A 6.1M-parameter encoder–decoder, distilled at scale from a foundation model, exported without graph surgery to GPUs, CPUs, and mobile NPUs alike.
Poster will go live before the conference.
Depth from a single image in real time, directly on device — no connection, no setup, no restrictions on scene type. Captured live on an iPhone 12.
Abstract
Monocular depth estimation has seen remarkable progress through foundation models achieving robust zero-shot generalization, yet their computational demands place them far beyond the reach of embedded and mobile platforms.
Lightweight alternatives exist, but have been developed almost exclusively within single-domain, self-supervised paradigms, failing silently under domain shift. We present ZipDepth, a compact monocular depth network that bridges this gap by combining an efficient reparameterizable encoder–decoder with large-scale knowledge distillation from a foundation model over a large multi-domain training set.
Comprising just 6.1M parameters, ZipDepth runs at real-time rates from server GPUs to power-constrained devices, achieving the best trade-off between zero-shot accuracy and deployment efficiency among lightweight models across five benchmarks, taking a significant step towards the accuracy of foundation models with 50× more parameters.
Efficiency
Mean AbsRel vs. energy per frame on NVIDIA Jetson Orin NX (15 W); bubble size encodes FPS. All measurements at 384×384 resolution, vanilla FP32 without optimizations, for a clean, reproducible baseline. For the full latency/FPS comparison across backends and platforms, see Deployment and the supplementary material.
Method
Given an RGB image, ZipDepth produces a full-resolution affine-invariant inverse-depth map through a four-stage hierarchical encoder built on reparameterizable convolutional blocks — fused into plain convolutions at inference, with zero custom operators — and a streamlined decoder with hardware-adaptive convex upsampling that preserves depth boundaries at full resolution. After Conv–BN fusion, the network totals just 6.1M parameters.
Fig. 3
Four stages at strides {4, 8, 16, 32}. Dilated depthwise context and strip-pooling attention at Stage 2; SE and global-context attention at Stage 3; SPPF with bidirectional cross-scale refinement.
Coarse-to-fine fusion via grouped 1×1 convolutions down to stride 4, plus a dedicated half-resolution skip from the split stem that recovers fine spatial detail.
Two interchangeable full-resolution paths chosen before training: convex upsampling for GPU/TensorRT, and a learned nearest–bilinear blend for mobile NPU/DSP.
Training follows the scale-and-shift-invariant objective of MiDaS / Depth Anything v2, distilled from Depth Anything v2-Large over 14.1M images spanning 17 heterogeneous domains — trained end-to-end on just two NVIDIA RTX 3090 GPUs over three days.
Results
We compare against large pretrained foundation models and lightweight architectures retrained on the same multi-domain training set, on NYUv2, KITTI, ETH3D, ScanNet, and DIODE.
Among lightweight models, ZipDepth ranks first or second on every benchmark, with the best AbsRel on NYUv2 (8.4) and ScanNet (8.8). At 6.1M parameters and 3.0 GFLOPs, it reaches 34.4 FPS at ~397 mJ/frame on a 15 W Jetson Orin NX.
RGBDepth
RGBDepth
RGBDepth
RGBDepth
Drag the handle on any panel (or focus it and use ← →) to reveal ZipDepth's prediction beneath the input. Zero-shot, captured live on iPhone 12.
Deployment
Best result per platform at 384×384, median latency over 200 forward passes. Full backend-by-backend breakdown is in the supplementary material.
Speedup is measured against each device's own eager/FP32 baseline, not against the teacher model. On Intel i7, the NPU-friendly ONNX path (44.6 FPS) trails plain PyTorch JIT (48.9 FPS) — included as reported, not cherry-picked.
Citation
@inproceedings{tosi2026zipdepth,
title = {{ZipDepth}: Bringing Lightweight Zero-Shot Monocular Depth Anywhere, on Any Device},
author = {Tosi, Fabio and Bartolomei, Luca and Poggi, Matteo and Mattoccia, Stefano},
booktitle = {European Conference on Computer Vision (ECCV)},
year = {2026}
}