minimagick-pixel-at-get-hex-color.rb

# get hex color of pixel
# implementation of answer here http://stackoverflow.com/questions/8894194/retrieving-the-hex-code-of-the-color-of-a-given-pixel
# solution to 'undefined method for MiniMagick::CommandBuilder in mini_magick'
require 'mini_magick'
module MiniMagick
  class Image
    def pixel_at(x, y)
      run_command("convert", "#{path}[1x1+#{x.to_i}+#{y.to_i}]", 'txt:').split("\n").each do |line|
        return $1 if /^0,0:.*(#[0-9a-fA-F]+)/.match(line)
      end
      nil
    end
  end
end

# example
image = MiniMagick::Image.open(File.expand_path('~/Desktop/truck.png'))
image.pixel_at(1,1)
#=> "#01A30D"