Is it a good practice to use the histogram equalization on the colored image before extracting its color during a real-time video stream? I have seen some people using but I have not seen any tutorial doing that. How does it behave with luminosity changes? Are there certain cases that it might help?
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What do you mean by "before extracting its color"? – Bull Sep 06 '14 at 12:50
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yes, to pre-process the image – Vinicius Nogueira Sep 06 '14 at 14:21
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If you doing histogram equalization you need to first color convert it to a color space with a luminance channel, like Lab, HSV or YCrCb and then only equalize the luminance. If you try equalizing the RGB channels you will get weird color shifts.
Bull
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I read your post http://stackoverflow.com/questions/24341114/simple-illumination-correction-in-images-opencv-c/24341809#24341809 . Can this be applied on real time applications? – Vinicius Nogueira Sep 06 '14 at 14:32
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The full code is in that post; best to time it yourself on your images and hardware. Note that you could go MUCH faster than my implementation by using the GPU versions of cvtColor and CLAHE (possibly you need 3.0 for the latter) – Bull Sep 07 '14 at 04:53