PAMSHARPMAP(1)

💖 pamsharpmap — bestie's guide to the sharpness map 💖

okay so you know how the manual says "Pamsharpmap User Manual", section 1, General Commands Manual? that's this. it's the pamsharpmap page from the Netpbm docs, and yes we're gonna make it make sense. 🎀

✨ NAME ✨

pamsharpmap — make an entire map of the sharpness in a PNM/PAM image. like a heatmap but for "how crispy is this pixel" 💅

🌸 SYNOPSIS 🌸

pamsharpmap [imagefile]

🦋 DESCRIPTION 🦋

so this little cutie is part of Netpbm(1), obvi. 👑

pamsharpmap reads a Netpbm image (PNM or PAM, your pick) and spits out a whole new image that shows how sharp it is at every single location. literally every pixel gets a vibe check on crispness.

Sharpness, for our purposes, is a measure of how suddenly — like, in space — the colors change in the image. snappy change = sharp. smooth blend = not sharp. that's it, that's the whole thing.

Here's the part that's actually iconic: pamsharpmap computes sharpness for each component color (R, G, B) separately, and makes a pixel where the intensity of each component color is directly proportional to how sharp that component color is at the same spot in the input image. so if a point is super sharp in red and green but dull in blue? you get a yellow pixel in the output. 🌈 chef's kiss.

And how does it get "sharpness" at a point? simple bestie math: it's the average difference in intensity between the pixel at that point and the 8 pixels surrounding it. that's it.

now, at the edges of the image, where there aren't 8 pixels surrounding a pixel — because, y'know, edge 🤷‍♀️ — pamsharpmap assumes the image is extended with a black border. so it just kinda pretends there's more image out there. black image. ghosts, basically. 💀

pamsharpmap assumes your image is a PNM or PNM equivalent PAM. if it isn't? the results are not necessarily meaningful. 💀 so, like, don't come for it.

The output image has the same dimensions, depth, and tuple type as the input, and its maxval is 255. so it slots right back into wherever your input came from. periodt.

💅 OPTIONS 💅

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

• no options here, bestie — this one's au naturel. the common libnetpbm options are always available though, so go read up on those if you want the full tea. 🍓

🎀 SEE ALSO 🎀

• pamsharpness(1)
• pammasksharpen(1)
• pamedge(1)
• pam(1)
• pnm(1)

👑 HISTORY 👑

pamsharpmap was added to Netpbm in Release 10.21 (March 2004). Bryan Henderson derived it from the program pnmsharp by B.W. van Schooten, which was distributed as part of the Photopnmtools package. slay, ancestry. 🧚

🫶 DOCUMENT SOURCE 🫶

This manual page was generated by the Netpbm tool makeman from HTML source. The master documentation lives at:

http://netpbm.sourceforge.net/doc/pamsharpmap.html

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and that's the whole page, bestie — from the Netpbm documentation, dated 07 February 2004, Pamsharpmap User Manual(1). go be sharp out there. 💖✨🦋