Pamsumm User Manual

Section: Misc. Reference Manual Pages (0)
Updated: 07 February 2004
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NAME

pamsumm - Summarize the samples in a Netpbm image arithmetically

 

SYNOPSIS

pamsumm { -sum | -mean | -min | -max } [-normalize] [-brief] [imagefile]

All options can be abbreviated to their shortest unique prefix. You may use two hyphens instead of one. You may separate an option name and its value with white space instead of an equals sign.

 

DESCRIPTION

This program is part of Netpbm(1).

pamsumm reads a Netpbm image (PNM or PAM) and performs a summary function over all the samples in all the rows, columns, and planes and prints the result to Standard Output.

pamsumm performs the operation on the actual sample values, not on the light intensities represented by them in the case that the image is a PGM or PPM image or PAM equivalent. If you want to do arithmetic on light intensities of such a visual image, you can use pnmgamma to convert it to one with samples proportional to light intensity, and then use pamsumm on the result.

If you want to summarize by column (e.g. add up the columns separately), use pamsummcol. If you want to summarize by row, use a combination of pamsummcol and pamflip. If you want to summarize a particular plane, use pamchannel to extract it and then pamsumm.

 

OPTIONS

You must specify exactly one of -sum, -mean, -min, or -max.

-sum

This option makes the summary function addition.

-mean

This option makes the summary function arithmetic mean.

-min

This option makes the summary function arithmetic minimum.

-max

This option makes the summary function arithmetic maximum.

-normalize

This option causes each sample to be normalized to a fraction
     (in the range 0..1) so the result is independent of the image's
     maxval.  E.g. if you request the mean of an image which has maxval
     200 and all the samples have value 50, pamsumm will give you
     50 as an answer.  But pamsumm -normalize will give you .25.

If you want a result that is independent of maxval but still in
     integers, and your input is PNM, you can use pamdepth to
     convert to some standard maxval.  For example, if you want the mean
     intensity of a PPM image, on a scale of 0 to 99, do


    pamdepth 99 myimage.ppm | pamsumm -mean

This option was new in Netpbm 10.22 (April 2004)
     

-brief

This option causes pamsumm to display the answer as a bare
     number, rather than in a complete sentence.

This option was new in Netpbm 10.22 (April 2004)

 

SEE ALSO

pamsumm(1), pam(1),

 

HISTORY

pamsumm was added to Netpbm in Release 10.21 (March 2004).


 

Index

NAME
SYNOPSIS
DESCRIPTION
OPTIONS
SEE ALSO
HISTORY

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