EDBT 2026 Demo / reviewers in the wild / expert
Peter Peer
dblp:04/6943
· DBLP profile ↗
51ranked-venue papers
3as first author
34since 2021 · last 2026
0000-0001-9744-4035ORCID · corroborated
Domains — the database's venue-derived domains; a paper can count in several
Artificial intelligence and machine learning · 40 · 2 first-author · 26 since 2021Graphics, computer vision, multimedia, augmented reality and games · 33 · 1 first-author · 24 since 2021Security and privacy · 18 · 15 since 2021Human-computer interaction and ubiquitous computing · 15 · 12 since 2021Applied, interdisciplinary, general and emerging computing · 2 · 2 since 2021
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2026 | FunFace: Feature Utility and Norm Estimation for Face RecognitionabstractFace Recognition (FR) is used in a variety of application domains, from entertainment and; to security and surveillance. Such applications rely on the FR model to be robust and perform well in a variety of settings. To achieve this, state-of-the-art FR models typically use expressive adaptive margin loss functions, which tie the feature norm to concepts related to sample quality, such as recognizability and perceptual image quality. Recently, through the development of Face Image Quality Assessment (FIQA) techniques, biometric utility has become the preferred measure of face-image quality and has been shown to be a better predictor of the usefulness of samples for face recognition compared to more human-centric aspects, such as resolution, blur, and lighting, tied to general image quality. While image quality expressed through feature norms exhibits a certain level of correlation with biometric utility, it does not fully encapsulate all aspects of utility. To address this point, we propose a new adaptive margin loss, FunFace (Face Recognition Through Utility and Norm Estimation), which incorporates biometric utility, estimated by the Certainty Ratio, into the adaptive margin, taking inspiration from AdaFace. We show that FunFace (when used to train a face recognition model) achieves competitive results to other state-of-the-art FR models on benchmarks containing high-quality samples, while surpassing them on low quality benchmarks. The code is available at https://github.com/LSIbabnikz/FunFace. Ziga Babnik, Fadi Boutros, Naser Damer, Deepak Kumar Jain 0001, Peter Peer, Vitomir Struc |
FG | 5 |
| 2026 | IDSync: Improving diffusion models through identity classificationabstractNasl. z nasl. zaslona. Jernej Sabadin, Darian Tomasevic, Blaz Meden, Peter Peer, Vitomir Struc |
FG | 4 |
| 2026 | FaceMINT: A library for gaining insights into biometric face recognition via mechanistic interpretabilityabstractDeep-learning models, including those used in biometric recognition, have achieved remarkable performance on benchmark datasets as well as real-world recognition tasks. However, a major drawback of these models is their lack of transparency in decision-making. Mechanistic interpretability has emerged as a promising research field intended to help us gain insights into such models, but its application to biometric data remains limited. In this work, we bridge this gap by introducing the FaceMINT library, a publicly available Python library (build on top of Pytorch) that enables biometric researchers to inspect their models through mechanistic interpretability. It provides a plug-and-play solution that allows researchers to seamlessly switch between the analyzed biometric models, evaluate state-of-the-art sparse autoencoders, select from various image parametrizations, and fine-tune hyperparameters. Using a large scale Glint360K dataset, we demonstrate the usability of FaceMINT by applying its functionality to two state-of-the-art (deep-learning) face recognition models: AdaFace, based on Convolutional Neural Networks (CNN), and SwinFace, based on transformers. The proposed library implements various sparse auto-encoders (SAEs), including vanilla SAE, Gated SAE, JumpReLU SAE, and TopK SAE, which have achieved state-of-the-art results in the mechanistic interpretability of large language models. Our study highlights the promise of mechanistic interpretability in the biometric field, providing new avenues for researchers to explore model transparency and refine biometric recognition systems. The library is publicly available at www.gitlab.com/peterrot/facemint . Peter Rot, Robert Jutresa, Peter Peer, Vitomir Struc, Walter J. Scheirer, Klemen Grm |
Image Vis. Comput. | 3 |
| 2025 | SelfMAD: Enhancing Generalization and Robustness in Morphing Attack Detection via Self-Supervised LearningabstractWith the continuous advancement of generative models, face morphing attacks have become a significant challenge for existing face verification systems due to their potential use in identity fraud and other malicious activities. Contemporary Morphing Attack Detection (MAD) approaches frequently rely on supervised, discriminative models trained on examples of bona fide and morphed images. These models typically perform well with morphs generated with techniques seen during training, but often lead to sub-optimal performance when subjected to novel unseen morphing techniques. While unsupervised models have been shown to perform better in terms of generalizability, they typically result in higher error rates, as they struggle to effectively capture features of subtle artifacts. To address these shortcomings, we present SelfMAD, a novel self-supervised approach that simulates general morphing attack artifacts, allowing classifiers to learn generic and robust decision boundaries without overfitting to the specific artifacts induced by particular face morphing methods. Through extensive experiments on widely used datasets, we demonstrate that SelfMAD significantly outperforms current state-of-theart MADs, reducing the detection error by more than $\mathbf{6 4} \%$ in terms of EER when compared to the strongest unsupervised competitor, and by more than $66 \%$, when compared to the best performing discriminative MAD model, tested in crossmorph settings. The source code for SelfMAD is available at https://github.com/LeonTodorov/SelfMAD. Marija Ivanovska, Leon Todorov, Naser Damer, Deepak Kumar Jain 0001, Peter Peer, Vitomir Struc |
FG | 5 |
