DoorMonitor - Doggy Motion Capture

ruby_home_automation_for_canine_happiness.rb

require 'rubygems'
require 'directory_watcher'
require 'fileutils'
require 'growl'
# require 'ruby_gntp'
SOURCE    = "http://172.16.187.5/img/mjpeg.cgi" #URL source of your video stream
#SOURCE    = "http://172.16.187.5/img/video.asf" #URL source of your video stream
INTERVAL  = 2 #seconds between frame grabs
FUZZ      = 10 #fuzz for dealing with lossy jpgs
MIN_DELTA = 5 #delta required to cause a notification to occur
MESSAGE   = "The Dogs want out!" #message to show
class DoorMonitor
  attr_accessor :frame_size, :last_frame, :current_frame, :ffmpeg_pid, :ffmpeg_process, :frames_changed, :last_notification, :delta
  def compare_frames
    self.frame_size ||= eval(`identify #{current_frame}`.split(" ")[2].gsub("x","*"))
    difference = `compare -metric AE -fuzz #{FUZZ}% #{last_frame} #{current_frame} null 2>&1`.to_i
    self.delta = (100.00*difference/frame_size).to_i
    print("\r#{Time.now.strftime '%b %e %l:%M:%S%P'} %3d%" % delta);STDOUT.flush
    notify if delta >= MIN_DELTA #|| File.basename(current_frame, ".jpg").to_i % 4 == 1
  end
  def run
    #start with a clean dir
    FileUtils.rm_rf "frames"
    FileUtils.mkdir_p "frames"
    self.last_notification = Time.now - 360
    dw = DirectoryWatcher.new 'frames/', :glob => '*.jpg', :interval => INTERVAL
    dw.add_observer do |*args|
      args.each do |event|
        if event.type.to_s == 'added' && event.path !~ /notify/
          #nuke the old frame
          FileUtils.rm_f self.last_frame if self.last_frame && ENV['CLEANUP'] != 'off'
          self.last_frame = self.current_frame
          self.current_frame = event.path
        end
      end
      #compare frames if we have two of them and we have new frames according to DirWatcher
      compare_frames if self.last_frame
    end
    dw.start

    #start ffmpeg
    self.ffmpeg_process = IO.popen("ffmpeg -i #{SOURCE} -y -ss #{INTERVAL} -an -sameq -f image2 -r 1/#{INTERVAL} frames/%07d.jpg </dev/null 2>&1")
    self.ffmpeg_pid = self.ffmpeg_process.pid
    puts "ffmpeg pid: #{ffmpeg_pid}"

    # when the user hits "q" the script will terminate
    while gets.strip != 'q'
    end
    dw.stop

  end
  protected
    def notify
      #don't go nuts on the notification
      return unless (Time.now - self.last_notification) > 1.minute
      self.last_notification = Time.now
      #make a copy of the frame for safe keeping
      notify_frame = "frames/notify-#{Time.now.strftime "%Y%m%d%H%M%S"}.jpg"
      FileUtils.cp current_frame, notify_frame

      Growl.notify do |n|
        n.message = MESSAGE
        n.image = File.expand_path(notify_frame)
        n.name = "door_monitor"
        n.title = "Door Monitor"
        n.sticky!
      end
    end
end

door_monitor = DoorMonitor.new
door_monitor.run