HiDrop:通过晚期注入、凹形金字塔剪枝和早期退出实现MLLM中的层次视觉令牌减少
HiDrop: Hierarchical Vision Token Reduction in MLLMs via Late Injection, Concave Pyramid Pruning, and Early Exit
AI总结:
HiDrop通过晚期注入、凹形金字塔剪枝和早期退出机制,实现多模态大语言模型中视觉令牌的高效减少,提升训练效率并保持性能。
摘要:
多模态大语言模型(MLLMs)中处理视觉令牌的二次计算成本阻碍了其广泛应用。尽管渐进式视觉令牌剪枝提供了一个有前景的解决方案,但当前方法误判了浅层层的功能并使用刚性的调度方案,无法释放全部效率潜力。为了解决这些问题,我们提出了HiDrop框架,该框架将令牌剪枝与MLLM层的真实层次功能对齐。HiDrop有两个关键创新:(1)晚期注入,通过绕过被动浅层层,在活跃融合开始的地方引入视觉令牌;(2)带有早期退出机制的凹形金字塔剪枝,以动态调整中间和深层层的剪枝率。此过程通过层间相似性度量和可微的top-k操作符进行优化。为确保实际效率,HiDrop进一步结合了持久的位置编码、与FlashAttention兼容的令牌选择以及并行解耦的视觉计算,以消除与动态令牌减少相关的隐藏开销。广泛的实验表明,HiDrop在压缩约90%的视觉令牌的同时保持原始性能,并将训练速度提升1.72倍。我们的工作不仅为高效MLLM训练和推理设定了新的最先进的标准,还为多模态融合的层次结构提供了有价值的见解。代码已发布在https://github.com/EIT-NLP/HiDrop。
英文摘要:
The quadratic computational cost of processing vision tokens in Multimodal Large Language Models (MLLMs) hinders their widespread adoption. While progressive vision token pruning offers a promising solution, current methods misinterpret shallow layer functions and use rigid schedules, which fail to unlock the full efficiency potential. To address these issues, we propose HiDrop, a framework that aligns token pruning with the true hierarchical function of MLLM layers. HiDrop features two key innovations: (1) Late Injection, which bypasses passive shallow layers to introduce visual tokens exactly where active fusion begins; and (2) Concave Pyramid Pruning with an Early Exit mechanism to dynamically adjust pruning rates across middle and deep layers. This process is optimized via an inter-layer similarity measure and a differentiable top-k operator. To ensure practical efficiency, HiDrop further incorporates persistent positional encoding, FlashAttention-compatible token selection, and parallel decoupling of vision computation to eliminate hidden overhead associated with dynamic token reduction. Extensive experiments show that HiDrop compresses about 90% visual tokens while matching the original performance and accelerating training by 1.72 times. Our work not only sets a new state-of-the-art for efficient MLLM training and inference but also provides valuable insights into the hierarchical nature of multimodal fusion. The code is released at https://github.com/EIT-NLP/HiDrop.
机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。