OpenCV with Python By Example

Creating a vignette filter

Using all the information we have, let's see if we can create a nice vignette filter. The output will look something like the following:

Here is the code to achieve this effect:

import cv2 import numpy as np img = cv2.imread('input.jpg') rows, cols = img.shape[:2] # generating vignette mask using Gaussian kernels kernel_x = cv2.getGaussianKernel(cols,200) kernel_y = cv2.getGaussianKernel(rows,200) kernel = kernel_y * kernel_x.T mask = 255 * kernel / np.linalg.norm(kernel) output = np.copy(img) # applying the mask to each channel in the input image for i in range(3): output[:,:,i] = output[:,:,i] * mask cv2.imshow('Original', ...