Edgefinding code

suzan.py

# -*- coding: utf-8 -*-
"""
Created on Tue Apr 30 11:11:23 2019

@author: s3385159
"""

#Exercise 2.1

import numpy as np
from PIL import Image
import matplotlib.pyplot as plt
import matplotlib.image as mpimg

#Exercise 2.3

peer = Image.open('peer.jpg')
peer_array = np.array(peer)

def find_edges(image):
    image_array = np.array(image)
    output_array = np.array(image)
    imgHeight = len(image_array)
    imgWidth = len(image_array[0])
    biggestDiff = 0
    for y in range(len(image_array)): #loop door alle rijen pixels
        for x in range(len(image_array[y])): #loop per pixel in horizontale rij van pixels
            pixel = image_array[y][x] #hoofdpixel
            for nX in range(x-1, x+1):
                for nY in range(y-1, y+1):
                    if(not (nY == y and nX == x)):#hoofdpixel zelf uitsluiten
                        if(y >=  0 and y < imgHeight and x >= 0 and x < imgWidth): #ervoor zorgen dat je niet buiten de afbeeldinggrootte zoekt
                            neighbour = image_array[nY][nX] #een van de naastliggende pixxels
                            diffR = np.abs(pixel[0] - neighbour[0])
                            diffB = np.abs(pixel[1] - neighbour[1])
                            diffG = np.abs(pixel[2] - neighbour[2])
                            totalDiff = np.sqrt(diffR**2 + diffB**2 + diffG**2)
                            if(totalDiff > biggestDiff):
                                biggestDiff = totalDiff
                                print(x, y, diffR, diffB, diffG, totalDiff)
                            if(totalDiff > 441):
                                output_array[nY][nX] = [255, 0, 0]
    print(biggestDiff)
    output = Image.fromarray(output_array)
    output.save('peer_output.jpg')

find_edges(peer)