[PD] Can GEM select a color from an image?

[Mathieu Bouchard]

On Sun, 11 Sep 2011, Olivier B wrote:

> I think [pix_mean_color] is what you need.

This only finds the average colour, which is usually not the same as the 
most prevalent colour, even though it is the best estimator.

The best estimator means that it's your best guess when someone asks you 
to predict pixels picked randomly in the image. It leads to least square 
error : (predicated - random)² is as low as it can be, on the long term.

In statistics, we learn about Average, Median and Mode, usually all 3 at 
once, as 3 basic approaches, three kinds of «middles» of the data. What 
Sebastian is looking for is more like Mode, which looks like the easiest 
of the 3, but is actually the hardest of the 3, especially when doing in 
multidimension spaces (such as red,green,blue) and on continuous scales 
(256 values per dimension is continuous enough for what I'm talking 
about).

There are several gotchas about peaks in statistical distributions.

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