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orientation estimation

Orientation estimation is the computational process of determining the rotational alignment, angular direction, or heading of an entity relative to a specified reference frame or coordinate system. Within computer vision, robotics, and image processing, it involves calculating rotational parameters, such as Euler angles, rotation matrices, or directional vectors, for objects, sensors, local feature patches, or structural patterns from sensor data like digital images and point clouds. This estimation is critical for understanding spatial relationships, enabling accurate three-dimensional object detection, camera pose tracking, invariant feature matching, and the analysis of directional textures in automated systems.

4 items

SliceMatch: Geometry-Guided Aggregation for Cross-View Pose Estimation

SliceMatch: Geometry-Guided Aggregation for Cross-View Pose Estimation

Ted de Vries Lentsch, Zimin Xia, Holger Caesar, Julian F. P. Kooij

OrganizationsDelft University of Technology

Why you should read this

Proposes a geometry-guided cross-view camera pose estimation method that splits the field of view into directional slices to aggregate aerial features via precomputed masks, cutting median localization error on the VIGOR benchmark by up to 50% while running at 150 frames per second.

This work addresses cross-view camera pose estimation, i.e., determining the 3-Degrees-of-Freedom camera pose of a given ground-level image w.r.t. an aerial image of the local area. We propose SliceMatch, which consists of ground and aerial feature extractors, feature aggregators, and a pose predictor. The feature extractors extract dense features from the ground and aerial images. Given a set of candidate camera poses, the feature aggregators construct a single ground descriptor and a set of pose-dependent aerial descriptors. Notably, our novel aerial feature aggregator has a cross-view attention module for ground-view guided aerial feature selection and utilizes the geometric projection of the ground camera’s viewing frustum on the aerial image to pool features. The efficient construction of aerial descriptors is achieved using precomputed masks. SliceMatch is trained using contrastive learning and pose estimation is formulated as a similarity comparison between the ground descriptor and the aerial descriptors. Compared to the state-of-the-art, SliceMatch achieves a 19% lower median localization error on the VIGOR benchmark using the same VGG16 backbone at 150 frames per second, and a 50% lower error when using a ResNet50 backbone.

Added

2026-09-26

Fingerprint Image Enhancement: Algorithm and Performance Evaluation

Fingerprint Image Enhancement: Algorithm and Performance Evaluation

Lin Hong, Yifei Wan, Anil K. Jain

OrganizationsMichigan State University

Why you should read this

Presents an adaptive ridge-frequency and orientation enhancement method that measurably improves fingerprint minutiae quality and verification accuracy.

A critical step in automatic fingerprint matching is to automatically and reliably extract minutiae from the input fingerprint images. However, the performance of a minutiae extraction algorithm relies heavily on the quality of the input fingerprint images. In order to ensure that the performance of an automatic fingerprint identification/verification system will be robust with respect to the quality of input fingerprint images, it is essential to incorporate a fingerprint enhancement algorithm in the minutiae extraction module. We present a fast fingerprint enhancement algorithm, which can adaptively improve the clarity of ridge and valley structures of input fingerprint images based on the estimated local ridge orientation and frequency. We have evaluated the performance of the image enhancement algorithm using the goodness index of the extracted minutiae and the accuracy of an online fingerprint verification system. Experimental results show that incorporating the enhancement algorithm improves both the goodness index and the verification accuracy.

Added

2026-09-14