| 2025 | ID-Booth: Identity-consistent Face Generation with Diffusion ModelsabstractRecent advances in generative modeling have enabled the generation of high-quality synthetic data that is applicable in a variety of domains, including face recognition. Here, state-of-the-art generative models typically rely on conditioning and fine-tuning of powerful pretrained diffusion models to facilitate the synthesis of realistic images of a desired identity. Yet, these models often do not consider the identity of subjects during training, leading to poor consistency between generated and intended identities. In contrast, methods that employ identity-based training objectives tend to overfit on various aspects of the identity, and in turn, lower the diversity of images that can be generated. To address these issues, we present in this paper a novel generative diffusion-based framework, called ID-Booth. ID-Booth consists of a denoising network responsible for data generation, a variational auto-encoder for mapping images to and from a lower-dimensional latent space and a text encoder that allows for prompt-based control over the generation procedure. The framework utilizes a novel triplet identity training objective and enables identity-consistent image generation while retaining the synthesis capabilities of pretrained diffusion models. Experiments with a state-of-the-art latent diffusion model and diverse prompts reveal that our method facilitates better intra-identity consistency and inter-identity separability than competing methods, while achieving higher image diversity. In turn, the produced data allows for effective augmentation of small-scale datasets and training of betterperforming recognition models in a privacy-preserving manner. The source code for the ID-Booth framework is publicly available at https://github.com/dariant/ID-Booth. Darian Tomasevic, Fadi Boutros, Chenhao Lin, Naser Damer, Vitomir Struc, Peter Peer |
FG | 6 |
| 2025 | FROQ1: Observing Face Recognition Models for Efficient Quality AssessmentabstractFace Recognition (FR) plays a crucial role in many critical (high-stakes) applications, where errors in the recognition process can lead to serious consequences. Face Image Quality Assessment (FIQA) techniques enhance FR systems by providing quality estimates of face samples, enabling the systems to discard samples that are unsuitable for reliable recognition or lead to low-confidence recognition decisions. Most state-of-the-art FIQA techniques rely on extensive supervised training to achieve accurate quality estimation. In contrast, unsupervised techniques eliminate the need for additional training but tend to be slower and typically exhibit lower performance. In this paper, we introduce FROQ1(Face Recognition Observer of Quality), a semi-supervised, training-free approach that leverages specific intermediate representations within a given FR model to estimate face-image quality, and combines the efficiency of supervised FIQA models with the training-free approach of unsupervised methods. A simple calibration step based on pseudo-quality labels allows FROQ to uncover specific representations, useful for quality assessment, in any modern FR model. To generate these pseudo-labels, we propose a novel unsupervised FIQA technique based on sample perturbations. Comprehensive experiments with four state-of-the-art FR models and eight benchmark datasets show that FROQ leads to highly competitive results compared to the state-of-the-art, achieving both strong performance and efficient runtime, without requiring explicit training. The code for FROQ is available from: https://github.com/LSIbabnikz/FROQ Ziga Babnik, Deepak Kumar Jain 0001, Peter Peer, Vitomir Struc |
IJCB | 3 |
| 2025 | 2nd Latent in the Wild Fingerprint Recognition CompetitionabstractThis paper presents a summary of the 2nd Latent in the Wild Fingerprint Recognition Competition held at the 2025 International Joint Conference on Biometrics. The competition has two tracks: latent fingerprint 1) recognition, and 2) quality assessment. It attracted a total of 12 participating teams from academia and industry for both tracks, representing 10 countries. In total, 8 valid submissions were evaluated by the organizers. The competition aimed to advance the state-of-the-art in latent fingerprint recognition and quality assessment by providing a challenging dataset of latent fingerprints collected in natural, non-ideal conditions. This paper summarizes the dataset, evaluation protocols, submitted methods, and the competition results. Xinwei Liu 0001, Renfang Wang, Peiyuan Zhang, Tim Oblak, Lara Anzur, Peter Peer, Evaldas Borcovas, Arturas Nakvosas, Ignas Mataitis, Valdemaras Pasvenskas, Andrius Stankevicius, Marko Lange, David Stumpf, Sven Utcke, Patryk Szwargulski, Fantin Girard, Zacharie Legault, Ekansh Thakur, Jaishana Bindhu Priya, Pavan Kumar C, Ramachandra Raghavendra, Kiran B. Raja |
IJCB | 7 |
| 2025 | Second Competition on Presentation Attack Detection on ID CardabstractThis work summarises and reports the results of the second Presentation Attack Detection competition on ID cards. This new version includes new elements compared to the previous one. (1) An automatic evaluation platform was enabled for automatic benchmarking; (2) Two tracks were proposed in order to evaluate algorithms and datasets respectively; and (3) A new ID card dataset was shared with Track 1 teams to serve as the baseline dataset for the training and optimisation. The Hochschule Darmstadt, Fraunhofer-IGD, and Facephi company jointly organised this challenge. 20 teams were registered, and 74 submitted models were evaluated. For Track 1, the "Dragons" team reached first place with an Average Ranking and Equal Error rate (EER) of (AVRank) of 40.48% and 11.44% EER, respectively. For the more challenging approach in Track 2, the "Incode" team reached the best results with an AVRank of 14.76% and 6.36% EER, improving on the results of the first edition of 74.30% and 21.87% EER, respectively. These results suggest that PAD on ID cards is improving, but it is still a challenging problem related to the number of images, especially of bona fide images. Juan E. Tapia, Mario Nieto-Hidalgo, Juan M. Espín, Alvaro S. Rocamora, Javier Barrachina, Naser Damer, Christoph Busch 0001, Marija Ivanovska, Leon Todorov, Renat Khizbullin, Lazar Lazarevich, Aleksei Grishin, Daniel Schulz, Amir Mohammadi, Ketan Kotwal, Sébastien Marcel, Raghavendra Mudgalgundurao, Kiran B. Raja, Patrick Schuch Shell, Sushrut Patwardhan, Ramachandra Raghavendra, Pedro Couto Pereira, João Ribeiro Pinto, Mariana Xavier, Andres Valenzuela, Rodrigo Lara, Borut Batagelj, Marko Peterlin, Peter Peer, Ajnas Muhammed, Diogo Nunes, Nuno Gonçalves 0001 |
