Xyz is an additive color space based on how the eye intereprets stimulus from light. Unlike other additive rgb like Rgb, Xyz is a purely mathmatical space and the primary components are "imaginary", meaning you can't create the represented color in the physical by shining any sort of lights representing x, y, and z. It's complicated to explain in a nutshell, so read more about it here:
Hsl is a cylindrical-coordinate representation of the Rgb color model. This representation rearranges the colors in an attempt to be more intuitive and perceptually relevant than the typical Rgb representation. It's frequently used for computer graphics applications like color pickers and image analysis.
Color conversions performed using the open source ColorMine library.
Cool! Creating famous images from color palettes found in other images: http://t.co/H1OxefkOt0