A zooming or scaling algorithm that only uses available image data is deterministic, it should get the same result every time.
One that relies on a neural network trained on other images is not, it might produce a subtly different image each time it's run and introduce artefacts from other images.
One that relies on a neural network trained on other images is not, it might produce a subtly different image each time it's run and introduce artefacts from other images.