easter egg :)

if you use the following pattern:
[

[0.5, 0.5, 0.5],
[0.5, -5, 0.5],
[0.5, 0.5, 0.5],

]

and make sure that instead of red, you place black, it would give you the outline of the image.

if you use the following one:
[

[1, 1, 1],
[0, 0, 0],
[-1, -1, -1],

]

this would give you a vertical edge detection instead of a horizontal one.