Diffusion Illusions: Hiding Images in Plain Sight

We explore the problem of computationally generating special images that produce multi-arrangement optical illusions when physically arranged and viewed in a certain way, which we call 'prime' images. First, we propose a formal definition for this problem. Next, we introduce Diffusion Illusions, the first comprehensive pipeline designed to automatically generate a wide range of these multi-arrangement illusions. Specifically, we both adapt the existing 'score distillation loss' and propose a new 'dream target loss' to optimize a group of differentially parametrized prime images, using a frozen text-to-image diffusion model. We study three types of illusions, each where the prime images are arranged in different ways and optimized using the aforementioned losses such that images derived from them align with user-chosen text prompts or images. We conduct comprehensive experiments on these illusions and verify the effectiveness of our proposed method qualitatively and quantitatively. Additionally, we showcase the successful physical fabrication of our illusions - as they are all designed to work in the real world.