Ruby OpenCV

visualizator.rb

require "opencv"
include OpenCV

WINDOW_NAME = "Difference visualization"

# read videostream from camera
camera = OpenCV::CvCapture.open(0)
# open simple window wedget
# can show (CvMat/IplImage)
window = OpenCV::GUI::Window.new(WINDOW_NAME)

def image_diff(img0, img1, img2)
  d1 = img2.abs_diff(img1)
  d2 = img1.abs_diff(img0)
  d1.and(d2)
end

# First read 3 images
t_minus = camera.query()
t = camera.query()
t_plus = camera.query()

while true
  image = camera.query
  window.show(image_diff(t_minus, t, t_plus))
  
  # Read next image
  t_minus = t
  t = t_plus
  t_plus = camera.query()#[1]

  key = OpenCV::GUI::wait_key(10)
  # ESC is pressed
  if key == 1048603
    window.destroy()
    break
  end
end

puts "Goodbye"