpbm_10.97.00-2_amd64 bug


       pnm - Netpbm superformat


       The  PNM  format  is  just an abstraction of the PBM, PGM, and PPM formats.  I.e. the name
       "PNM" refers collectively to PBM, PGM, and PPM.

       The name "PNM" is an acronym derived from "Portable Any Map." This derivation  makes  more
       sense  if  you  consider it in the context of the other Netpbm format names: PBM, PGM, and

       The more general term "Netpbm format" refers to the PNM formats plus PAM.

       PNM is principally used with Netpbm(1).

       Note that besides being names of formats, PBM, PGM, PPM,  and  PNM  are  also  classes  of
       programs.  A PNM program can take PBM, PGM, or PPM input.  That's nothing special -- a PPM
       program can too.  But a PNM program can often produce multiple output formats as well, and
       a  PNM  program can see the difference between PBM, PGM, and PPM input and respond to each
       differently whereas a PPM program sees everything as if it were PPM.   This  is  discussed
       more in the description of the netpbm programs" (1).

       "pnm"  also  appears  in the names of the most general Netpbm library routines(1), some of
       which aren't even related to the PNM format.


       No Internet Media Type (aka MIME type, content type) for PNM has been registered with  the
       IANA, but the value image/x-portable-anymap is conventional.

       Note that there are also conventional Internet Media Types for each of the PNM subformats.
       The recommended practice is to use those  in  preference  to  the  PNM  code  when  it  is
       convenient to do so.


       There  are  no  requirements  on  the name of a PNM file, but the convention is to use the
       suffix "pbm", "pgm", or "ppm", depending on the particular subformat, or "pnm"  if  it  is
       not convenient to distinguish the subformats.


       ppm(1), pgm(1), pbm(1), pam(1), programs that process PNM(1), libnetpbm(1)


       This  manual page was generated by the Netpbm tool 'makeman' from HTML source.  The master
       documentation is at