IJCB | 30 |
| 2025 | Privacy-enhancing Sclera Segmentation Benchmarking Competition: SSBC 2025abstractThis paper presents a summary of the 2025 Sclera Segmentation Benchmarking Competition (SSBC), which focused on the development of privacy-preserving sclera-segmentation models trained using synthetically generated ocular images. The goal of the competition was to evaluate how well models trained on synthetic data perform in comparison to those trained on real-world datasets. The competition featured two tracks: (i) one relying solely on synthetic data for model development, and (ii) one combining/mixing synthetic with (a limited amount of) real-world data. A total of nine research groups submitted diverse segmentation models, employing a variety of architectural designs, including transformer-based solutions, lightweight models, and segmentation networks guided by generative frameworks. Experiments were conducted across three evaluation datasets containing both synthetic and real-world images, collected under diverse conditions. Results show that models trained entirely on synthetic data can achieve competitive performance, particularly when dedicated training strategies are employed, as evidenced by the top performing models that achieved F1scores of over 0.8 in the synthetic data track. Moreover, performance gains in the mixed track were often driven more by methodological choices rather than by the inclusion of real data, highlighting the promise of synthetic data for privacy-aware biometric development. The code and data for the competition is available at: https://github.com/dariant/SSBC_2025. Matej Vitek, Darian Tomasevic, Abhijit Das 0001, Sabari Nathan, Gökhan Özbulak, G. A. T. Özbulak, Jean-Paul Calbimonte, André Anjos, Hariohm Hemant Bhatt, Dhruv Dhirendra Premani, Jay Chaudhari, Caiyong Wang, Iyyakutti Iyappan Ganapathi, Syed Sadaf Ali, Divya Velayudan, Maregu Assefa, Naoufel Werghi, Zachary A. Daniels, Leeon John, Ritesh Vyas, Jalil Nourmohammadi Khiarak, Taher Akbari Saeed, Mahsa Nasehi, Ali Kianfar, Mobina Pashazadeh Panahi, Geetanjali Sharma, Pushp Raj Panth, Ramachandra Raghavendra, Aditya Nigam, Umapada Pal 0001, Peter Peer, Vitomir Struc |
IJCB | 34 |
| 2025 | Evading Deepfake Detectors via Adversarially Degrading and Restoring Forged ImagesabstractDeepfake detection can prevent the misuse of deep generative techniques but is known to be vulnerable to adversarial attacks. However, most existing attacks introduce noticeable noise, resulting in an unsatisfactory trade-off between attack effectiveness and imperceptibility. In this paper, we propose a new generative attack based on adversarially Degrading and Restoring (DR) fake images, eliminating the use of noisy perturbations. Specifically, degradation works by removing high-frequency deepfake artifacts with the guidance of adversarial loss from the detector, and the subsequent restoration aims to maintain the image quality by restoring high-frequency details of natural images. Our analysis confirms that combining degradation and restoration effectively aligns the distribution of adversarial (fake) images and real images in both frequency and pixel domains. Our experimental results across eight popular detectors and three popular deep-fake datasets prove the effectiveness of our method compared with several state-of-the-art methods. Our code is available at https://github.com/fanoflck/DR_attack. Zhengli Shi, Chenhao Lin, Zhengyu Zhao 0001, Peter Peer, Chao Shen 0001 |
ICME | 4 |
| 2024 | DiCTI: Diffusion-based Clothing Designer via Text-guided InputabstractRecent developments in deep generative models have opened up a wide range of opportunities for image synthesis, leading to significant changes in various creative fields, including the fashion industry. While numerous methods have been proposed to benefit buyers, particularly in virtual try-on applications, there has been relatively less focus on facilitating fast prototyping for designers and customers seeking to order new designs. To address this gap, we introduce DiCTI (Diffusion-based Clothing Designer via Text-guided Input), a straightforward yet highly effective approach that allows designers to quickly visualize fashion-related ideas using text inputs only. Given an image of a person and a description of the desired garments as input, DiCTI automatically generates multiple high-resolution, photorealistic images that capture the expressed semantics. By leveraging a powerful diffusion-based inpainting model conditioned on text inputs, DiCTI is able to synthesize convincing, high-quality images with varied clothing designs that viably follow the provided text descriptions, while being able to process very diverse and challenging inputs, captured in completely unconstrained settings. We evaluate DiCTI in comprehensive experiments on two different datasets (VITON-HD and Fashionpedia) and in comparison to the state-of-the-art (SoTa). The results of our experiments show that DiCTI convincingly outperforms the SoTA competitor in generating higher quality images with more elaborate garments and superior text prompt adherence, both according to standard quantitative evaluation measures and human ratings, generated as part of a user study. The source code of DiCTI will be made publicly available. Ajda Lampe, Julija Stopar, Deepak Kumar Jain 0001, Shinichiro Omachi, Peter Peer, Vitomir Struc |
FG | 5 |
| 2024 | ASPECD: Adaptable Soft-Biometric Privacy-Enhancement Using Centroid Decoding for Face VerificationabstractState-of-the-art face recognition models commonly extract information-rich biometric templates from the input images that are then used for comparison purposes and identity inference. While these templates encode identity information in a highly discriminative manner, they typically also capture other potentially sensitive facial attributes, such as age, gender or ethnicity. To address this issue, Soft-Biometric Privacy-Enhancing Techniques (SB-PETs) were proposed in the literature that aim to suppress such attribute information, and, in turn, alleviate the privacy risks associated with the extracted biometric templates. While various SB-PETs were presented so far, existing approaches do not provide dedicated mechanisms to determine which soft-biometrics to exclude and which to retain. In this paper, we address this gap and introduce ASPECD, a modular framework designed to selectively suppress binary and categorical soft-biometrics based on users' privacy