Implements the feature extraction part of the algorithm

dst = obj.extractSimpleFeatures(src)

Input

• src Input 3-channel image (BGR color space is assumed).

Output

• dst An array of four (r,g) chromaticity tuples corresponding to the features listed below.

In accordance with [Cheng2015], computes the following features for the input image:

1. Chromaticity of an average (R,G,B) tuple
2. Chromaticity of the brightest (R,G,B) tuple (while ignoring saturated pixels)
3. Chromaticity of the dominant (R,G,B) tuple (the one that has the highest value in the RGB histogram)
4. Mode of the chromaticity palette, that is constructed by taking 300 most common colors according to the RGB histogram and projecting them on the chromaticity plane. Mode is the most high-density point of the palette, which is computed by a straightforward fixed-bandwidth kernel density estimator with a Epanechnikov kernel function.