1The PNM Format(5) File Formats Manual The PNM Format(5)
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6 pnm - Netpbm superformat
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10 The PNM format is just an abstraction of the PBM, PGM, and PPM formats.
11 I.e. the name "PNM" refers collectively to PBM, PGM, and PPM.
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13 The name "PNM" is an acronym derived from "Portable Any Map." This
14 derivation makes more sense if you consider it in the context of the
15 other Netpbm format names: PBM, PGM, and PPM.
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17 The more general term "Netpbm format" refers to the PNM formats plus
18 PAM.
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20 PNM is principally used with Netpbm(1).
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22 Note that besides being names of formats, PBM, PGM, PPM, and PNM are
23 also classes of programs. A PNM program can take PBM, PGM, or PPM
24 input. That's nothing special -- a PPM program can too. But a PNM
25 program can often produce multiple output formats as well, and a PNM
26 program can see the difference between PBM, PGM, and PPM input and
27 respond to each differently whereas a PPM program sees everything as if
28 it were PPM. This is discussed more in the description of the netpbm
29 programs" (1).
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31 "pnm" also appears in the names of the most general Netpbm library rou‐
32 tines(1), some of which aren't even related to the PNM format.
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36 No Internet Media Type (aka MIME type, content type) for PNM has been
37 registered with the IANA, but the value image/x-portable-anymap is con‐
38 ventional.
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40 Note that there are also conventional Internet Media Types for each of
41 the PNM subformats. The recommended practice is to use those in pref‐
42 erence to the PNM code when it is convenient to do so.
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46 There are no requirements on the name of a PNM file, but the convention
47 is to use the suffix "pbm", "pgm", or "ppm", depending on the particu‐
48 lar subformat, or "pnm" if it is not convenient to distinguish the sub‐
49 formats.
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54 ppm(1), pgm(1), pbm(1), pam(1), programs that process PNM(1), lib‐
55 netpbm(1)
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58 This manual page was generated by the Netpbm tool 'makeman' from HTML
59 source. The master documentation is at
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61 http://netpbm.sourceforge.net/doc/pnm.html
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63netpbm documentation 27 November 2013 The PNM Format(5)