8bit per channel to 6bpc (RGB)

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Scorp1us
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Joined: 2010-06-23T13:37:41-07:00
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8bit per channel to 6bpc (RGB)

Post by Scorp1us »

I need to convert some images to 6bpc, which is to say that I want to zero the last 2 bits of each each RGB channel for preview on a reduced color display.

How can I do this with imagemagick?

Many thanks!
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anthony
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Joined: 2004-05-31T19:27:03-07:00
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Location: Brisbane, Australia

Re: 8bit per channel to 6bpc (RGB)

Post by anthony »

Level white to a value of 2^6-1 then +level back again. That should do the job.

convert image.png -level 0,63 +level 0,63 result.png

See 'Quantum Rounding' which is typically something to avoid, but in your case you want to do.
http://www.imagemagick.org/Usage/basics ... um_effects
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
https://imagemagick.org/Usage/
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