A diffusion vision-language model that reused certified predictions kept 99.6 percent of LLaDA-V's score at 35.3 percent of the decoding FLOPs
AspireAI community · arXiv
Diffusion vision-language models re-encode the whole image at every denoising step, and visual tokens make up 89 to 97 percent of that input on the benchmarks studied here. LOWN first measures how often the image actually matters by comparing LLaDA-V's predictions with and without it at each step: removing the image changes the token being unmasked at only 22.8 percent of steps on average, and at as few as 7.9 percent. It then predicts masked tokens without the image and processes the image only when that prediction disagrees with the last image-conditioned one, treating the agreement as a certificate. Without any training or tuned threshold it retains 99.6 percent of LLaDA-V's score on ten benchmarks at 35.3 percent of the decoding FLOPs on average, and it composes with visual token pruning. The limit: the measured need for the image differs across benchmarks, which is exactly why the method has to decide per step rather than follow a fixed schedule.
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