preferences. ASPECD consists of multiple sequentially connected components, each dedicated for privacy-enhancement of an individual soft-biometric attribute. The proposed framework suppresses attribute information using a Moment-based Disentanglement process coupled with a centroid decoding procedure, ensuring that the privacy-enhanced templates are directly comparable to the templates in the original embedding space, regardless of the soft-biometric modality being suppressed. To validate the performance of ASPECD, we conduct experiments on a large-scale face dataset and with five state-of-the-art face recognition models, demonstrating the effectiveness of the proposed approach in suppressing single and multiple soft-biometric attributes. Our approach achieves a competitive privacy-utility trade-off compared to the state-of-the-art methods in scenarios that involve enhancing privacy w.r.t. gender and ethnicity attributes. The model will be made publicly available. Peter Rot, Philipp Terhörst, Peter Peer, Vitomir Struc |
FG | 3 |
| 2024 | Enhancing Gender Privacy with Photo-Realistic Fusion of Disentangled Spatial SegmentsabstractSoft-biometric privacy enhancing techniques (SB-PETs) transform facial images to preserve identity while preventing the automatic extraction of soft-biometrics by confusing machines through noise injections or attribute obfuscation. However, existing SB-PETs often sacrifice image quality for privacy enhancement, limiting practical usage, especially in applications that allow for human inspection. To address these issues, we introduce a novel SB-PET that (i) generates photo-realistic images with obscured gender information, which makes attribute extraction challenging for machine-learning models, but also human observers, and (ii) preserves identity to a significant extent. The proposed approach, abbreviated PriDSS, operates in the latent space of the StyleGANv2 model and aims to (i) preserve the appearance of facial parts from the input image carrying identity information, and (ii) incorporate global context from images of the opposite gender, thus, obscuring the original gender information. PriDSS shows promising results when compared to state-of-the-art techniques from the literature, and leads to competitive gender-privacy and face-verification performance, while ensuring superior photo-realism. Peter Rot, Janez Krizaj, Peter Peer, Vitomir Struc |
ICASSP | 3 |
| 2024 | Latent in the Wild Fingerprint Recognition CompetitionabstractThis paper presents a summary of the Latent in the Wild Fingerprint Recognition Competition held at the 2024 International Joint Conference on Biometrics (IJCB 2024). The competition attracted a total of 6 participating teams from academia and industry, representing 6 countries. In total, 3 valid submissions were evaluated by the organizers. The competition aimed to advance the state-of-the-art in latent fingerprint recognition by providing a challenging dataset of latent fingerprints collected in natural, non-ideal conditions. This paper summarizes the dataset, evaluation criteria, participant methods, and the competition results. Xinwei Liu 0001, Renfang Wang, Tim Oblak, Lara Anzur, Peter Peer, Evaldas Borcovas, Kiran B. Raja |
IJCB | 5 |
| 2024 | Simplification of Image Segmentation and Object Detection Teaching Materials
Ziga Emersic, Gregor Hrastnik, Natasa Meh Peer, Vasja Lev Kirn, Aljaz Justin, Jovana Videnovic, Luka Markicevic, Peter Peer |
IDEAL (2) | 8 |
| 2024 | Educational Computer Vision Materials for Classification and Tracking of Objects
Ziga Emersic, Gregor Hrastnik, Natasa Meh Peer, Vasja Lev Kirn, Aljaz Justin, Jovana Videnovic, Luka Markicevic, Peter Peer |
IDEAL (2) | 8 |
| 2024 | Generating bimodal privacy-preserving data for face recognitionabstractThe performance of state-of-the-art face recognition systems depends crucially on the availability of large-scale training datasets. However, increasing privacy concerns nowadays accompany the collection and distribution of biometric data, which has already resulted in the retraction of valuable face recognition datasets. The use of synthetic data represents a potential solution, however, the generation of privacy-preserving facial images useful for training recognition models is still an open problem. Generative methods also remain bound to the visible spectrum, despite the benefits that multispectral data can provide. To address these issues, we present a novel identity-conditioned generative framework capable of producing large-scale recognition datasets of visible and near-infrared privacy-preserving face images. The framework relies on a novel identity-conditioned dual-branch style-based generative adversarial network to enable the synthesis of aligned high-quality samples of identities determined by features of a pretrained recognition model. In addition, the framework incorporates a novel filter to prevent samples of privacy-breaching identities from reaching the generated datasets and improve both identity separability and intra-identity diversity. Extensive experiments on six publicly available datasets reveal that our framework achieves competitive synthesis capabilities while preserving the privacy of real-world subjects. The synthesized datasets also facilitate training more powerful recognition models than datasets generated by competing methods or even small-scale real-world datasets. Employing both visible and near-infrared data for training also results in higher recognition accuracy on real-world visible spectrum benchmarks. Therefore, training with multispectral data could potentially improve existing recognition systems that utilize only the visible spectrum, without the need for additional sensors. Darian Tomasevic, Fadi Boutros, Naser Damer, Peter Peer, Vitomir Struc |
Eng. Appl. Artif. Intell. | 4 |
