Lens Blur effect using Python Pillow

Question

In Pillow, we can blur image using filters:

blurred_image = original_image.filter(ImageFilter.BLUR)

But this is not a true lens effect. Is it possible using some custom filter? Any example?

(Number 2 is what I need. Number 3 is what pillow BLUR filter.)

Answer 1

In Pillow, we can blur image using filters:

blurred_image = original_image.filter(ImageFilter.BLUR)

But this is not a true lens effect. Is it possible using some custom filter? Any example?

(Number 2 is what I need. Number 3 is what pillow BLUR filter.)

Answer 2

In Pillow, we can blur image using filters:

blurred_image = original_image.filter(ImageFilter.BLUR)

But this is not a true lens effect. Is it possible using some custom filter? Any example?

(Number 2 is what I need. Number 3 is what pillow BLUR filter.)

Answer 3

I tried to convert above pseudo-code into real code but not getting desired result. any idea on where I am doing wrong ?

import cv2
import numpy as np
 
def gammaCorrection(src, gamma):
    invGamma = 1 / gamma 
    table = [((i / 255) ** invGamma) * 255 for i in range(256)]
    table = np.array(table, np.uint8) 
    return cv2.LUT(src, table)     
 
image = cv2.imread(r'C:\Users\test\Desktop\test.jpg')
gammaCorrectedImage = gammaCorrection(image, 3.0)   #Or whatever power works for you
ksize = (40, 40)
bokeh = cv2.blur(gammaCorrectedImage, ksize)        #discBlur(gammaCorrectedImage)
bokeh = gammaCorrection(bokeh, 0.33)                #To get back the original gamma.
blurImage = cv2.blur(image, ksize)                  #discBlur(image)
finalImage = cv2.max(bokeh, blurImage)