Push preden use sfukam

assignment2/solution.py

@@ -1,7 +1,6 @@
 import numpy as np
 import numpy.typing as npt
 from matplotlib import pyplot as plt
-import random
 import cv2
 import uz_framework.image as uz_image
 import uz_framework.text as uz_text
@@ -278,6 +277,79 @@ def two_e():
 ################################
 # EXCERCISE 3: Image Filtering #
 ################################
+def ex3():
+    #three_a()
+    three_b()
+
+def three_a():
+    """
+    Write a function gaussfilter that generates a Gaussian filter and applies it to a
+    2-D image. You can use the function cv2.filter2D() to perform the convolution
+    using the desired kernel. Generate a 1-D Gaussian kernel and first use it to filter
+    the image along the first dimension, then convolve the result using the same kernel,
+    but transposed.
+    Hint: Numpy arrays have an attribute named T, which is used to access the transpose
+    of the array, e.g. k_transposed = k.T.
+    Test the function by loading the image lena.png and converting it to grayscale.
+    Then, corrupt the image with Gaussian noise (every pixel value is offset by a random number 
+    sampled from the Gaussian distribution) and separately with saltand-pepper noise. 
+    You can use the functions gauss_noise and sp_noise that are
+    included with the instructions (a2_utils.py). Use the function gaussfilter to try
+    and remove noise from both images
+    """
+    lena = uz_image.imread('./data/images/lena.png', uz_image.ImageType.float64)
+    lena_grayscale = uz_image.transform_coloured_image_to_grayscale(lena.astype(np.float64))
+    lena_gausssian_noise = uz_image.gauss_noise(lena_grayscale)
+    lena_salt_and_pepper = uz_image.sp_noise(lena_grayscale)
+    kernel = uz_image.get_gaussian_kernel(1)
+
+    # Denoised
+    denosised_lena = cv2.filter2D(lena_gausssian_noise, cv2.CV_64F, kernel)
+    denosised_lena = cv2.filter2D(denosised_lena, cv2.CV_64F, kernel.T)
+    # Desalted
+    desalted_lena = cv2.filter2D(lena_salt_and_pepper, cv2.CV_64F, kernel)
+    desalted_lena = cv2.filter2D(desalted_lena, cv2.CV_64F, kernel.T)
+
+    fig, axs = plt.subplots(2, 3)
+    
+    axs[0, 0].imshow(lena_grayscale, cmap='gray')
+    axs[0, 0].set(title='Orginal image')
+    axs[0, 1].imshow(lena_gausssian_noise, cmap='gray')
+    axs[0, 1].set(title='Gaussian noise')
+    axs[1, 1].imshow(denosised_lena, cmap='gray')
+    axs[1, 1].set(title='Denoised lena')
+    axs[0, 2].imshow(lena_salt_and_pepper, cmap='gray')
+    axs[0, 2].set(title='Salt and Pepper')
+    axs[1, 2].imshow(desalted_lena, cmap='gray')
+    axs[1, 2].set(title='Desalted lena')
+    
+    plt.show()
+
+def three_b():
+    """
+    Convolution can also be used for image sharpening. Look at its definition in the
+    lecture slides and implement it. Test it on the image from file museum.jpg.
+    """
+    museum_grayscale = cv2.imread('./data/images/museum.jpg', 0)
+
+    #https://blog.demofox.org/2022/02/26/image-sharpening-convolution-kernels/
+    # Pa tui na slajdih lepo pise
+
+    kernel = np.array([[-1, -1, -1], 
+                       [-1, 17, -1],
+                       [-1, -1,-1]])
+    kernel = kernel * 1./9.
+
+    museo = cv2.filter2D(museum_grayscale, cv2.CV_64F, kernel)
+    museo = cv2.filter2D(museo, cv2.CV_64F, kernel.T)
+
+    fig, axs = plt.subplots(1, 2)
+    axs[0].imshow(museum_grayscale, cmap='gray')
+    axs[0].set(title='Original')
+    axs[1].imshow(museo, cmap='gray')
+    axs[1].set(title='Sharpened')
+    plt.savefig('.')
+    plt.show()
     
 
 # ######## #
@@ -286,7 +358,8 @@ def two_e():
 
 def main():
     #ex1()
-    ex2()
+    #ex2()
+    ex3()
 
 if __name__ == '__main__':
     main()

assignment2/uz_framework/image.py

@@ -290,9 +290,16 @@ def get_gaussian_kernel(sigma: float):
 
     return result / np.sum(result)
 
+def gaussfilter2D(imge: Union[npt.NDArray[np.float64], npt.NDArray[np.uint8]], sigma: float):
+    kernel = get_gaussian_kernel(sigma)
+    kernel = cv2.filter2D(kernel, cv2.CV_64F, kernel)
+
+    
+
 def gauss_noise(I, magnitude=.1):
     # input: image, magnitude of noise
     # output: modified image
+    I = I.copy()
 
     return I + np.random.normal(size=I.shape) * magnitude