old_contents: #
  # PSNR.py
  # Created by pira on 2017/08/15.
  #
  
  #coding: utf-8
  
  from VideoDigitalWatermarking import *
  import numpy as np
  
  a = np.array([[[11,10,10],[20,20,20],[30,30,30]],[[10,10,10],[20,20,20],[30,30,30]],[[10,10,10],[20,20,20],[30,30,30]]])
  b = np.array([[[10,10,10],[20,20,20],[30,30,30]],[[10,10,10],[20,20,20],[30,30,30]],[[10,10,10],[20,20,20],[30,30,30]]])
  c = np.array([[[10,10,10],[20,20,20],[30,30,30]],[[10,10,10],[20,20,20],[30,30,30]],[[10,10,10],[20,20,20],[30,30,30]]])
  
  psnr = calcPSNR(a, b)
  print('PSNR =', psnr)
  
  psnr = calcPSNR(b, c)
  print('PSNR =', psnr)
new_contents: #
  # PSNR.py
  # Created by pira on 2017/08/15.
  #
  
  #coding: utf-8
  
  from VideoDigitalWatermarking import *
  import numpy as np
  
  a = np.array([[[11,10,10],[20,20,20],[30,30,30]],[[10,10,10],[20,20,20],[30,30,30]],[[10,10,10],[20,20,20],[30,30,30]]])
  b = np.array([[[10,10,10],[20,20,20],[30,30,30]],[[10,10,10],[20,20,20],[30,30,30]],[[10,10,10],[20,20,20],[30,30,30]]])
  c = np.array([[[10,10,10],[20,20,20],[30,30,30]],[[10,10,10],[20,20,20],[30,30,30]],[[10,10,10],[20,20,20],[30,30,30]]])
  
  psnr = calcPSNR(a, b)
  print('PSNR =', psnr, '[dB]')
  
  psnr = calcPSNR(b, c)
  print('PSNR =', psnr, '[dB]')
subject: rewrite PSNR sample