What did you do?

I'm using the ImageFilter.Kernel filter with a 3x3 kernel that should shift the image down by one pixel, but instead it is shifting the image one pixel up.

I'm assuming the order of weights in the kernel is left-right, top-bottom because, AFAIK, the documentation doesn't specify the order and I assume it uses the same ordering/coordinates as the image itself.

So, this is either a bug in the code, or a bug in the documentation.

What did you expect to happen?

The image should be shifted one pixel down.

What actually happened?

The image is shifted one pixel up.

What are your OS, Python and Pillow versions?

• OS: CentOS Linux 7.6
• Python: 3.6.7
• Pillow: 5.4.1

from PIL import Image, ImageFilter

shift_down = (
    0, 1, 0,
    0, 0, 0,
    0, 0, 0,
)

original_image = Image.open("images/example.png", mode="r")
filtered_image = original_image.filter(ImageFilter.Kernel((3, 3), shift_down))
filtered_image.save("filtered.png", format="PNG")