anchor.diff:  ----
   
   Variable *gray_image* stores now grayscale image, each pixel has value in range from 0 to 1.
  -After this step we can treshold the image using provided treshold value:
  +Next the script performs tresholding of the image using provided treshold value:
   
   [source,python]
   ----
  
positive.code: 
  == Python code step by step
  
  Our application will have input parameter provided from console. We will require:
  
  - path to the image file
  - integer indicating minimum size in pixels for a shape
  - float value between 0 and 1 as a threshold
  
  In the following block of code we check if user provided all the required parameters and whether they have valid values:
  
  [source,python]
  ----
  
negative.code:     main()
  ----
  
  Once script has a valid input we can begin the image processing.
  First script needs to load the image and turn it into grayscale. This is done using link:http://scikit-image.org/docs/dev/api/skimage.io.html#imread[imread] and link:http://scikit-image.org/docs/dev/api/skimage.color.html#rgb2gray[rgb2gray] functions.
  
  [source,python]
  ----
  