Survey on Image and Point-Cloud Fusion-Based Object Detection in Autonomous Vehicles

With the improvements in sensor performance (cameras, Lidars) and the application of deep learning in object detection, autonomous vehicles (AVs) are gradually becoming more notable. After 2019, AV has produced a wave of enthusiasm, and many papers on object detection were published, boasting both practicality and innovation. Due to hardware limitations, it is difficult to accomplish accurate and reliable environment perception using a single sensor. However, multi-sensor fusion technology provides an acceptable solution. Considering the AV cost and object detection accuracy, both the traditional and existing literature on object detection using image and point-cloud was reviewed in this paper. Additionally, for the fusion-based structure, the object detection method was categorized in this paper based on the image and point-cloud fusion types: early fusion, deep fusion, and late fusion. Moreover, a clear explanation of these categories was provided including both the advantages and limitations. Finally, the opportunities and challenges the environment perception may face in the future were assessed.