ST-Pruner picked visual tokens with spectral saliency before the LLM ever saw them, keeping 95 percent of full-token performance on 11.1 percent of the tokens
AspireAI community · arXiv (WACV 2027)
Vision-language models pay heavily for long visual-token sequences, and pruning them is delicate because the signal available early is weaker than the query-conditioned signal that only appears deep inside the LLM. ST-Pruner shows you do not have to wait for it: it fuses attention-independent spectral saliency with inverted patch-text similarity through parameter-free multiplicative fusion, selecting tokens before the LLM is consulted. Across diverse LVLMs it retained over 95% of full-token performance using at most 11.1% of visual tokens, with a 3.2x end-to-end speedup on LLaVA-NeXT. It is training-free and was accepted to WACV 2027, though the 11.1% is a ceiling rather than an average budget and the headline speedup is measured on LLaVA-NeXT.
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