STARFlow2 builds upon the Pretzel architecture, vertically interleaving a frozen pretrained VLM stream with a TARFlow stream via residual skip connections. This design preserves pretrained multimodal understanding, enables high-fidelity continuous image generation, and achieves structural unification under a single causal mechanism. Combined with a deep-shallow flow design and a unified FAE latent space, STARFlow2 supports cache-friendly interleaved generation where both text and visual outputs directly enter the KV-cache without re-encoding.
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