How to properly equalize the brightness of an image?

Question

Image processing

There is an image that is heavily overexposed in one area and extremely underexposed in another. I would like to get an output image that is evenly lit (even in grayscale), so that dim pixels are present along with bright ones. I looked in the direction of retinex and gamma correction, but in the case of dimly lit images they give poor results, and retinex is also quite demanding on computing resources. Maybe someone can suggest where else to look. Thank you.

Answer 1

Look here
www.fmwconcepts.com/imagemagick/
scripts like tonemap

Answer 2

Try the -equalize or -normalize options in imagemagick.

Answer 3

Convert to a representation with a selected brightness component (HSB, for example), to equalize its histogram . (perhaps this will be identical to the advice above), and then back to RGB.

Answer 4

If you need to illuminate a dark photographic image with bright spots, then there are three simple methods:
www.tankedup-imaging.com/no_flash_choice.html
For photographs of documents, when you need to get a black and white image, this option is better
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