| 2024 | PrivacyProber: Assessment and Detection of Soft-Biometric Privacy-Enhancing TechniquesabstractSoft–biometric privacy–enhancing techniques represent machine learning methods that aim to: (i) mitigate privacy concerns associated with face recognition technology by suppressing selected soft–biometric attributes in facial images (e.g., gender, age, ethnicity) and (ii) make unsolicited extraction of sensitive personal information infeasible. Because such techniques are increasingly used in real–world applications, it is imperative to understand to what extent the privacy enhancement can be inverted and how much attribute information can be recovered from privacy–enhanced images. While these aspects are critical, they have not been investigated in the literature so far. In this paper, we, therefore,study the robustnessof several state–of–the–art soft–biometric privacy–enhancing techniques to attribute recovery attempts. We propose PrivacyProber, a high–level framework for restoring soft–biometric information from privacy–enhanced facial images, and apply it for attribute recovery in comprehensive experiments on three public face datasets, i.e., LFW, MUCT and Adience. Our experiments show that the proposed framework is able to restore a considerable amount of suppressed information, regardless of the privacy–enhancing technique used (e.g., adversarial perturbations, conditional synthesis, etc.), but also that there are significant differences between the considered privacy models. These results point to the need for novel mechanisms that can improve the robustness of existing privacy–enhancing techniques and secure them against potential adversaries trying to restore suppressed information. Additionally, we demonstrate that PrivacyProber can also be used to detect privacy–enhancement in facial images (under black–box assumptions) with high accuracy. Specifically, we show that a detection procedure can be developed around the proposed framework that islearning freeand, therefore, generalizes well across different data characteristics and privacy–enhancing techniques. Peter Rot, Klemen Grm, Peter Peer, Vitomir Struc |
IEEE Trans. Dependable Secur. Comput. | 3 |
| 2023 | GlassesGAN: Eyewear Personalization Using Synthetic Appearance Discovery and Targeted Subspace ModelingabstractWe present GlassesGAN, a novel image editing frame-work for custom design of glasses, that sets a new standard in terms of output-image quality, edit realism, and continuous multi-style edit capability. To facilitate the editing process with GlassesGAN, we propose a Targeted Subspace Modelling (TSM) procedure that, based on a novel mechanism for (synthetic) appearance discovery in the latent space of a pre-trained GAN generator, constructs an eyeglasses-specific (latent) subspace that the editing framework can utilize. Additionally, we also introduce an appearance-constrained subspace initialization (SI) technique that centers the latent representation of the given input image in the well-defined part of the constructed sub-space to improve the reliability of the learned edits. We test GlassesGAN on two (diverse) high-resolution datasets (CelebA-HQ and SiblingsDB-HQf) and compare it to three state-of-the-art baselines, i.e., InterfaceGAN, GANSpace, and MaskGAN. The reported results show that GlassesGAN convincingly outperforms all competing techniques, while offering functionality (e.g., fine-grained multi-style editing) not available with any of the competitors. The source code for GlassesGAN is made publicly available. Richard Plesh, Peter Peer, Vitomir Struc |
CVPR | 2 |
| 2023 | DifFIQA: Face Image Quality Assessment Using Denoising Diffusion Probabilistic ModelsabstractModern face recognition (FR) models excel in constrained scenarios, but often suffer from decreased performance when deployed in unconstrained (real-world) environments due to uncertainties surrounding the quality of the captured facial data. Face image quality assessment (FIQA) techniques aim to mitigate these performance degradations by providing FR models with sample-quality predictions that can be used to reject low-quality samples and reduce false match errors. However, despite steady improvements, ensuring reliable quality estimates across facial images with diverse characteristics remains challenging. In this paper, we present a powerful new FIQA approach, named DifFIQA, which relies on denoising diffusion probabilistic models (DDPM) and ensures highly competitive results. The main idea behind the approach is to utilize the forward and backward processes of DDPMs to perturb facial images and quantify the impact of these perturbations on the corresponding image embeddings for quality prediction. Because the diffusion-based perturbations are computationally expensive, we also distill the knowledge encoded in DifFIQA into a regression-based quality predictor, called DifFIQA(R), that balances performance and execution time. We evaluate both models in comprehensive experiments on 7 diverse datasets, with 4 target FR models and against 10 state-of-the-art FIQA techniques with highly encouraging results. The source code is available from: https://github.com/LSIbabnikz/DifFIQA. Ziga Babnik, Peter Peer, Vitomir Struc |
IJCB | 2 |
| 2023 | Sclera Segmentation and Joint Recognition Benchmarking Competition: SSRBC 2023abstractThis paper presents the summary of the Sclera Segmentation and Joint Recognition Benchmarking Competition (SSRBC 2023) held in conjunction with IEEE International Joint Conference on Biometrics (IJCB 2023). Different from the previous editions of the competition, SSRBC 2023 not only explored the performance of the latest and most advanced sclera segmentation models, but also studied the impact of segmentation quality on recognition performance. Five groups took part in SSRBC 2023 and submitted a total of six segmentation models and one recognition technique for scoring. The submitted solutions included a wide variety of conceptually diverse deep-learning models and were rigorously tested on three publicly available datasets, i.e., MASD, SBVPI and MOBIUS. Most of the segmentation models achieved encouraging segmentation and recognition performance. Most importantly, we observed that better segmentation results always translate into better verification performance. Abhijit Das 0001, Saurabh Atreya, Aritra Mukherjee, Matej Vitek, Caiyong Wang, Guangzhe Zhao, Fadi Boutros, Patrick Siebke, Jan Niklas Kolf, Naser Damer, Sun Ye, Lu Hexin, Fan Aobo, You Sheng, Sabari Nathan, R. Suganya 0001, Rampriya Rajendran Shanthi, Geetanjali Sharma, P. Priyanka, Aditya Nigam, Peter Peer, Umapada Pal 0001, Vitomir Struc |
IJCB | 22 |
