  Multimodal Variational Autoencoders (VAEs) represent a promising group of
generative models that facilitate the construction of a tractable posterior
within the latent space, given multiple modalities. Daunhawer et al. (2022)
demonstrate that as the number of modalities increases, the generative quality
of each modality declines. In this study, we explore an alternative approach to
enhance the generative performance of multimodal VAEs by jointly modeling the
latent space of unimodal VAEs using score-based models (SBMs). The role of the
SBM is to enforce multimodal coherence by learning the correlation among the
latent variables. Consequently, our model combines the superior generative
quality of unimodal VAEs with coherent integration across different modalities.
