journal article·2025-07-04Open access

AuxDepthNet: Real-Time Monocular 3D Object Detection with Depth-Sensitive Features

Ruochen Zhang, Hyeung-Sik Choi, Dongwook Jung, Phan Huy Nam Anh, Sang-Ki Jeong, Zihao Zhu

Applied Sciences· Volume 15· Issue 13

Abstract

Monocular 3D object detection is a challenging task in autonomous systems due to the lack of explicit depth information in single-view images. Existing methods often depend on external depth estimators or expensive sensors, which increase computational complexity and complicate integration into existing systems. To overcome these limitations, we propose AuxDepthNet, an efficient framework for real-time monocular 3D object detection that eliminates the reliance on external depth maps or pre-trained depth models. AuxDepthNet introduces two key components: the Auxiliary Depth Feature (ADF) module, which implicitly learns depth-sensitive features to improve spatial reasoning and computational efficiency, and the Depth Position Mapping (DPM) module, which embeds depth positional information directly into the detection process to enable accurate object localization and 3D bounding box regression. Leveraging the DepthFusion Transformer (DFT) architecture, AuxDepthNet globally integrates visual and depth-sensitive features through depth-guided interactions, ensuring robust and efficient detection. Extensive experiments on the KITTI dataset show that AuxDepthNet achieves state-of-the-art performance, with AP3D scores of 24.72% (Easy), 18.63% (Moderate), and 15.31% (Hard), and APBEV scores of 34.11% (Easy), 25.18% (Moderate), and 21.90% (Hard) at an IoU threshold of 0.7.
Source: crossref · Quality: baseline

Research context

OpenAlex topics: Advanced Neural Network Applications · Advanced Vision and Imaging · Advanced Image and Video Retrieval Techniques

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Department of Mechanical Engineering, National Korea Maritime and Ocean University, Busan 49112, Republic of Korea

Maritime ICT and Mobility Research Department, Korea Institute of Ocean Science and Technology, Busan 49111, Republic of Korea

Funding

Korea Institute of Marine Science & Technology Promotion · Ministry of Science and ICT, the Republic of Korea

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