4 research outputs found
LFM-3D: Learnable Feature Matching Across Wide Baselines Using 3D Signals
Finding localized correspondences across different images of the same object
is crucial to understand its geometry. In recent years, this problem has seen
remarkable progress with the advent of deep learning-based local image features
and learnable matchers. Still, learnable matchers often underperform when there
exists only small regions of co-visibility between image pairs (i.e. wide
camera baselines). To address this problem, we leverage recent progress in
coarse single-view geometry estimation methods. We propose LFM-3D, a Learnable
Feature Matching framework that uses models based on graph neural networks and
enhances their capabilities by integrating noisy, estimated 3D signals to boost
correspondence estimation. When integrating 3D signals into the matcher model,
we show that a suitable positional encoding is critical to effectively make use
of the low-dimensional 3D information. We experiment with two different 3D
signals - normalized object coordinates and monocular depth estimates - and
evaluate our method on large-scale (synthetic and real) datasets containing
object-centric image pairs across wide baselines. We observe strong feature
matching improvements compared to 2D-only methods, with up to +6% total recall
and +28% precision at fixed recall. Additionally, we demonstrate that the
resulting improved correspondences lead to much higher relative posing accuracy
for in-the-wild image pairs - up to 8.6% compared to the 2D-only approach
NAVI: Category-Agnostic Image Collections with High-Quality 3D Shape and Pose Annotations
Recent advances in neural reconstruction enable high-quality 3D object
reconstruction from casually captured image collections. Current techniques
mostly analyze their progress on relatively simple image collections where
Structure-from-Motion (SfM) techniques can provide ground-truth (GT) camera
poses. We note that SfM techniques tend to fail on in-the-wild image
collections such as image search results with varying backgrounds and
illuminations. To enable systematic research progress on 3D reconstruction from
casual image captures, we propose NAVI: a new dataset of category-agnostic
image collections of objects with high-quality 3D scans along with per-image
2D-3D alignments providing near-perfect GT camera parameters. These 2D-3D
alignments allow us to extract accurate derivative annotations such as dense
pixel correspondences, depth and segmentation maps. We demonstrate the use of
NAVI image collections on different problem settings and show that NAVI enables
more thorough evaluations that were not possible with existing datasets. We
believe NAVI is beneficial for systematic research progress on 3D
reconstruction and correspondence estimation. Project page:
https://navidataset.github.ioComment: NeurIPS 2023 camera ready. Project page:
https://navidataset.github.i
Global Features are All You Need for Image Retrieval and Reranking
Utilizing a two-stage paradigm comprising of coarse image retrieval and
precise reranking, a well-established image retrieval system is formed. It has
been widely accepted for long time that local feature is imperative to the
subsequent stage - reranking, but this requires sizeable storage and computing
capacities. We, for the first time, propose an image retrieval paradigm
leveraging global feature only to enable accurate and lightweight image
retrieval for both coarse retrieval and reranking, thus the name - SuperGlobal.
It consists of several plug-in modules that can be easily integrated into an
already trained model, for both coarse retrieval and reranking stage. This
series of approaches is inspired by the investigation into Generalized Mean
(GeM) Pooling. Possessing these tools, we strive to defy the notion that local
feature is essential for a high-performance image retrieval paradigm. Extensive
experiments demonstrate substantial improvements compared to the state of the
art in standard benchmarks. Notably, on the Revisited Oxford (ROxford)+1M Hard
dataset, our single-stage results improve by 8.2% absolute, while our two-stage
version gain reaches 3.7% with a strong 7568X speedup. Furthermore, when the
full SuperGlobal is compared with the current single-stage state-of-the-art
method, we achieve roughly 17% improvement with a minimal 0.005% time overhead.
Code: https://github.com/ShihaoShao-GH/SuperGlobal.Comment: Accepted to ICCV 202