create animated gifs aout of a lot of screencaptures for OSX ONLY

screengif.rb

class Screengif
  attr_reader :screencapture, :convert, :tempname, :delay, :times
  def initialize args
    @screencapture = '/usr/sbin/screencapture'
    @convert = '/usr/local/bin/convert'
    args.each do |k,v|
      instance_variable_set("@#{k}", v) unless v.nil?
    end
    @tempname.gsub!("\n", '')
    (1..@times).each do |i|
      screencapture ( i == 1 ? @delay : 0.5), "#{@tempname}_#{i}.png"
      makegif "#{@tempname}_#{i}.png"
    end
    animategif "#{@tempname}_*.gif"
    cleanup
  end

  def screencapture delay, output
    `#{@screencapture} -T #{delay} #{output}`
  end

  def makegif file
    `#{@convert} #{file} #{file.gsub(/\.[a-z]{3,4}$/, '.gif')}`
  end

  def animategif files
    `#{@convert} -delay 20 -loop 0 #{files} #{@tempname}_FINAL.gif`
  end

  def cleanup
    (1..@times).each do |i|
      `rm #{@tempname}_#{i}.png #{@tempname}_#{i}.gif`
    end
  end

end

Screengif.new :delay => 5, :times => 5, :tempname => `date +%s`

ruby screengif.rb