ImageMagick supports the same function using the

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`-level`

*(not discussing APIs)*. This is documented here

According to the docs, one can specify

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`-level black_point,white_point`

*(not interested in gamma at this point)*.

The range for these parameters is 0 to

*QuantumRange*, or from 0 to 100%. "

*QuantumRange*" being the maximum possible value according to pixel depth. For 8bit/channel RGB images (the usual), it would be 255.0.

It also says:

Now here is my problem:If a % sign is present anywhere in the string, both black and white points are percentages of the full color range.

This works fine, when using percentages:

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`convert SOME_IMAGE -level 10%,90% OUTPUT_IMAGE`

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`convert SOME_IMAGE -level 92,243 OUTPUT_IMAGE`

I've also looked here but all examples are using percentages.

How can I apply a "Levels" with ImageMagick, preferably without resorting to

**bc**to perform floating point percentage calculations from my actual numerical values?

Thank you.

Tested with

Version: ImageMagick 6.8.6-10 2016-05-30 Q16