Rethinking Iterative Stereo Matching from Diffusion Bridge Model Perspective
Yuguang Shi
TL;DR
The paper addresses limitations of RNN-based iterative stereo matching, where discrete updates can degrade local detail. It reframes iterative optimization as a diffusion-model task (DMIO), introducing a bridge diffusion disparity optimization, a Time-based Gated Recurrent Unit (T-GRU), and an attention-based context network with Agent Attention to preserve high-frequency information. Empirical results on Scene Flow, KITTI, and zero-shot tests demonstrate state-of-the-art or competitive performance, with 8 iterations sufficing to achieve strong results. The work advances diffusion-inspired, iterative stereo methods, offering improved edge fidelity and cross-domain robustness while acknowledging computational costs and the need for dense ground truth.
Abstract
Recently, iteration-based stereo matching has shown great potential. However, these models optimize the disparity map using RNN variants. The discrete optimization process poses a challenge of information loss, which restricts the level of detail that can be expressed in the generated disparity map. In order to address these issues, we propose a novel training approach that incorporates diffusion models into the iterative optimization process. We designed a Time-based Gated Recurrent Unit (T-GRU) to correlate temporal and disparity outputs. Unlike standard recurrent units, we employ Agent Attention to generate more expressive features. We also designed an attention-based context network to capture a large amount of contextual information. Experiments on several public benchmarks show that we have achieved competitive stereo matching performance. Our model ranks first in the Scene Flow dataset, achieving over a 7% improvement compared to competing methods, and requires only 8 iterations to achieve state-of-the-art results.
