import cv2
import numpy as np

img = cv2.imread("2.PNG", 0)
rows = img.shape[0]
cols = img.shape[1]
shearX = np.ones((rows, cols), np.uint8)

if img is None:
    print('No image loaded')
    exit()
# Bx: x-shear parameter  Shx
Bx = 0.5
# By: y-shear parameter  Shy
By = 0.0

# Matrix factors   Chp:10 in book
a1 = 1
a2 = Bx
a3 = 0
b1 = By
b2 = 1
b3 = 0
r1 = 0
c1 = 0

# Mapping offset
maxYOffset = abs(cols * Bx)
maxXOffset = abs(rows * By)

# affine array 3x3 x-shear
affinAry = np.array(
    [[a1, a2, a3],
     [b1, b2, b3],
     [0, 0, 1]])

for r in range(0, rows):
    for c in range(0, cols):
        r1 = r + c * By - maxYOffset
        c1 = r * Bx + c - maxXOffset

        if r1 >= 0 and r1 <= rows and c1 >= 0 and c1 <= cols: # check if the point is within the boundaries
         shearX[r, c] = img[r1, c1]

print(shearX)
print(maxYOffset)
print(maxXOffset)
print(r1)
print(c1)
print(shearX)
cv2.imshow('norm', img)
cv2.imshow('shear', shearX)
cv2.waitKey(0)