problem adding two numpy arrays

[djf123]

I am trying to do the following. I want to add the Mona Lisa .jpg image at this link to a slightly larger numpy array of all zeroes (called base_image1) of size (605,405,4). Alpha channel values was first added to the Mona Lisa image and converted to a numpy array (called image1) of size (599,402,4).

Next, I add the smaller Mona Lisa image to a location within the larger numpy array of all zeroes. Finally I display the resulting image.

What I was expecting to get displayed was an image of the Mona Lisa with a little bit of white border in certain regions. Instead it simply displays a (605,405,4) image that looks completely white everywhere! Why is this happening? I can't understand why this is occuring . Below is my code:

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import numpy as np from PIL import Image   #Load Mona Lisa image and Add fully opaque alpha channel values path='C:\\Users\\john\\Desktop\\monalisa.jpg' image = Image.open(path) image.putalpha(255)   #Make larger numpy array of all zeroes base_image1=np.zeros((605, 405, 4),dtype=int)   #Convert Mona Lisa image to numpy array and add Mona Lisa array to region within larger array width, height = image.size image1=np.array(image) x=0 y=0 base_image1[x:(x+height),y:(y+width),:]=base_image1[x:(x+height),y:(y+width),:]+image1   #Display image img = Image.fromarray(base_image1, 'RGBA') img.show()

[Addweb]

import numpy as np

[deanhystad]

The problem is not adding the arrays, the problem is that one of the arrays has the wrong dtype. The dtype for base_image1 should be np.int8. You could have determined this by looking at the dtype for image1, or just use dtype from image1.

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image = Image.open(path) image.putalpha(255) image1 = np.array(image)   # Make larger numpy array of all zeroes base_image1 = np.zeros((605, 405, 4), dtype=image1.dtype)

You can copy image1 into base_image1 without the extra addition step.

1	base_image1[x:(x+height),y:(y+width),:] = image1