So, this is surprising. Apparently there’s more cause, effect, and sequencing in diffusion models than what I expected, which would be roughly ‘none’. Google here uses SD 1.4, as the core of the diffusion model, which is a nice reminder that open models are useful to even giant cloud monopolies. The two main things of note I took away from the summary were: 1) they got infinite training data using agents playing doom…
Just want to clarify a couple possible misconceptions: The diffusion model doesn’t maintain any state itself, though its weights may encode some notion of cause/effect. It just renders one frame at a time (after all it’s a text to image model, not text to video). Instead of text, the previous states and frames are provided as inputs to the model to predict the next frame. Noise is added to the previous frames before…
The training was over almost 1 billion frames, 20 days of full-time play-time, taking a screenshot of every single inch of the map.
Now you show him N frames as input, and ask it "give me frame N+1", then it gives you the frame n. N+1 back based on how it was originally seen during training.
But it is not frame N+1 from a mysterious intelligence, it's simply frame N+1 given back from past database.
The drift you mentioned is actually a clear (but sad) proof that the model does not work at inventing new frames, and can only spit out an answer from the past dataset.
It's a bit like if you train stable diffusion on Simpsons episodes, and that it outputs the next frame of an existing episode that was in the training set, but few frames later goes wild and buggy.