Is HSL Superior over HSI and HSV Color Spaces?

image-processing colors computer-vision color-space
user1509260 picture user1509260 · Jul 9, 2012 · Viewed 15.4k times · Source

Is HSL superior over HSI and HSV, because it takes human perception into account.? For some image processing algorithms they say I can use either of these color spaces, and I am not sure which one to pick. I mean, the algorithms just care that you provide them with hue and saturation channel, you can pick which color space to use

Answer

Mark Ransom picture Mark Ransom · Jul 9, 2012

Which one is best very much depends on what you're using it for. But in my experience HSL (HLS) has an unfortunate interaction between brightness and saturation.

Here's an example of reducing image brightness by 2. The leftmost image is the original; next comes the results using RGB, HLS, and HSV:

RGB, HLS, HSV comparison

Notice the overly bright and saturated spots around the edge of the butterfly in HLS, particularly that red spot at the bottom. This is the saturation problem I was referring to.

This example was created in Python using the colorsys module for the conversions.

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