MixerFlow for Image Modelling
Eshant English Matthias Kirchler Christoph Lippert
Normalising flows are statistical models that transform a complex density
into a simpler density through the use of bijective transformations enabling
both density estimation and data generation from a single model. In the context
of image modelling, the predominant choice has been the Glow-based
architecture, whereas alternative architectures remain largely unexplored in
the research community. In this work, we propose a novel architecture called
MixerFlow, based on the MLP-Mixer architecture, further unifying the generative
and discriminative modelling architectures. MixerFlow offers an effective
mechanism for weight sharing for flow-based models. Our results demonstrate
better density estimation on image datasets under a fixed computational budget
and scales well as the image resolution increases, making MixeFlow a powerful
yet simple alternative to the Glow-based architectures. We also show that
MixerFlow provides more informative embeddings than Glow-based architectures.