#Shift all pixels left 4 spaces spaces...
#See slide number 21 from IrfanEssa-CP-02-5-Filtering.pdf

#
# Jay Summet 2024
#
#Python 3.10, OpenCV 4.5.4
#

import cv2
import numpy as np




#Load source / input image as grayscale, also works on color images...
imgIn = cv2.imread("oscar.jpg", cv2.IMREAD_GRAYSCALE)
cv2.imshow("Original", imgIn)


#Create the identity filter, but with the 1 shifted to the far right!
kernel = np.zeros( (9,9), np.float32)
kernel[4,8] = 1.0   #Identity, but shifted to far right!

print(kernel)


#cv2.BORDER_CONSTANT default to black. Without this borderType specified,
#it will default to Reflection_101
#and that makes it very hard to see the effect with only a 4 pixel shift...

custom = cv2.filter2D(imgIn, -1, kernel, borderType = cv2.BORDER_CONSTANT)
cv2.imshow("Shifted", custom)


cv2.waitKey(0)
cv2.startWindowThread()