EarlyTom:早期Token压缩实现快速视频理解
阅读原文· arxiv.org视频大语言模型在视频理解中能力强,但处理海量视觉token效率低下。现有方案多在预填充后期压缩,未优化视觉编码器本身。研究指出视觉编码对时间首token(TTFT)延迟贡献大,因此压缩应提前。为此提出EarlyTom,一个免训练的压缩框架,它在视觉编码器内部执行早期视觉token压缩,并引入解耦的空间token选择策略。在单卡A100 GPU上运行LLaVA-OneVision-7B时,EarlyTom将TTFT最高降低2.65倍,FLOPs减少高达61%,同时保持与全token基线相当的准确度,提升了部署实用性。
Video large language models (Video-LLMs) have demonstrated strong capabilities in video understanding tasks. However, their practical deployment is still hindered by the inefficiency introduced by processing massive amounts of visual tokens. Although recent approaches achieve extremely low token retention ratios while maintaining accuracy comparable to full-token baselines, most of them perform compression only at the late stage of prefilling, leaving the efficiency of the vision encoder unoptimized. In this paper, we first show that vision encoding contributes a large portion to the time-to-first-token (TTFT). Therefore, instead of compressing visual tokens only after the vision encoder, performing compression inside the encoder still leaves substantial room for exploration. Based on this insight, we propose EarlyTom, a training-free token compression framework that performs early-stage visual token compression inside the vision encoder, enabling significantly better TTFT reduction and higher throughput. In addition, we introduce a decoupled spatial token selection strategy that improves the overall compression effectiveness. EarlyTom reduces TTFT by up to 2.65x and FLOPs by up to 61% on a single NVIDIA A100 GPU for the LLaVA-OneVision-7B model, while maintaining accuracy comparable to the full-token baseline. These improvements substantially enhance the practicality of deploying Video-LLMs in real-world production scenarios.