Using Pillow to find DPI

Question

I'm trying to find out the DPI of an image using the Pillow module.

I'm doing this

image = Image.open("image.jpeg")
print(image.info["dpi"])

which returns

(300, 300)

Why is this a tuple? I was expecting a single value. What do the two values relate to and which should I use to give me the same value I see in photoshop?

Answer 1

The docs do not say much about this, but I've gone roughly through source code and it seems that this refers to DPI in x and y axis (look at search results)

Especially this suggests that there could exist something as non-square pixels.