''' Purpose: support image palette reduction transformation
'''

def size( original ) :
    ''' Purpose: return the size of the new image when performing a palette
            reduction
    '''

    nw, nh = original.size

    return (nw, nh)


def distance( p1, p2 ) :
    ''' Returns the distance between p1 and p2; that is the sum of the
        red differences, green differences, and blue differences, where
        difference is an absolute value.
    '''

    pass

def color( opixel ) :
    ''' Returns the pixel in PALETTE8 to which opixel is closest
    '''

    PALETTE8 = [ (  0,  0,  0), (255,255,255), (  0,255,  0), (  0,  0,255),
                 (255,  0,  0), (255,255,  0), (255,  0,255), (  0,255,255) ]

    pass

def where( nspot, original = None ) :
    ''' Purpose: return the correspondent of nspot in the original when
            doing a palette reduction
    '''

    ospot = nspot

    return ospot

if ( __name__ == '__main__' ) :

    import url
    from manip import manip
    
    # get web image of interest
    link = "http://www.cs.virginia.edu/~cs1112/images/mandrill/full.png"

    original = url.get_image( link )

    new_image = manip( original, size, color, where )

    new_image.show()