| 2023 | The Unconstrained Ear Recognition Challenge 2023: Maximizing Performance and Minimizing BiasabstractThe paper provides a summary of the 2023 Unconstrained Ear Recognition Challenge (UERC), a benchmarking effort focused on ear recognition from images acquired in uncontrolled environments. The objective of the challenge was to evaluate the effectiveness of current ear recognition techniques on a challenging ear dataset while analyzing the techniques from two distinct aspects, i.e., verification performance and bias with respect to specific demographic factors, i.e., gender and ethnicity. Seven research groups participated in the challenge and submitted a seven distinct recognition approaches that ranged from descriptor-based methods and deep-learning models to ensemble techniques that relied on multiple data representations to maximize performance and minimize bias. A comprehensive investigation into the performance of the submitted models is presented, as well as an in-depth analysis of bias and associated performance differentials due to differences in gender and ethnicity. The results of the challenge suggest that a wide variety of models (e.g., transformers, convolutional neural networks, ensemble models) is capable of achieving competitive recognition results, but also that all of the models still exhibit considerable performance differentials with respect to both gender and ethnicity. To promote further development of unbiased and effective ear recognition models, the starter kit of UERC 2023 together with the baseline model, and training and test data is made available from: http://ears.fri.uni-lj.si/ Ziga Emersic, Tetsushi Ohki, Muku Akasaka, Takahiko Arakawa, Soshi Maeda, Masora Okano, Yuya Sato, Anjith George, Sébastien Marcel, Iyyakutti Iyappan Ganapathi, Syed Sadaf Ali, Sajid Javed, Naoufel Werghi, S. G. Isik, Erdi Saritas, Hazim Kemal Ekenel, V. Hudovernik, Jan Niklas Kolf, Fadi Boutros, Naser Damer, G. Sharma, Aman Kamboj, Aditya Nigam, Deepak Kumar Jain 0001, G. Cámara-Chávez, Peter Peer, Vitomir Struc |
IJCB | 26 |
| 2023 | DFGC-VRA: DeepFake Game Competition on Visual Realism AssessmentabstractThis paper presents the summary report on the DeepFake Game Competition on Visual Realism Assessment (DFGC-VRA). Deep-learning based face-swap videos, also known as deepfakes, are becoming more and more realistic and deceiving. The malicious usage of these face-swap videos has caused wide concerns. There is a ongoing deepfake game between its creators and detectors, with the human in the loop. The research community has been focusing on the automatic detection of these fake videos, but the assessment of their visual realism, as perceived by human eyes, is still an unexplored dimension. Visual realism assessment, or VRA, is essential for assessing the potential impact that may be brought by a specific face-swap video, and it is also useful as a quality metric to compare different face-swap methods. This is the third edition of DFGC competitions, which focuses on the new visual realism assessment topic, different from previous ones that compete creators versus detectors. With this competition, we conduct a comprehensive study of the SOTA performance on the new task. We also release our MindSpore codes to further facilitate research in this field (https://github.com/bomb2peng/DFGC-VRA-benckmark). Bo Peng 0002, Xianyun Sun, Caiyong Wang, Wei Wang 0025, Jing Dong 0003, Zhenan Sun, Rongyu Zhang, Heng Cong, Lingzhi Fu, Yusheng Zhang, Boyuan Liu, Luka Dragar, Borut Batagelj, Peter Peer, Vitomir Struc, Xinghui Zhou, Kunlin Liu, Wenxiu Diao |
IJCB | 18 |
| 2023 | SeeABLE: Soft Discrepancies and Bounded Contrastive Learning for Exposing DeepfakesabstractModern deepfake detectors have achieved encouraging results, when training and test images are drawn from the same data collection. However, when these detectors are applied to images produced with unknown deepfake-generation techniques, considerable performance degradations are commonly observed. In this paper, we propose a novel deepfake detector, called SeeABLE, that formalizes the detection problem as a (one-class) out-of-distribution detection task and generalizes better to unseen deepfakes. Specifically, SeeABLE first generates local image perturbations (referred to as soft-discrepancies) and then pushes the perturbed faces towards predefined prototypes using a novel regression-based bounded contrastive loss. To strengthen the generalization performance of SeeABLE to unknown deepfake types, we generate a rich set of soft discrepancies and train the detector: (i) to localize, which part of the face was modified, and (ii) to identify the alteration type. To demonstrate the capabilities of SeeABLE, we perform rigorous experiments on several widely-used deepfake datasets and show that our model convincingly outperforms competing state-of-the-art detectors, while exhibiting highly encouraging generalization capabilities. The source code for SeeABLE is available from: https://github.com/anonymous-author-sub/seeable. Nicolas Larue, Ngoc-Son Vu, Vitomir Struc, Peter Peer, Vassilis Christophides |
ICCV | 4 |
| 2023 | Occluded thermal face recognition using BoCNN and radial derivative Gaussian feature descriptor
Satish Kumar Singh, Peter Peer |
Image Vis. Comput. | 3 |
| 2023 | Face deidentification with controllable privacy protectionabstractPrivacy protection has become a crucial concern in today’s digital age. Particularly sensitive here are facial images, which typically not only reveal a person’s identity, but also other sensitive personal information. To address this problem, various face deidentification techniques have been presented in the literature. These techniques try to remove or obscure personal information from facial images while still preserving their usefulness for further analysis. While a considerable amount of work has been proposed on face deidentification, most state-of-the-art solutions still suffer from various drawbacks, and (a) deidentify only a narrow facial area, leaving potentially important contextual information unprotected, (b) modify facial images to such degrees, that image naturalness and facial diversity is suffering in the deidentify images, (c) offer no flexibility in the level of privacy protection ensured, leading to suboptimal deployment in various applications, and (d) often offer an unsatisfactory trade-off between the ability to obscure identity information, quality and naturalness of the deidentified images, and sufficient utility preservation. In this paper, we address these shortcomings with a novel controllable face deidentification technique that balances image quality, identity protection, and data utility for further analysis. The proposed approach utilizes a powerful generative model (StyleGAN2), multiple auxiliary classification models, and carefully designed constraints to guide the deidentification process. The approach is validated across four diverse datasets (CelebA-HQ, RaFD, XM2VTS, AffectNet) and in comparison to 7 state-of-the-art competitors. The results of the experiments demonstrate that the proposed solution leads to: (a) a considerable level of identity protection, (b) valuable preservation of data utility, (c) sufficient diversity among the deidentified faces, and (d) encouraging overall performance. Blaz Meden, Manfred Gonzalez-Hernandez, Peter Peer, Vitomir Struc |
