Greyscale image to bitonal

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glennrp
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Joined: 2006-04-01T08:16:32-07:00
Location: Maryland 39.26.30N 76.16.01W

Post by glennrp »

  • -threshold
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anthony
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Post by anthony »

If the pixels are pure and your IM is a Q16 then use..

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2^16 - 2   => 65534
EG:

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-threshold 65534
or more simply for all IM Q, negate the image threshold and negate back, so you don't have to deal with the color range.

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 -negate  -threhold 0  -negate
NOTE: if you want to make ALL pixels black, use a -threshold of '-1'
See
http://www.cit.gu.edu.au/~anthony/graph ... vas/#other
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
https://imagemagick.org/Usage/
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