Add feather effect to non-rectangular images using python

Question

I want to apply the feather effect to the edges of images. Here is an example

It is pretty simple to do with rectangular images. But I'm not able to find a way to do that on non-rectangular images (ones with transparent background). Here is an example

I have tried various things with opencv and PIL but no luck. Please help me with this. Thanks you.

Answer 1

import numpy as np
import cv2
# import the image
input_image = cv2.imread('VagcO.png')
# get the number of rows & columns in m & n respectively 
n , m = input_image.shape[0], input_image.shape[1]
# copy the image for image processing
output = np.copy(input_image)
# loop on RGB channels
for layer in range(3):
    value = 255
    # loop for bottom of image only 15 rows pixel
    for row in reversed(range(n)[n-15:]):
        # loop for every column pixel in that row
        for column in range(m):
            # checking if every pixel is zero for usualy for background of images
            if output[row,column,0]==0 and output[row,column,1]==0 and output[row,column,2]==0:
                # skip that pixel
                continue
            # chaning the value to 255 and decrementing on every iteration
            output[row,column,layer] = value 
        value = value - 2
        
cv2.imshow('Original', input_image)
# crop the image to apply the bluring filter
cropedImage = output[n-20:, :, :]
mask = cv2.GaussianBlur(mask, (9,9), sigmaX=1, sigmaY=10, borderType = cv2.BORDER_DEFAULT)       
# remaning part of image
output = output[:n-20, : , :]
# adding both part into one image
feathredimg = np.concatenate((output, cropedImage), axis=0)
cv2.imshow("Freathred Image", feathredimg)
cv2.waitKey(0)
cv2.destroyAllWindows() 

I created the solution for the given problem. Have a look. Hope this can help. This code is working perfectly with the given example image. enter image description here