Image Vis. Comput. | 3 |
| 2023 | Exploring Bias in Sclera Segmentation Models: A Group Evaluation ApproachabstractBias and fairness of biometric algorithms have been key topics of research in recent years, mainly due to the societal, legal and ethical implications of potentially unfair decisions made by automated decision-making models. A considerable amount of work has been done on this topic across different biometric modalities, aiming at better understanding the main sources of algorithmic bias or devising mitigation measures. In this work, we contribute to these efforts and present the first study investigating bias and fairness of sclera segmentation models. Although sclera segmentation techniques represent a key component of sclera-based biometric systems with a considerable impact on the overall recognition performance, the presence of different types of biases in sclera segmentation methods is still underexplored. To address this limitation, we describe the results of a group evaluation effort (involving seven research groups), organized to explore the performance of recent sclera segmentation models within a common experimental framework and study performance differences (and bias), originating from various demographic as well as environmental factors. Using five diverse datasets, we analyze seven independently developed sclera segmentation models in different experimental configurations. The results of our experiments suggest that there are significant differences in the overall segmentation performance across the seven models and that among the considered factors, ethnicity appears to be the biggest cause of bias. Additionally, we observe that training with representative and balanced data does not necessarily lead to less biased results. Finally, we find that in general there appears to be a negative correlation between the amount of bias observed (due to eye color, ethnicity and acquisition device) and the overall segmentation performance, suggesting that advances in the field of semantic segmentation may also help with mitigating bias. Matej Vitek, Abhijit Das 0001, Diego Rafael Lucio, Luiz Antonio Zanlorensi, David Menotti, Jalil Nourmohammadi-Khiarak, Mohsen Akbari Shahpar, Meysam Asgari-Chenaghlu, Farhang Jaryani, Juan E. Tapia, Andres Valenzuela, Caiyong Wang, Yunlong Wang 0003, Zhaofeng He 0001, Zhenan Sun, Fadi Boutros, Naser Damer, Jonas Henry Grebe, Arjan Kuijper, Kiran B. Raja, Gourav Gupta, Georgios Zampoukis, Lazaros T. Tsochatzidis, Ioannis Pratikakis, S. V. Aruna Kumar, B. S. Harish, Umapada Pal 0001, Peter Peer, Vitomir Struc |
IEEE Trans. Inf. Forensics Secur. | 28 |
| 2022 | SYN-MAD 2022: Competition on Face Morphing Attack Detection Based on Privacy-aware Synthetic Training DataabstractThis paper presents a summary of the Competition on Face Morphing Attack Detection Based on Privacy-aware Synthetic Training Data (SYN-MAD) held at the 2022 In-ternational Joint Conference on Biometrics (IJCB 2022). The competition attracted a total of 12 participating teams, both from academia and industry and present in 11 differ-ent countries. In the end, seven valid submissions were submitted by the participating teams and evaluated by the organizers. The competition was held to present and at-tract solutions that deal with detecting face morphing at-tacks while protecting people's privacy for ethical and le-gal reasons. To ensure this, the training data was limited to synthetic data provided by the organizers. The submitted solutions presented innovations that led to out-performing the considered baseline in many experimental settings. The evaluation benchmark is now available at: https://github.com/marcohuber/SYN-MAD-2022. Marco Huber, Fadi Boutros, Anh Thi Luu, Kiran B. Raja, Ramachandra Raghavendra, Naser Damer, Pedro C. Neto, Tiago Gonçalves 0001, Ana Filipa Sequeira, Jaime S. Cardoso 0001, João Tremoço, Miguel Lourenço, Sergio Serra, Eduardo Cermeño, Marija Ivanovska, Borut Batagelj, Andrej Kronovsek, Peter Peer, Vitomir Struc |
IJCB | 18 |
| 2022 | BiOcularGAN: Bimodal Synthesis and Annotation of Ocular ImagesabstractCurrent state-of-the-art segmentation techniques for ocular images are critically dependent on large-scale annotated datasets, which are labor-intensive to gather and often raise privacy concerns. In this paper, we present a novel framework, called BiOcularGAN, capable of generating synthetic large-scale datasets of photorealistic (visible light and near-infrared) ocular images, together with corresponding segmentation labels to address these issues. At its core, the framework relies on a novel Dual-Branch StyleGAN2 (DB-StyleGAN2) model that facilitates bimodal image generation, and a Semantic Mask Generator (SMG) component that produces semantic annotations by exploiting latent features of the DB-StyleGAN2 model. We evaluate BiOcularGAN through extensive experiments across five diverse ocular datasets and analyze the effects of bi-modal data generation on image quality and the produced annotations. Our experimental results show that BiOcularGAN is able to produce high-quality matching bimodal images and annotations (with minimal manual intervention) that can be used to train highly competitive (deep) segmentation models (in a privacy aware-manner) that perform well across multiple real-world datasets. The source code for the BiOcularGAN framework is publicly available at https://github.com/dariant/BiOcularGAN. Darian Tomasevic, Peter Peer, Vitomir Struc |
IJCB | 2 |
