Manual: pamvalidate

Pamvalidate User Manual(1)			   General Commands Manual			  Pamvalidate User Manual(1)

NAME
       pamvalidate - validate Netpbm image format

SYNOPSIS
       pamvalidate

DESCRIPTION
       This program is part of Netpbm(1).

       pamvalidate copies a Netpbm image from Standard Input to Standard Output, except that if there are certain violations
       of the image format in the input, pamvalidate fails without producing any output.

       This  is	 most useful in a pipeline, before a stage you don't want to start working on Netpbm input until it knows it
       can get all the way through it.	For example, assume you are converting PPM images to PNG and you don't want to	pro‐
       duce  a	partial	 PNG  file under any circumstance.  If you just use pnmtopng, and the PPM input is truncated halfway
       through the raster, pnmtopng fails, but also produces about half of a PNG file.	To prevent that, pass your PPM input
       through pamvalidate on its way to pnmtopng.  Then, pamvalidate will fail, and consequently the  pipeline	 will  fail,
       before pnmtopng has seen any input and therefore before pnmtopng has produced any output.

       These are the kinds of format violations pamvalidate detects:

       •      A purported sample value exceeds the declared maxval.

       •      The stream ends prematurely.

       This program works on multi-image streams, producing a corresponding output stream.

       See pamfix for a way to salvage an invalid Netpbm image stream.

OPTIONS
       There  are  no command line options defined specifically for pamvalidate, but it recognizes the options common to all
       programs based on libnetpbm (See	 Common Options .)

SEE ALSO
       pam(1) pnm(1) pamfix(1)

HISTORY
       pamvalidate was new in Netpbm 10.66 (March 2014).

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/pamvalidate.html

netpbm documentation					22 March 2014				  Pamvalidate User Manual(1)