random_avt.rb

require 'RMagick'
 
w = 64
h = 32
canvas = Magick::Image.new(w, h) {
  self.format = 'png'
}

Magick::Draw.new.tap do |dr|
  prng = Random.new
  (0...w).each do |x| 
    (0...h).each do |y| 
      dr.fill "##{ prng.rand(16777216).to_s(16).rjust(6,'0') }"
      dr.point(x, y)
    end
  end
  dr.draw canvas
end
 
bin = canvas.to_blob