OGDepth: Leveraging Object Guidance in Diffusion Models for Enhanced Monocular Depth Estimation

Monocular depth estimation stands as a fundamental pursuit in computer vision. Recently, some methods have attempted to introduce the text-to-image diffusion model into the domain of monocular depth estimation and achieved impressive results. However, these methods typically employ pre-defined templates as text prompts to guide the learning of denoising networks, resulting in limited flexibility and scalability. In this paper, we propose OGDepth, a diffusion-based monocular depth estimation network with object prompts generated by taking advantage of the object detection information from the scene. Specifically, we design an Object Prompt Module (OPM) to encode the object detection information into prompts that are more closely aligned with the image content, offering richer contextual information while circumventing the monotony and redundancy inherent in template-generated prompts. Moreover, we employ bounding box information for each object to filter and localize objects, enabling the model to grasp relative positional information within the scene. This facilitates the creation of a more precise depth map. Additionally, we design a Global-Local Interaction Decoder (GLID) to facilitate the mutual exchange of features at different scales, enabling efficient feature fusion. Our approach underwent rigorous experiments across multiple datasets, with results showcasing its state-of-the-art performance. Notably, on the KITTI dataset, our model achieves an RMSE of 1.967 and a REL of 0.047, and both metrics are the best among all compared methods. On the NYU Depth V2 dataset, our method achieves an RMSE score of 0.221, representing a notable 12.9% enhancement compared to the baseline method (VPD).