ViQ:任意分辨率的文本对齐视觉量化表示
ViQ: Text-Aligned Visual Quantized Representations at Any Resolution
摘要
对文本和视觉信息进行统一的表示方式是一种自然的追求,因为这种方式能够简化多模态建模过程,同时提升训练效率。然而,将图像以与文本相同的离散信号形式来表示,必然会导致严重的信息损失。现有的研究在离散表示中平衡低层次细节与高层次语义方面存在困难:以重建为导向的表示通常缺乏语义信息,而具有更强语义特征的表示则往往会出现细节丢失的问题。我们提出了ViQ这一视觉量化表示框架,该框架旨在在离散表示中平衡语义与细节,同时支持以原始分辨率输入数据,从而能够作为任意视觉数据的统一通用离散表示方式。我们的方法将量化学习过程分为两个阶段:与文本相关的预训练和特征离散化过程。通过与文本相关的预训练,我们可以利用预训练的语言模型提供的丰富语义信息来优化视觉编码器,使其能够处理以原始分辨率输入的视觉数据。在特征离散化过程中,我们采用了一种渐进式特征空间压缩策略,以及一种基于位置的逐层量化机制,从而能够灵活处理不同分辨率的数据。在多种多模态任务中的实验表明,ViQ在具有连续且高维视觉特征的多模态视觉编码器中能够取得与最先进模型相当的性能,同时还能保持较低的重建误差。此外,使用视觉量化表示进行多模态训练可以显著提高效率,对于不同的基础LLM和训练方法,效率可提升20%到70%。
English Abstract
A unified representation for text and vision is a natural pursuit, as it enables simpler multimodal modeling and more efficient training. However, representing images as discrete signals in the same way as text inevitably introduces severe information loss. Existing work struggles to balance low-level details and high-level semantics in discrete representations: reconstruction-oriented representations often lack semantic information, whereas semantically stronger features typically suffer from severe loss of detail. We present ViQ, a Visual Quantized Representations framework, which is designed to balance semantics and details in discrete representations while supporting inputs at native resolutions, thereby enabling it to serve as a unified and general discrete representation for arbitrary visual inputs. Our approach structures quantization learning into two stages: text-aligned pre-training and feature discretization. With text-aligned pre-training, we enhance the visual encoder semantic-rich supervision from the pretrained language model and enable it to process native-resolution visual inputs. During discretization, we propose a proximal representation learning strategy to progressively compact the feature space, along with a position-aware head-wise quantization mechanism that enables flexible processing of arbitrary resolutions. Extensive experiments on multimodal tasks demonstrate that ViQ achieves competitive performance compared to state-of-the-art multimodal vision encoders with continuous and high-dimensional visual features, while maintaining high precision in low-level reconstruction. We also show that multimodal training with visual quantized representations largely improves efficiency, yielding up to 20\%-70\% acceleration with different base LLMs and training recipes.