212 citations · 312 across the 15 of their papers we have counts for
16 papers
Explicit Over Implicit: Enhancing CNNs Via Complex Structure Tensor Representations for Periocular Recognition
Kevin Hernandez-Diaz, Josef Bigun, Fernando Alonso-Fernandez
Our study provides evidence that CNNs struggle to extract orientation features effectively. We show that using the Complex Structure Tensor, which contains compact orientation feat…
Leveraging Large-Scale Face Datasets for Deep Periocular Recognition via Ocular Cropping
Fernando Alonso-Fernandez, Kevin Hernandez-Diaz, Jose Maria Buades Rubio +1
We focus on ocular biometrics, specifically the periocular region (the area around the eye), which offers high discrimination and minimal acquisition constraints. We evaluate three…
Note on the Construction of Structure Tensor
Josef Bigun, Fernado Alonso-Fernandez
This note presents a theoretical discussion of two structure tensor constructions: one proposed by Bigun and Granlund 1987, and the other by Granlund and Knutsson 1995. At first gl…
Deep Network Pruning: A Comparative Study on CNNs in Face Recognition
Fernando Alonso-Fernandez, Kevin Hernandez-Diaz, Jose Maria Buades Rubio +2
The widespread use of mobile devices for all kinds of transactions makes necessary reliable and real-time identity authentication, leading to the adoption of face recognition (FR)…
Understanding and Improving CNNs with Complex Structure Tensor: A Biometrics Study
Kevin Hernandez-Diaz, Josef Bigun, Fernando Alonso-Fernandez
Our study provides evidence that CNNs struggle to effectively extract orientation features. We show that the use of Complex Structure Tensor, which contains compact orientation fea…
Keypoint Description by Symmetry Assessment -- Applications in Biometrics
Anna Mikaelyan, Fernando Alonso-Fernandez, Josef Bigun
We present a model-based feature extractor to describe neighborhoods around keypoints by finite expansion, estimating the spatially varying orientation by harmonic functions. The i…
SqueezerFaceNet: Reducing a Small Face Recognition CNN Even More Via Filter Pruning
Fernando Alonso-Fernandez, Kevin Hernandez-Diaz, Jose Maria Buades Rubio +1
The widespread use of mobile devices for various digital services has created a need for reliable and real-time person authentication. In this context, facial recognition technolog…
Combining multiple matchers for fingerprint verification: A case study in biosecure network of excellence
Fernando Alonso-Fernandez, Julian Fierrez-Aguilar, Hartwig Fronthaler +4
We report on experiments for the fingerprint modality conducted during the First BioSecure Residential Workshop. Two reference systems for fingerprint verification have been tested…
A Comparative Study of Fingerprint Image-Quality Estimation Methods
Fernando Alonso-Fernandez, Julian Fierrez, Javier Ortega-Garcia +4
One of the open issues in fingerprint verification is the lack of robustness against image-quality degradation. Poor-quality images result in spurious and missing features, thus de…
On the Effect of Selfie Beautification Filters on Face Detection and Recognition
Pontus Hedman, Vasilios Skepetzis, Kevin Hernandez-Diaz +2
Beautification and augmented reality filters are very popular in applications that use selfie images captured with smartphones or personal devices. However, they can distort or mod…
Cross-Spectral Periocular Recognition with Conditional Adversarial Networks
Kevin Hernandez-Diaz, Fernando Alonso-Fernandez, Josef Bigun
This work addresses the challenge of comparing periocular images captured in different spectra, which is known to produce significant drops in performance in comparison to operatin…
SqueezeFacePoseNet: Lightweight Face Verification Across Different Poses for Mobile Platforms
Fernando Alonso-Fernandez, Javier Barrachina, Kevin Hernandez-Diaz +1
Virtual applications through mobile platforms are one of the most critical and ever-growing fields in AI, where ubiquitous and real-time person authentication has become critical a…
Spectrum Translation for Cross-Spectral Ocular Matching
Kevin Hernandez Diaz, Fernando Alonso-Fernandez, Josef Bigun
Cross-spectral verification remains a big issue in biometrics, especially for the ocular area due to differences in the reflected features in the images depending on the region and…
Improving Automated Latent Fingerprint Identification using Extended Minutia Types
Ram P. Krish, Julian Fierrez, Daniel Ramos +2
Latent fingerprints are usually processed with Automated Fingerprint Identification Systems (AFIS) by law enforcement agencies to narrow down possible suspects from a criminal data…
Expression Recognition Using the Periocular Region: A Feasibility Study
Fernando Alonso-Fernandez, Josef Bigun, Cristofer Englund
This paper investigates the feasibility of using the periocular region for expression recognition. Most works have tried to solve this by analyzing the whole face. Periocular is th…
A Survey on Periocular Biometrics Research
Fernando Alonso-Fernandez, Josef Bigun
Periocular refers to the facial region in the vicinity of the eye, including eyelids, lashes and eyebrows. While face and irises have been extensively studied, the periocular regio…