Pnmtopnm User Manual(1) General Commands Manual Pnmtopnm User Manual(1)
NAME
pnmtopnm - copy a PNM image
SYNOPSIS
pnmtopnm
[pnmfile]
DESCRIPTION
This program is part of Netpbm(1).
pnmtopnm simply copies a PNM image to Standard Output. The output has
the same major PNM format (PBM, PGM, or PPM) and maxval as the input.
This may seem an unnecessary duplication of cat, but it lets you convert
between the plain (ASCII) and raw (binary) subformats of PNM. Use the
-plain Netpbm common option to ensure the output is plain PNM, and don't
use -plain to ensure the output is raw PNM. See ]8;;index.html#commonoptions\ Common Options]8;;\ .
You don't normally need to convert between the PNM subformats, because
any program that uses the Netpbm library to read a PNM image will read
all of them directly. But there are a lot of programs that don't use
the Netpbm library and understand only the raw format. Plain format is
nice because it is human readable; people often use it to debug programs
that process PNM images.
pnmtopnm is really just another name for the program pamtopnm. The lat-
ter does the job because like any Netpbm program that takes PAM input
via the Netpbm programming library facilities, it also takes PNM input.
OPTIONS
There are no command line options defined specifically for pnmtopnm, but
it recognizes the options common to all programs based on libnetpbm (See
]8;;index.html#commonoptions\ Common Options]8;;\ .)
HISTORY
pnmtopnm was new in Netpbm 10.23 (July 2004). It obsoleted pnmto-
plainpnm, which specifically did the conversion to plain PNM. There was
no program to explicitly convert to raw PNM, but many Netpbm programs
can be made, with the right options, to be idempotent (i.e. to do the
same thing as pnmtopnm).
Then David Jones realized that the existing pamtopnm already did every-
thing that pnmtopnm did and more, so in Netpbm 10.27 (March 2005), pnm-
topnm became simply an alternate name for pamtopnm.
SEE ALSO
ppmtoppm(1) pgmtopgm(1) pamtopnm(1) pnm(1)
DOCUMENT SOURCE
This manual page was generated by the Netpbm tool 'makeman' from HTML
source. The master documentation is at
http://netpbm.sourceforge.net/doc/pnmtopnm.html
netpbm documentation 24 March 2005 Pnmtopnm User Manual(1)
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