Multispectral Deep Neural Network Fusion Method for Low-Light Object Detection

Despite significant strides in achieving vehicle autonomy, robust perception under low-light conditions still remains a persistent challenge. In this study, we investigate the potential of multispectral imaging, thereby leveraging deep learning models to enhance object detection performance in the context of nighttime driving. Features encoded from the red, green, and blue (RGB) visual spectrum and thermal infrared images are combined to implement a multispectral object detection model. This has proven to be more effective compared to using visual channels only, as thermal images provide complementary information when discriminating objects in low-illumination conditions. Additionally, there is a lack of studies on effectively fusing these two modalities for optimal object detection performance. In this work, we present a framework based on the Faster R-CNN architecture with a feature pyramid network. Moreover, we design various fusion approaches using concatenation and addition operators at varying stages of the network to analyze their impact on object detection performance. Our experimental results on the KAIST and FLIR datasets show that our framework outperforms the baseline experiments of the unimodal input source and the existing multispectral object detectors.