  We investigate the potential of learning visual representations using
synthetic images generated by text-to-image models. This is a natural question
in the light of the excellent performance of such models in generating
high-quality images. We consider specifically the Stable Diffusion, one of the
leading open source text-to-image models. We show that (1) when the generative
model is configured with proper classifier-free guidance scale, training
self-supervised methods on synthetic images can match or beat the real image
counterpart; (2) by treating the multiple images generated from the same text
prompt as positives for each other, we develop a multi-positive contrastive
learning method, which we call StableRep. With solely synthetic images, the
representations learned by StableRep surpass the performance of representations
learned by SimCLR and CLIP using the same set of text prompts and corresponding
real images, on large scale datasets. When we further add language supervision,
StableRep trained with 20M synthetic images achieves better accuracy than CLIP
trained with 50M real images.
