'''This module defines the XImage class, which extends the PIL Image class.

Jeff Ondich, 16 Feb 2007, for CS 117.

For the assignment due on 21 Feb 2007, your job is to complete the toGray,
reflect, tile, addFakeScratches, and medianFilter methods as described in the
comments below.

This program will require you to install PIL (the Python Imaging Library), which
you can get from http://www.pythonware.com/products/pil/ if it's not already
installed on the computer you are using.  It is already installed in the CS labs
in the CMC.
'''

import Image
import time

class XImage:
    def __init__(self, fileName):
        self.imageFileName = fileName
        self.image = Image.open(self.imageFileName)

    def show(self):
        '''
        Display this image.  On some systems, the program will not
        continue execution until after you close the image window.
        On other systems, it will.
        '''
        self.image.show()

    def revert(self):
        '''
        Restore this image to the image stored in the original image file.
        '''
        self.image = Image.open(self.imageFileName)

    def save(self, fileName):
        '''
        Save this image to the file specified by the string fileName.  If fileName
        ends in '.jpg', the image will be stored as a JPEG file.  '.png', '.bmp',
        '.gif', '.tiff', etc. behave similarly.
        '''
        self.image.save(fileName)

    def toGreen(self):
        '''
        Removes all the red and blue from this image.
        '''
        pixels = self.image.load()
        for y in range(self.image.size[1]):
            for x in range(self.image.size[0]):
                greenValue = pixels[x, y][1]
                pixels[x, y] = (0, greenValue, 0)

    def toGray(self):
        '''
        Turns this image into a black-and-white image.  That is, each pixel is changed to
        a shade of gray.  Do this by setting the red, green, and blue values of each pixel to
        the average of its original red, green, and blue values.
        '''
        pass

    def reflect(self):
        '''
        Transforms this image to a left-to-right mirror image of itself.
        '''
        pass

    def tile(self, squareWidth):
        '''
        Treating this image as though it is a chess board of squares of width and height given
        by the integer parameter squareWidth, this method turns every other square upside-down
        using a top-to-bottom mirror image.  Another way of thinking of it would be to superimpose
        a chess board on the image.  Then, leave the white squares alone, but flip the black squares
        upside-down.
        '''
        pass

    def addFakeScratches(self):
        '''
        Adds some white pixels to an image to stand in for "scratches" on the
        surface of a photograph.  My version of this method does diagonal white lines
        50 pixels apart, but you can do anything that adds a reasonable number
        of unexpected white pixels to the image.  (Vertical or horizontal lines
        are probably easier to draw, and would be perfectly acceptable.)
        '''
        pass

    def medianFilter(self):
        '''
        Applies a median filter to this image, using a 3x3 square neighborhood of
        each pixel.  For each pixel, you will collect the set of red values in the
        neighborhood of the pixel, and use the median of those values as the new red
        value of the pixel.  Do the same for the green and blue values, as discussed
        in class.
        the 
        '''
        pass

if __name__ == '__main__':
    image = XImage('babe.jpg')

    image.show()
    s = raw_input('type something to continue')

    image.toGreen()
    image.show()
    s = raw_input('type something to continue')

    image.revert()
    image.toGray()
    image.show()
    s = raw_input('type something to continue')

    image.revert()
    image.reflect()
    image.show()
    s = raw_input('type something to continue')

    image.revert()
    image.tile(150)
    image.show()
    s = raw_input('type something to continue')

    image.revert()
    image.addFakeScratches()
    image.show()
    s = raw_input('type something to continue')

    image.medianFilter()
    image.show()
    s = raw_input('type something to continue')