LIX: Implicitly Infusing Spatial Geometric
Prior Knowledge into Visual Semantic Segmentation
for Autonomous Driving
Sicen Guo
Ziwei Long
Zhiyuan Wu
Qijun Chen
Ioannis Pitas
Rui Fan
[Supplementary Material]
[Paper]
[GitHub]

Abstract

Despite the impressive performance achieved by data-fusion networks with duplex encoders for visual semantic segmentation, they become ineffective when spatial geometric data are not available. Implicitly infusing the spatial geometric prior knowledge acquired by a data-fusion teacher network into a single-modal student network is a practical, albeit less explored research avenue. This article delves into this topic and resorts to knowledge distillation approaches to address this problem. We introduce the Learning to Infuse "X" (LIX) framework, with novel contributions in both logit distillation and feature distillation aspects. We present a mathematical proof that underscores the limitation of using a single, fixed weight in decoupled knowledge distillation and introduce a logit-wise dynamic weight controller as a solution to this issue. Furthermore, we develop an adaptively-recalibrated feature distillation algorithm, including two novel techniques: feature recalibration via kernel regression and feature consistency quantification via centered kernel alignment. Extensive experiments conducted with intermediate-fusion and late-fusion networks across various public datasets provide both quantitative and qualitative evaluations, demonstrating the superior performance of our LIX framework when compared to other state-of-the-art approaches.


Acknowledgements

This research was supported by the National Natural Science Foundation of China under Grant 62473288, the National Key Laboratory of Human-Machine Hybrid Augmented Intelligence, Xi'an Jiaotong University (No. HMHAI-202406), the Fundamental Research Funds for the Central Universities, NIO University Programme (NIO UP), and the Xiaomi Young Talents Program. The research leading to these results has also received partial funding from the European Commission - European Union (under HORIZON EUROPE (HORIZON Research and Innovation Actions) under grant agreement 101093003 (TEMA) HORIZON-CL4-2022-DATA-01-01). Views and opinions expressed are, however, those of the authors only and do not necessarily reflect those of the European Union - European Commission. Neither the European Commission nor the European Union can be held responsible for them.