Clustering Colors using Affinity Propagation

cluster_colors.rb

#!/usr/bin/env ruby
require 'bundler/setup'
require 'affinity_propagation'
require 'byebug'

module AffinityPropagation
  class Calculator
    attr_accessor :availabilities, :responsibilities, :similarities
  end
end

def yuv_distance(datum, exemplar)
  r_mean = (datum[:r] + exemplar[:r]) / 2
  r_delta = datum[:r] - exemplar[:r]
  g_delta = datum[:g] - exemplar[:g]
  b_delta = datum[:b] - exemplar[:b]

  (2 + r_mean / 256) * (r_delta ** 2) + 4 * (g_delta ** 2) + (2 + (255 - r_mean) / 256) * (b_delta ** 2)
end

def rgb_distance(datum, exemplar)
  r_delta = datum[:r] - exemplar[:r]
  g_delta = datum[:g] - exemplar[:g]
  b_delta = datum[:b] - exemplar[:b]

  (r_delta ** 2) + (g_delta ** 2) + (b_delta ** 2)
end

def uv_distance(datum, exemplar)
  u_delta = datum[:u] - exemplar[:u]
  v_delta = datum[:v] - exemplar[:v]

  (u_delta ** 2) + (v_delta ** 2)
end

def rgb_output(datum)
  [datum[:r], datum[:g], datum[:b]].join(' ')
end

def uv_output(datum)
  [datum[:u], datum[:v]].join(' ')
end

html_colors = []

File.open("html-colors.dat", "w") do |all_colors_file|
  File.open("selected-html-color-codes.txt").each.map do |line|
    next if line =~ /^\s*$/ # skip blank lines
    next if line =~ /^#/  # skip comments

    name, color, family = line.chomp.split(',')
    r, g, b = color.gsub(/(.{2})(.{2})(.{2})/, '\1,\2,\3').split(',').map { |c| c.to_i(16) }
    y = r *  0.299000 + g *  0.587000 + b *  0.114000
    u = r * -0.168736 + g * -0.331264 + b *  0.500000 + 128
    v = r *  0.500000 + g * -0.418688 + b * -0.081312 + 128

    datum = {
      name: name,
      family: family,
      r: r,
      g: g,
      b: b,

      y: y,
      u: u,
      v: v
    }

    all_colors_file << uv_output(datum)
    all_colors_file << "\n"

    html_colors << datum
  end
end

apc = AffinityPropagation::Calculator.new(html_colors, lambda: 0.75) do |datum, exemplar|
  # distance = rgb_distance(datum, exemplar)
  # distance = yuv_distance(datum, exemplar)
  distance = uv_distance(datum, exemplar)

  -distance
end

apc.run(iterations: 10_000, stable_iterations: 50) do |iteration, stable_iterations|
  clusters = apc.clusters

  puts "Iterations: #{apc.total_iterations} - Stable: #{apc.stable_cluster_iterations} - Found #{clusters.size} clusters"

  File.open('clustered-html-colors.dat', 'w') do |file|
    clusters.each do |cluster|
      exemplar = cluster[:exemplar]
      file << uv_output(exemplar)
      file << "\n"
    end
  end

  `gnuplot -e 'set title "Iter: #{apc.total_iterations}, Stable: #{apc.stable_cluster_iterations}, Found: #{clusters.size}"' clusters.gnuplot > scatter.#{"%05d" % apc.total_iterations}.png`
end

clusters = apc.clusters

clusters.each do |cluster|
  exemplar = cluster[:exemplar]
  puts "#{exemplar[:name]} (#{exemplar[:family]})"

  cluster[:members].each do |member|
    puts "  #{member[:name]} (#{member[:family]})"
  end
end

puts
puts "Availability Matrix:"
puts apc.availabilities

puts
puts "Responsibility Matrix:"
puts apc.responsibilities

clusters.gnuplot

# set terminal pngcairo  transparent enhanced font "arial,10" fontscale 1.0 size 600, 400 
set terminal png
set dummy u, v
set key fixed right top vertical Right noreverse enhanced autotitle box lt black linewidth 1.000 dashtype solid
# set parametric
## set title "Clustering Colors in UV-space"
set xlabel "Chrominance (U)" 
set ylabel "Chrominance (V)"
DEBUG_TERM_HTIC = 119
DEBUG_TERM_VTIC = 119
## Last datafile plotted: "html-colors.dat"
plot "html-colors.dat" title "Actual Colors", "clustered-html-colors.dat" title "Clusters"

selected-html-color-codes.txt

# Red Colors
IndianRed,CD5C5C,Red
LightCoral,F08080,Red
Salmon,FA8072,Red
DarkSalmon,E9967A,Red
LightSalmon,FFA07A,Red
Crimson,DC143C,Red
Red,FF0000,Red
FireBrick,B22222,Red
DarkRed,8B0000,Red

# Pink Colors
Pink,FFC0CB,Pink
LightPink,FFB6C1,Pink
HotPink,FF69B4,Pink
DeepPink,FF1493,Pink
MediumVioletRed,C71585,Pink
PaleVioletRed,DB7093,Pink

# Orange Colors
LightSalmon,FFA07A,Orange
Coral,FF7F50,Orange
Tomato,FF6347,Orange
OrangeRed,FF4500,Orange
DarkOrange,FF8C00,Orange
Orange,FFA500,Orange

# Yellow Colors
Gold,FFD700,Yellow
Yellow,FFFF00,Yellow
LightYellow,FFFFE0,Yellow
LemonChiffon,FFFACD,Yellow
LightGoldenrodYellow,FAFAD2,Yellow
PapayaWhip,FFEFD5,Yellow
Moccasin,FFE4B5,Yellow
PeachPuff,FFDAB9,Yellow
PaleGoldenrod,EEE8AA,Yellow
Khaki,F0E68C,Yellow
DarkKhaki,BDB76B,Yellow

# Purple Colors
Lavender,E6E6FA,Purple
Thistle,D8BFD8,Purple
Plum,DDA0DD,Purple
Violet,EE82EE,Purple
Orchid,DA70D6,Purple
Fuchsia,FF00FF,Purple
Magenta,FF00FF,Purple
MediumOrchid,BA55D3,Purple
MediumPurple,9370DB,Purple
Amethyst,9966CC,Purple
BlueViolet,8A2BE2,Purple
DarkViolet,9400D3,Purple
DarkOrchid,9932CC,Purple
DarkMagenta,8B008B,Purple
Purple,800080,Purple
Indigo,4B0082,Purple
SlateBlue,6A5ACD,Purple
DarkSlateBlue,483D8B,Purple
MediumSlateBlue,7B68EE,Purple

# Green Colors
GreenYellow,ADFF2F,Green
Chartreuse,7FFF00,Green
LawnGreen,7CFC00,Green
Lime,00FF00,Green
LimeGreen,32CD32,Green
PaleGreen,98FB98,Green
LightGreen,90EE90,Green
MediumSpringGreen,00FA9A,Green
SpringGreen,00FF7F,Green
MediumSeaGreen,3CB371,Green
SeaGreen,2E8B57,Green
ForestGreen,228B22,Green
Green,008000,Green
DarkGreen,006400,Green
YellowGreen,9ACD32,Green
OliveDrab,6B8E23,Green
Olive,808000,Green
DarkOliveGreen,556B2F,Green
MediumAquamarine,66CDAA,Green
DarkSeaGreen,8FBC8F,Green
LightSeaGreen,20B2AA,Green
DarkCyan,008B8B,Green
Teal,008080,Green