#==============================================================================
#
# Project:   SharpImage
# Module:    ConnectedComponent.py
# Language:  IronPython
# Author:    Dan Mueller
# Date:      $Date: 2007-07-06 10:57:00 +1000 (Fri, 06 Jul 2007) $
# Revision:  $Revision: 2 $
#
# Copyright (c) Queensland University of Technology (QUT) 2007.
# All rights reserved.
#
# This software is distributed WITHOUT ANY WARRANTY; without even
# the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
# PURPOSE.  See the above copyright notices for more information.
#
#==============================================================================

# Import the base script class
import ImageToImageScript
from ImageToImageScript import *

# Add reference and import Threshold library
clr.AddReference("ManagedITK.ThresholdFilters")
from itk import *

class ConnectedComponentScript(ImageToImageScriptObject):
    # -------------------------------------------------------------------------
    Name = "ConnectedComponent"
    Help = """This filter labels the objects in a binary image.
              Each distinct object is assigned a unique label in consecutive order
              (with no gaps between the numbers used). The labels are sorted based
              on the size of the object: the largest object will have label #1,
              the second largest will have label #2, etc.
              The number of found labels is output to the script console.
              This script assumes the input image is binary in the range [0..1]."""
    Parameters = """None"""
    # -------------------------------------------------------------------------

    def ThreadedDoWork(self):
        """ Perform the main functions of the script. """
        """ NOTE: This function is invoked on a background thread. """
        try:
            self.StartedWork()
            self.WriteInputName()
            
            # Perform connected component analysis
            # NOTE: The itkConnectedComponentImageFilter expects a binary image
            #       in the range [0,1].
            filterConnected = itkConnectedComponentImageFilter.New( self.Input, self.Output )
            self.AddEventHandlersToProcessObject( filterConnected )
            filterConnected.SetInput( self.Input )
            filterConnected.FullyConnected = True

            # Relabel
            filterRelabel = itkRelabelComponentImageFilter.New( self.Input, self.Output )
            self.AddEventHandlersToProcessObject( filterRelabel )
            filterRelabel.SetInput( filterConnected.GetOutput() )
            filterRelabel.UpdateLargestPossibleRegion()
            filterRelabel.GetOutput( self.Output )
            self.DisconnectInputAndOutput()

            # Clean up
            self.DisposeOfObject( filterConnected )
            self.DisposeOfObject( filterRelabel )
            
            self.WriteOutputName()
            self.FinishedWork( True )

        except Exception, ex:
            self.HandleException( ex )
            self.FinishedWork( False )
            self.Finalise( )