stereodemo

Small Python utility to compare and visualize the output of various stereo depth estimation algorithms:

• Make it easy to get a qualitative evaluation of several state-of-the-art models in the wild
• Feed it left/right images or capture live from an OAK-D camera
• Interactive colored point-cloud view since nice-looking disparity images can be misleading
• Try different parameters on the same image

Included methods (implementation/pre-trained models taken from their respective authors):

• OpenCV stereo block matching and Semi-global block matching baselines, with all their parameters

• CREStereo: "Practical Stereo Matching via Cascaded Recurrent Network with Adaptive Correlation" (CVPR 2022)

• RAFT-Stereo: "Multilevel Recurrent Field Transforms for Stereo Matching" (3DV 2021)

• Hitnet: "Hierarchical Iterative Tile Refinement Network for Real-time Stereo Matching" (CVPR 2021)

• STereo TRansformers: "Revisiting Stereo Depth Estimation From a Sequence-to-Sequence Perspective with Transformers" (ICCV 2021)

• Chang et al. RealtimeStereo: "Attention-Aware Feature Aggregation for Real-time Stereo Matching on Edge Devices" (ACCV 2020)

• DistDepth: "Toward Practical Monocular Indoor Depth Estimation" (CVPR 2022). This one is actually a monocular method, only using the left image.

• Depth Anything V3: metric monocular depth estimation. This uses the DA3METRIC-LARGE ONNX export, only using the left image.

• DUSt3R: "Geometric 3D Vision Made Easy" (CVPR 2024). Dense Unconstrained Stereo 3D Reconstruction using a ViT-Large encoder/cross-attention decoder pair. Weights are ~2.3 GB and downloaded on first use. Non-commercial only (CC BY-NC-SA 4.0).

See below for more details / credits to get each of these working, and check this blog post for more results, including performance numbers.

https://user-images.githubusercontent.com/541507/169557430-48e62510-60c2-4a2b-8747-f9606e405f74.mp4

Getting started

Installation

python3 -m pip install stereodemo

For local development, install the locked environment with uv:

uv sync

Then run commands through uv:

uv run stereodemo datasets
uv run python tests/test_methods.py

Running it

With an OAK-D camera

To capture data directly from an OAK-D camera, use:

stereodemo --oak

Then click on Next Image to capture a new one.

With image files

If you installed stereodemo from pip, then just launch stereodemo and it will show some embedded sample images captured with an OAK-D camera.

A tiny subset of some popular datasets is also included in this repository. Just provide a folder to stereodemo and it'll look for left/right pairs (either im0/im1 or left/right in the names):

# To evaluate on the oak-d images
stereodemo datasets/oak-d 

# To cycle through all images
stereodemo datasets

Then click on Next Image to cycle through the images.

Sample images included in this repository:

• drivingstereo: outdoor driving.
• middlebury_2014: high-res objects.
• eth3d: outdoor and indoor scenes.
• sceneflow: synthetic rendering of objects.
• oak-d: indoor images I captured with my OAK-D lite camera.
• kitti2015: outdoor driving (only one image).

Dependencies

pip will install the dependencies automatically. Here is the list:

• Open3D. For the point cloud visualization and the GUI.
• OpenCV. For image loading and the traditional block matching baselines.
• onnxruntime. To run pretrained models in the ONNX format.
• pytorch. To run pretrained models exported as torch script.
• depthai. Optional, to grab images from a Luxonis OAK camera.

DUSt3R is supported as an experimental method through a minimal local PyTorch inference port, so it does not require installing the official DUSt3R package. Its checkpoints are large, and the official code and models are licensed for non-commercial use only.

Credits for each method

I did not implement any of these myself, but just collected pre-trained models or converted them to torch script / ONNX.

• CREStereo

  • Official implementation and pre-trained models: https://github.com/megvii-research/CREStereo
  • Model Zoo for the ONNX models: https://github.com/PINTO0309/PINTO_model_zoo/tree/main/284_CREStereo
  • Port to ONNX + sample loading code: https://github.com/ibaiGorordo/ONNX-CREStereo-Depth-Estimation

• RAFT-Stereo

  • Official implementation and pre-trained models: https://github.com/princeton-vl/RAFT-Stereo
  • I exported the pytorch implementation to torch script via tracing, with minor modifications of the source code.
  • Their fastest implementation was not imported.

• Hitnet

  • Official implementation and pre-trained models: https://github.com/google-research/google-research/tree/master/hitnet
  • Model Zoo for the ONNX models: https://github.com/PINTO0309/PINTO_model_zoo/tree/main/142_HITNET
  • Port to ONNX + sample loading code: https://github.com/ibaiGorordo/ONNX-HITNET-Stereo-Depth-estimation

• Stereo Transformers

  • Official implementation and pre-trained models: https://github.com/mli0603/stereo-transformer
  • Made some small changes to allow torch script export via tracing.
  • The exported model currently fails with GPU inference, so only CPU inference is enabled.

• Chang et al. RealtimeStereo

  • Official implementation and pre-trained models: https://github.com/JiaRenChang/RealtimeStereo
  • I exported the pytorch implementation to torch script via tracing with some minor changes to the code https://github.com/JiaRenChang/RealtimeStereo/pull/15 . See chang_realtimestereo_to_torchscript_onnx.py.

• DistDepth

  • Official implementation and pre-trained models https://github.com/facebookresearch/DistDepth
  • I exported the pytorch implementaton to torch script via tracing, see the changes.

• DUSt3R

  • Official implementation and pre-trained models: https://github.com/naver/dust3r
  • Minimal inference code adapted from: https://github.com/ibaiGorordo/dust3r-pytorch-inference-minimal
  • DUSt3R predicts 3D point maps rather than stereo disparity. This adapter estimates DUSt3R's implicit focal length from the left point map and the predicted baseline from the right point map (assuming a rectified pair), then uses f_dust3r * b_dust3r / Z_dust3r directly as the pixel disparity. No metric-scale recovery via the user's calibration is needed for the disparity output.
  • The official DUSt3R code and checkpoints are licensed under CC BY-NC-SA 4.0.

• Depth Anything V3

  • Official project: https://github.com/DepthAnything/Depth-Anything-V3
  • ONNX model export used by stereodemo: https://huggingface.co/TillBeemelmanns/Depth-Anything-V3-ONNX
  • Preprocessing and metric-depth postprocessing adapted from https://github.com/ika-rwth-aachen/ros2-depth-anything-v3-trt
  • The adapter follows that postprocessing and scales raw depth from the model's 300 px reference focal length to the input calibration focal length.
  • This is a monocular method. It predicts metric depth from the left image, then stereodemo converts that depth to disparity using the stereo calibration so it can reuse the point-cloud visualization pipeline.
  • The model's sky output is used conservatively: when the sky mask covers most of the image, stereodemo keeps the raw depth instead of filling sky pixels, because the sky head can otherwise flatten outdoor driving scenes.

License

The code of stereodemo is MIT licensed, but the pre-trained models are subject to the license of their respective implementation.

The sample images have the license of their respective source, except for datasets/oak-d which is licenced under Creative Commons Attribution 4.0 International License.