A quick question about multiply

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A quick question about multiply

Post by thanhhuyen8653 » 2018-07-10T18:26:30-07:00

Sorry if this is a simple question, but I can't find info online.

I have substracted two images and would like scale the resulting diff image by some constant to make differences more noticeable. I'd imagine ImageMagick is able to do this, but I can't find the right commands for this. Can anyone point me to the right place, documentation?

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Re: A quick question about multiply

Post by fmw42 » 2018-07-10T18:35:47-07:00

You could just use -auto-level. It would automatically stretch the dynamic range to full black and full white.

Alternately, you can use -evaluate multiply X, where X is some multiplier factor.

http://www.imagemagick.org/script/comma ... auto-level
http://www.imagemagick.org/script/comma ... p#evaluate

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Re: A quick question about multiply

Post by snibgo » 2018-07-11T02:49:29-07:00

The identical question was asked, and answered, four years ago.

The spammer is now banned.
snibgo's IM pages: im.snibgo.com

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