ValueError: could not broadcast input array from shape (75) into shape (25)

[route2sabya]

I am a Python beginner. I am trying to follow the tutorial posted here about change detection for satellite images.

I am receiving a value error. Can anyone guide me towards resolving the issue.

import cv2
import numpy as np
from sklearn.cluster import KMeans
from sklearn.decomposition import PCA
from collections import Counter
from scipy.misc import imread, imresize, imsave

def find_vector_set(diff_image, new_size):
   
    i = 0
    j = 0
    vector_set = np.zeros(((int(new_size[0]) * int(new_size[1])) // 25, 25))
    while i < vector_set.shape[0]:
        while j < new_size[0]:
            k = 0
            while k < new_size[1]:
                block   = diff_image[j:j+5, k:k+5]
                feature = block.ravel()
                vector_set[i, :] = feature
                k = k + 5
            j = j + 5
        i = i + 1
        
    print ('vector_set shape', vector_set.shape)
            
    mean_vec   = np.mean(vector_set, axis = 0)    
    vector_set = vector_set - mean_vec
    
    return vector_set, mean_vec
    
  
def find_FVS(EVS, diff_image, mean_vec, new):
    
    i = 2 
    feature_vector_set = []
    
    while i < new[0] - 2:
        j = 2
        while j < new[1] - 2:
            block = diff_image[i-2:i+3, j-2:j+3]
            feature = block.flatten()
            feature_vector_set.append(feature)
            j = j+1
        i = i+1
        
    FVS = np.dot(feature_vector_set, EVS)
    FVS = FVS - mean_vec
    print ("feature vector space size", FVS.shape)
    return FVS

def clustering(FVS, components, new):
    
    kmeans = KMeans(components, verbose = 0)
    kmeans.fit(FVS)
    output = kmeans.predict(FVS)
    count  = Counter(output)

    least_index = min(count, key = count.get)            
    change_map  = np.reshape(output,(new[0] - 4, new[1] - 4))
    
    return least_index, change_map

   
def find_PCAKmeans(imagepath1, imagepath2):
    
    print ('Operating')
    
    image1 = imread(imagepath1)
    image2 = imread(imagepath2)
    
    new_size = np.asarray(image1.shape) // 25
    image1 = imresize(image1, (new_size)).astype(np.int16)
    image2 = imresize(image2, (new_size)).astype(np.int16)
    
    diff_image = abs(image1 - image2)   
    imsave('diff.jpg', diff_image)
    print ('Both images resized to ',new_size)
        
    vector_set, mean_vec = find_vector_set(diff_image, new_size)
    
    pca     = PCA()
    pca.fit(vector_set)
    EVS = pca.components_
        
    FVS     = find_FVS(EVS, diff_image, mean_vec, new_size)
    
    print ('computing k means')
    
    components = 3
    least_index, change_map = clustering(FVS, components, new_size)
    
    change_map[change_map == least_index] = 255
    change_map[change_map != 255] = 0
    
    change_map = change_map.astype(np.uint8)
    kernel     = np.asarray(((0,0,1,0,0),
                             (0,1,1,1,0),
                             (1,1,1,1,1),
                             (0,1,1,1,0),
                             (0,0,1,0,0)), dtype=np.uint8)
    cleanChangeMap = cv2.erode(change_map,kernel)
    imsave("changemap.jpg", change_map)
    imsave("cleanchangemap.jpg", cleanChangeMap)

    
if __name__ == "__main__":
    a = 'Argentina_01131994_md.jpg'
    b = 'Argentina_01202014_md.jpg'
    find_PCAKmeans(a,b)    
    

OUTPUT :
File "D:/Numer8/change_detection4.py", line 26, in find_vector_set
vector_set[i, :] = feature

ValueError: could not broadcast input array from shape (75) into shape (25)