HiPrune: Hierarchical Attention for Efficient Token Pruning in Vision-Language Models

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Liu, Jizhihui, Du, Feiyi, Zhu, Guangdao, Lian, Niu, Li, Jun, Chen, Bin, Guan, Weili, Wang, Yaowei
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866918453639643136
author Liu, Jizhihui
Du, Feiyi
Zhu, Guangdao
Lian, Niu
Li, Jun
Chen, Bin
Guan, Weili
Wang, Yaowei
author_facet Liu, Jizhihui
Du, Feiyi
Zhu, Guangdao
Lian, Niu
Li, Jun
Chen, Bin
Guan, Weili
Wang, Yaowei
contents Vision-Language Models (VLMs) encode images and videos into abundant tokens, which contain substantial redundancy and computation cost. While visual token pruning mitigates the issue, most existing methods lack insight into the intrinsic property of the vision encoder itself. In this work, we dive into the vision encoder and prove that the middle layers pay more attention to the main objects of the image qualitatively and quantitatively, while the deep layers to tokens with rich global information. Utilizing this Hierarchical attention pattern, we propose HiPrune, a training-free and model-agnostic token Pruning method. HiPrune identifies three types of visual tokens according to their attention in different phases of the vision encoder, which preserves different levels of information. By coupling with the similarity of text tokens, we propose a prompt-aware variance, HiPrune++, which further improves instruction following performance under a very low token budget. Extensive experiments across four representative VLMs show that HiPrune achieves up to 99.3% of task accuracy with only 1/3 of the tokens, while reducing inference FLOPs by 58.7%. HiPrune++ maintains up to 99.7% accuracy with 2/9 tokens, highlighting robustness under high-resolution. Our code is available at https://github.com/Danielement321/HiPrune.
format Preprint
id arxiv_https___arxiv_org_abs_2508_00553
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle HiPrune: Hierarchical Attention for Efficient Token Pruning in Vision-Language Models
Liu, Jizhihui
Du, Feiyi
Zhu, Guangdao
Lian, Niu
Li, Jun
Chen, Bin
Guan, Weili
Wang, Yaowei
Computer Vision and Pattern Recognition
Vision-Language Models (VLMs) encode images and videos into abundant tokens, which contain substantial redundancy and computation cost. While visual token pruning mitigates the issue, most existing methods lack insight into the intrinsic property of the vision encoder itself. In this work, we dive into the vision encoder and prove that the middle layers pay more attention to the main objects of the image qualitatively and quantitatively, while the deep layers to tokens with rich global information. Utilizing this Hierarchical attention pattern, we propose HiPrune, a training-free and model-agnostic token Pruning method. HiPrune identifies three types of visual tokens according to their attention in different phases of the vision encoder, which preserves different levels of information. By coupling with the similarity of text tokens, we propose a prompt-aware variance, HiPrune++, which further improves instruction following performance under a very low token budget. Extensive experiments across four representative VLMs show that HiPrune achieves up to 99.3% of task accuracy with only 1/3 of the tokens, while reducing inference FLOPs by 58.7%. HiPrune++ maintains up to 99.7% accuracy with 2/9 tokens, highlighting robustness under high-resolution. Our code is available at https://github.com/Danielement321/HiPrune.
title HiPrune: Hierarchical Attention for Efficient Token Pruning in Vision-Language Models
topic Computer Vision and Pattern Recognition
url https://arxiv.org/abs/2508.00553