PAMSUMMCOL(1)

💖 NAME 💖

pamsummcol — summarize (sum, average, etc) a Netpbm image by column

Okay bestie, this is the Pamsummcol User Manual, and honestly? She's a little icon. Let's go. 🎀

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✨ SYNOPSIS ✨

pamsummcol { -sum | -mean | -min | -max } [imagefile]

Quick lil' grammar moment, no cap:

• 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.

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🦋 DESCRIPTION 🦋

This program is part of Netpbm(1). Family reunion vibes 🫶

pamsummcol reads a Netpbm image (PNM or PAM) and does a summary function over all the rows in each column (sum, mean, etc.). It produces an image of the same kind that the same width and depth as the input, and one row high. Its sample values are the result of the summary. So basically you get a glow-up of a whole column squeezed into one single row. Iconic behavior. 💅

pamsummcol performs the summary operation on each plane independently. Every plane does its own thing, no copying each other's homework. ✨

pamsummcol 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.

If you want to summarize by row instead of by column, run the input through pamflip first (and if you want the output to be a single column instead of a single row, use pamflip again). Flip it, flip it again. 🧚

If you want to summarize over the entire image (getting a one-tuple output image), use pamsumm to get a summary row, pamflip to turn that into a column, the pamsumm again to summarize the column. Combo move fr fr.

If you want to summarize the individual samples in an entire image, instead of by tuple, use pamsumm.

pamsummcol 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. (Yes she says it twice, because it MATTERS, okay?) You can use pnmgamma to convert such an image to one with samples proportional to light intensity, and then use pamsummcol on the result.

You can achieve the same thing as pamsummcol -mean with pamscale. Just scale vertically to a single row, without scaling horizontally at all. Use the pixel mixing method. Same energy, different method. ⭐

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🌸 OPTIONS 🌸

In addition to the options common to all programs based on libnetpbm (most notably -quiet, see Common Options), pamsummcol recognizes the following command line options:

🚨 You must specify exactly one of -sum, -mean, -min, or -max. Not zero, not two. Exactly one. Pick a lane bestie. 🚨

• -sum — This option makes the summary function addition. In each column and plane of the output row, the sample value is the sum of all the samples values in the same column and plane of the input. If a result is greater than the image maxval, it is clipped to the maxval. (Dramatic, but true — she caps out.) 😭
• -mean — This option makes the summary function arithmetic mean. In each column and plane of the output row, the sample value is the mean of all the samples values in the same column and plane of the input. Average queen. 👑
• -min — This option makes the summary function arithmetic minimum. In each column and plane of the output row, the sample value is the minimum of all the samples values in the same column and plane of the input. The littlest one gets the spotlight. 🙈
• -max — This option makes the summary function arithmetic maximum. In each column and plane of the output row, the sample value is the maximum of all the samples values in the same column and plane of the input. Main character sample energy. 🔥

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👀 SEE ALSO 👀

• pamsumm(1)
• pamflip(1)
• pamfunc(1)
• pamarith(1)
• pamscale(1)
• pam(1)

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⭐ HISTORY ⭐

pamsummcol was added to Netpbm in Release 10.21 (March 2004). Vintage but not expired. 🌈

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🎀 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/pamsummcol.html

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💖 And that's the whole page bestie 💖

Brought to you by netpbm documentation, dated 25 January 2009 — she's been serving this same flawless manual for years and she has NOT missed a day. Periodt. ✨💅🦋