Gabor Filter (OpenCV/Python)

gabor.py

import cv2
import numpy as np

class CvTrackbar:
    def __init__(self, name, window_name, val, max_val, callback=None):
        self.__name = name
        self.__window_name = window_name
        cv2.createTrackbar(name, window_name, val, max_val, callback or CvTrackbar.nothing)

    def value(self):
        return cv2.getTrackbarPos(self.__name, self.__window_name)

    @classmethod
    def nothing(v=None, u=None):
        pass

def create_gabor_bgr_image(gabor, size):
    gabor_image = gabor.copy()
    cv2.normalize(gabor, gabor_image, 0, 255, cv2.NORM_MINMAX)
    gabor_image = gabor_image.astype(np.uint8)
    gabor_image = cv2.cvtColor(gabor_image, cv2.COLOR_GRAY2BGR)
    gabor_image = cv2.resize(gabor_image, size)
    return gabor_image

WINDOW_TITLE = 'gabor'
GABOR_IMG_SIZE = (200, 200)
TARGET_FILENAME = 'sample.png'

img = np.zeros((1), np.uint8)
target_src = cv2.imread(TARGET_FILENAME)

cv2.namedWindow(WINDOW_TITLE)
angle_tb = CvTrackbar('angle', WINDOW_TITLE, 0, 180)

while True:
    cv2.imshow(WINDOW_TITLE, img)

    ksize = (10, 10)
    sigma = 2.0
    theta = (np.pi / 180) * angle_tb.value()
    lambd = 10
    gamma = 0.5
    gabor = cv2.getGaborKernel(ksize, sigma, theta, lambd, gamma)
    target_image = cv2.filter2D(target_src, -1, gabor)

    gabor_image = create_gabor_bgr_image(gabor, GABOR_IMG_SIZE)
    target_image = cv2.resize(target_image, None, fx=0.5, fy=0.5)
    gabor_area_image = np.zeros((target_image.shape[0], GABOR_IMG_SIZE[1], 3), np.uint8)
    gabor_area_image[:GABOR_IMG_SIZE[0], :GABOR_IMG_SIZE[1]] = gabor_image

    img = cv2.hconcat([gabor_area_image, target_image])

    k = cv2.waitKey(1) & 0xFF
    if k == 27:
        break

cv2.destroyAllWindows()

Please can you share the sample image file?