Colorscore is a simple library that uses ImageMagick to quantize an image and find its representative colors. It can also score those colors against a palette using the CIE2000 Delta E formula. This could be used to index images for a "search by color" feature.
- ImageMagick 6.5+
include histogram = Histogram.new('test/fixtures/skydiver.jpg') # This image is 78.8% #7a9ab5: histogram.scores.first # => [0.7884625, RGB [#7a9ab5]] # This image is closest to pure blue: palette = Palette.from_hex(['ff0000', '00ff00', '0000ff']) scores = palette.scores(histogram.scores, 1) scores.first # => [0.16493763694876, RGB [#0000ff]]