Stabilizing Multispectral Pedestrian Detection With Evidential Hybrid Fusion

Multispectral pedestrian detection is an important task due to its critical role in a wide spectrum of applications. Basically, the complementary information from color and thermal images could provide a more accurate and reliable pedestrian detection result. However, multimodal data usually suffer from the issue of dynamic change or corruption for some modalities. At the same time, as a safety-critical task, how to produce a stable and reliable detection result is also a key challenge. To address these challenges, we propose a stable multispectral pedestrian detection (SMPD) algorithm, providing a new paradigm for multispectral detection by dynamically integrating different modalities at an evidence level. Specifically, we introduce the Dirichlet distribution to characterize the distribution of the class probabilities, parameterized with evidence from different modalities. Then, multi-branch fusion, based on Dempster-Shafer theory, can integrate these pieces of evidence to obtain the detection result. In addition, a Plug-and-Play module, termed modal enhancement module, is introduced to enhance cross-modality interaction. This is an end-to-end framework, which can induce accurate detection and uncertainty estimation, and then endows the model with both reliability and robustness against noise or corruption. Extensive experimental results demonstrate the efficiency of our algorithm compared with state-of-the-art methods.