Normalize RGB *together* (rather than seperately)?

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magick
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Post by magick » 2005-11-16T20:57:52-07:00

You can multiply each channel with the -evaluate or -fx options.

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anthony
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Post by anthony » 2005-11-17T20:59:10-07:00

The problem appears to be that -normalize is a grey scale operator
whcih works on each channel seperatally. It isn't really designed for
handling RGB images as such.

Such an operation for RGB is usally designed to not only expand the
three color channels together, but also use a 'threshold' level of some sort
which defines the 'greyscaled' level greyscale histogram of the image
to ignore.

That is it doesn't expand all the colors, but the area where most of the colors which lie on the images hisogram. Much more complicated affair.

Can anyone further expand on this problem whcih was also seen as a color tinitng problem in a previous forum thread.
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
https://imagemagick.org/Usage/

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magick
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Post by magick » 2005-11-19T19:32:45-07:00

Post your patch or a URL to your patch so we can review your mods. We can accomodate both methods, normalizing a channel and normalizing the image.

cra3y

Post by cra3y » 2006-05-03T14:06:39-07:00

Is pflangfel's normalize patch has been applied into ImageMagick?

If it is true, which command line parameter run pflangfel's normalize ?(-normalize works in old-way method, normalizing each channels separately)

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Post by anthony » 2006-05-07T22:48:17-07:00

Actually it doesn't and hasn't for some time.

See notes on normalize in IM Examples..
http://www.cit.gu.edu.au/~anthony/graph ... #normalize
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
https://imagemagick.org/Usage/

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