Zero-Shot Metric Depth with a Field-of-View Conditioned Diffusion Model
Saurabh Saxena, Junhwa Hur, Charles Herrmann, Deqing Sun, David J. Fleet
TL;DR
This work introduces DMD, a diffusion-based framework for zero-shot metric depth estimation that jointly models indoor and outdoor scenes without task-specific architectural biases. By representing depth in log-scale, augmenting and conditioning on field-of-view, and training on a diverse data mixture with an efficient v-parameterized denoiser, it delivers state-of-the-art REL reductions on multiple zero-shot benchmarks while maintaining fast inference. Extensive ablations demonstrate the critical roles of log-depth, FOV augmentation/conditioning, and diffusion parameterization in enabling robust cross-domain depth estimation. The approach offers a practical route to metric depth in varied environments and camera intrinsics, with potential for further improvements via intrinsic prediction and larger training corpora.
Abstract
While methods for monocular depth estimation have made significant strides on standard benchmarks, zero-shot metric depth estimation remains unsolved. Challenges include the joint modeling of indoor and outdoor scenes, which often exhibit significantly different distributions of RGB and depth, and the depth-scale ambiguity due to unknown camera intrinsics. Recent work has proposed specialized multi-head architectures for jointly modeling indoor and outdoor scenes. In contrast, we advocate a generic, task-agnostic diffusion model, with several advancements such as log-scale depth parameterization to enable joint modeling of indoor and outdoor scenes, conditioning on the field-of-view (FOV) to handle scale ambiguity and synthetically augmenting FOV during training to generalize beyond the limited camera intrinsics in training datasets. Furthermore, by employing a more diverse training mixture than is common, and an efficient diffusion parameterization, our method, DMD (Diffusion for Metric Depth) achieves a 25\% reduction in relative error (REL) on zero-shot indoor and 33\% reduction on zero-shot outdoor datasets over the current SOTA using only a small number of denoising steps. For an overview see https://diffusion-vision.github.io/dmd
