WACV 2026

Enhanced Back-Projection of Vision Features for 3D Symmetry Detection

Isaac Aguirre Ivan Sipiran

Department of Computer Science, University of Chile

Introduction Image

Abstract

We propose two algorithms for 3D symmetry detection based on enhanced back-projection of vision features extracted from foundation vision models such as DINOv2. Our method enhances back-projection by rendering multiple views of 3D objects, extracting features, and projecting them onto the geometry with two key improvements—Fibonacci view sampling and view rotations—that increase robustness and accuracy. Using these features, we detect symmetry planes and axes through two dedicated algorithms. Experiments on ShapeNet show that our plane detection approach outperforms both traditional geometric and learning-based methods by a wide margin. The method is also efficient, running in seconds on a single 8GB GPU, making it practical for large-scale or real-world applications. Overall, our results demonstrate that enhanced back-projection of vision features offers a simple yet effective framework for solving fundamental 3D geometric problems such as symmetry detection.

Enhanced Back-Projection

Diagram showing the two key enhancements to back-projection: Fibonacci view sampling and view rotations. These improvements increase the robustness and accuracy of the projected features, leading to better symmetry detection results.

Diagram showing the two key enhancements to back-projection: Fibonacci view sampling and view rotations
Diagram illustrating the enhanced back-projection process with Fibonacci view sampling and view rotations.
This produces different feature representations: Raw-Mesh (RM), Point Cloud (PC), Feature-Mesh Sampling (FM), where FM performs the same sampling for geometry and features after RM.
Diagram showing the different feature representations: Raw-Mesh (RM), Point Cloud (PC), Feature-Mesh Sampling (FM)
Diagram illustrating the different feature representations obtained from the enhanced back-projection process.

Planes Algorithm

The plane detection algorithm follows these steps:

  1. Group each point into a trio of similar features
  2. Compute 4 possible candidate planes
  3. Filter planes that pass near the middle of the object, as these represent global symmetries
  4. Check resulting planes using Chamfer distance and output the best computed planes
Planes algorithm diagram
Diagram of the plane detection pipeline.

Axes Algorithm

The axis detection algorithm follows these steps:

  1. Group each point into an L-sized group of similar features
  2. Use RANSAC to produce circles for each group
  3. Cluster resulting circles from all groups and keep the largest cluster
  4. Compute a mean circle and output the axis defined by the mean circle's center and normal vector
Axes algorithm diagram
Diagram of the axis detection pipeline.

Visual Results

Both algorithms use 114 views with DINOv2 small. Planes use FM10K with Fibonacci sampling and 4 rotations. Axes use RM with Fibonacci sampling and 4 rotations.

Plane Detection Results

FM10K (left) and RM (right), where the right image is for visual reference only to show the plane detected using features from the left image. Red outlines indicate detected symmetry planes.

Plane qualitative example 1A Plane qualitative example 1B Plane qualitative example 2A Plane qualitative example 2B Plane qualitative example 3A Plane qualitative example 3B Plane qualitative example 4A Plane qualitative example 4B Plane qualitative example 5A Plane qualitative example 5B Plane qualitative example 6A Plane qualitative example 6B

Axis Detection Results

Qualitative examples using raw mesh representation. Blue outlines indicate detected rotational symmetry axes.

Axis qualitative example 1 Axis qualitative example 2 Axis qualitative example 3 Axis qualitative example 4 Axis qualitative example 5 Axis qualitative example 6

BibTeX

@InProceedings{Aguirre_2026_WACV,
    author    = {Aguirre, Isaac and Sipiran, Ivan},
    title     = {Enhanced Back-Projection of Vision Features for 3D Symmetry Detection},
    booktitle = {Proceedings of the IEEE/CVF Winter Conference on Applications of Computer Vision (WACV)},
    month     = {March},
    year      = {2026},
    pages     = {66-76}
}