histogram
Show the statistical distribution of color channel values inside an image.
var i = g.import('leaf.jpg');
g.histogram(i, 'lum');
Parameters
image: The input image.channel: The channel to get the values from, either of ‘lum’ (luminance of the pixel), ‘red’, ‘green’, ‘blue’ and ‘alpha’ values.relative: When true, divide the numbers in the list so that their sum total becomes 1, otherwise just return the number of occurrences.