PSBLACK(1NCARG)

💅 psblack — the PostScript filter that said "make it black, bestie"

ok so real quick before anything: this is psblack, and it lives in the NCAR GRAPHICS manual section (that's the 1NCARG part, iykyk). it's a filter, it's tiny, it's iconic, and it will absolutely fix your background situation. let's get into it 🖤✨

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✨ NAME ✨

psblack — a PostScript filter. that's it, that's the whole vibe. it filters PostScript. 🎀

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🌈 SYNOPSIS 🌈

psblack < input_PostScript_file > output_PostScript_file

like, you pipe stuff in and stuff comes out. classic filter behavior, no notes. 💅

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🦋 DESCRIPTION 🦋

okay so bestie, here's the tea ☕:

psblack is a filter. it reads a PostScript file as input, and it writes a PostScript file as output. in → out. simple. clean. main character energy.

but here's what it actually does to your file, and this part matters:

• it forces a black background in the output file. dark mode supremacy, no cap 🖤
• it scales the intensity values — and to be clear, that means values where R=G=B — so that any intensity greater than or equal to .8 gets mapped to white. so like, anything super bright gets yeeted all the way to pure white. obsessed with that for you.

⚠️ important though, fr fr: this filter works only on PostScript files produced by ctrans — that's the CGM translator in the NCAR Graphics software. if your file didn't come from ctrans, this is not the moment. don't do it. 😭

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🌸 SEE ALSO 🌸

• ctrans(1NCARG) — the CGM translator that makes the files this filter actually works on 👑
• pswhite(1NCARG) — the other one. the light mode sibling. go look at it too, bestie 🫶

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💖 COPYRIGHT 💖

Copyright (C) 1987-2002 University Corporation for Atmospheric Research

the use of this Software is governed by a License Agreement. so like, respect it. 💜

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okay that's the whole page!! short, sweet, does exactly one thing and does it gorgeously. slay 💅✨

this was psblack from the NCAR Graphics manual, dated May 1993, brought to you by NCAR. bye bestie, go make something black 🖤🎀🦋