a3g3.py

import cv2
import matplotlib.pyplot as plt
import numpy as np

path = '/Users/agnesmustar/data/random_images/cars.jpg'
im = cv2.resize(cv2.imread(path, cv2.IMREAD_GRAYSCALE), (500, 300))

def convolutional_layer(im, W):
    m = im.shape[0] - 2
    n = im.shape[1] - 2
    transformed_image = np.zeros((m,n))

    for i in range(m):
      for j in range(n):
        patch = im[i:i+3, j:j+3]
        transformed_image[i,j] = np.multiply(patch, W).sum()
    return transformed_image
  
W = np.array([[-2,-2,-2],[-2,10,-2],[-2,-2,-2]])
transformed_image = convolutional_layer(im, W)
plt.imshow(transformed_image, cmap='gray')
plt.show()