Cross-posting from https://forrst.com/posts/Collecting_colours_from_an_image_Ruby-Lgo Collecting colours from an image with Ruby

parse_colors.rb

require 'rmagick'
number_of_colors = 100
file_path = "/path/to/file.jpg"
begin
  temp_file = Magick::Image.read(file_path).first.quantize(number_of_colors)
  pixels = {}
  pixel_count = 0
  temp_file.each_pixel do |p,c,r|
    pixel_count += 1
    pix = p.to_color(Magick::AllCompliance, false, 8)
    pixels[pix] = (pixels[pix] || 0) + 1
  end
  puts "Pixels: #{pixel_count}"
  pixels.sort { |a,b| b[1] <=> a[1] }
rescue Magick::ImageMagickError
  {}
end