| 2022 | FaceQAN: Face Image Quality Assessment Through Adversarial Noise ExplorationabstractRecent state-of-the-art face recognition (FR) approaches have achieved impressive performance, yet unconstrained face recognition still represents an open problem. Face image quality assessment (FIQA) approaches aim to estimate the quality of the input samples that can help provide information on the confidence of the recognition decision and eventually lead to improved results in challenging scenarios. While much progress has been made in face image quality assessment in recent years, computing reliable quality scores for diverse facial images and FR models remains challenging. In this paper, we propose a novel approach to face image quality assessment, called FaceQAN, that is based on adversarial examples and relies on the analysis of adversarial noise which can be calculated with any FR model learned by using some form of gradient descent. As such, the proposed approach is the first to link image quality to adversarial attacks. Comprehensive (cross-model as well as model-specific) experiments are conducted with four benchmark datasets, i.e., LFW, CFP–FP, XQLFW and IJB–C, four FR models, i.e., CosFace, ArcFace, CurricularFace and ElasticFace, and in comparison to seven state-of-the-art FIQA methods to demonstrate the performance of FaceQAN. Experimental results show that FaceQAN achieves competitive results, while exhibiting several desirable characteristics. The source code for FaceQAN is available at https://github.com/LSIbabnikz/FaceQAN. Ziga Babnik, Peter Peer, Vitomir Struc |
ICPR | 2 |
| 2022 | C-VTON: Context-Driven Image-Based Virtual Try-On NetworkabstractImage-based virtual try-on techniques have shown great promise for enhancing the user-experience and improving customer satisfaction on fashion-oriented e-commerce platforms. However, existing techniques are currently still limited in the quality of the try-on results they are able to produce from input images of diverse characteristics. In this work, we propose a Context-Driven Virtual Try-On Network (C-VTON) that addresses these limitations and convincingly transfers selected clothing items to the target subjects even under challenging pose configurations and in the presence of self-occlusions. At the core of the C-VTON pipeline are: (i) a geometric matching procedure that efficiently aligns the target clothing with the pose of the person in the input images, and (ii) a powerful image generator that utilizes various types of contextual information when synthesizing the final try-on result. C-VTON is evaluated in rigorous experiments on the VITON and MPV datasets and in comparison to state-of-the-art techniques from the literature. Experimental results show that the proposed approach is able to produce photo-realistic and visually convincing results and significantly improves on the existing state-of-the-art. Benjamin Fele, Ajda Lampe, Peter Peer, Vitomir Struc |
WACV | 3 |
| 2022 | Fingermark quality assessment framework with classic and deep learning ensemble modelsabstractThe quality assessment of fingermarks (latent fingerprints) is an essential part of a forensic investigation. It indicates how valuable the fingermarks are as forensic evidence, it determines how they should be further processed, and it correlates with the likelihood of successful identification, i.e., finding a matching fingerprint in a reference database. Since the environments in which fingermarks are found are not controlled, this task proves challenging even with modern machine learning solutions. In this work, we propose a predictive framework for automated fingermark quality assessment (AFQA). With this iteration of AFQA, we bridge the gap between the classic machine learning approach with handcrafted features and the modern deep learning paradigm, evaluate the advantages and disadvantages of these methodologies, and provide the rationale and direction for future development of AFQA methods. We present a significantly improved AFQA toolbox and provide a quality aggregation method capable of fusing together multiple predicted quality values from an ensemble of quality assessment models. The proposed ensemble approach provides improved prediction performance while reducing processing time compared to existing state-of-the-art solutions. Tim Oblak, Rudolf Haraksim, Peter Peer, Laurent Beslay |
Knowl. Based Syst. | 3 |
| 2021 | NIR Iris Challenge Evaluation in Non-cooperative Environments: Segmentation and LocalizationabstractFor iris recognition in non-cooperative environments, iris segmentation has been regarded as the first most important challenge still open to the biometric community, affecting all downstream tasks from normalization to recognition. In recent years, deep learning technologies have gained significant popularity among various computer vision tasks and also been introduced in iris biometrics, especially iris segmentation. To investigate recent developments and attract more interest of researchers in the iris segmentation method, we organized the 2021 NIR Iris Challenge Evaluation in Non-cooperative Environments: Segmentation and Localization (NIR-ISL 2021) at the 2021 International Joint Conference on Biometrics (IJCB 2021). The challenge was used as a public platform to assess the performance of iris segmentation and localization methods on Asian and African NIR iris images captured in non-cooperative environments. The three best-performing entries achieved solid and satisfactory iris segmentation and localization results in most cases, and their code and models have been made publicly available for reproducibility research. Caiyong Wang, Yunlong Wang 0003, Kunbo Zhang, Jawad Muhammad, Qi Zhang 0015, Qichuan Tian, Zhaofeng He 0001, Zhenan Sun, Tianbao Liu, Wei Yang 0006, Dongliang Wu, Yingfeng Liu, Ruiye Zhou, Huihai Wu, Junbao Wang, Wantong Xiong, Xueyu Shi, Shao Zeng, Peihua Li, Huijie Wu, Xinhui Zhang, Menghan Zhang, Fadi Boutros, Naser Damer, Arjan Kuijper, Juan E. Tapia, Andres Valenzuela, Christoph Busch 0001, Gourav Gupta, Kiran B. Raja, Xi Wu 0004, Xiaojie Li 0001, Jingfu Yang, Hongyan Jing, Xin Wang 0045, Bin Kong 0001, Youbing Yin, Qi Song 0001, Siwei Lyu, Shu Hu 0001, Leon Premk, Matej Vitek, Vitomir Struc, Peter Peer, Jalil Nourmohammadi-Khiarak, Farhang Jaryani, Samaneh Salehi Nasab, Seyed Naeim Moafinejad, Yasin Amini, Morteza Noshad |
IJCB | 57 |
| 2021 | Privacy-Enhancing Face Biometrics: A Comprehensive SurveyabstractBiometric recognition technology has made significant advances over the last decade and is now used across a number of services and applications. However, this widespread deployment has also resulted in privacy concerns and evolving societal expectations about the appropriate use of the technology. For example, the ability to automatically extract age, gender, race, and health cues from biometric data has heightened concerns about privacy leakage. Face recognition technology, in particular, has been in the spotlight, and is now seen by many as posing a considerable risk to personal privacy. In response to these and similar concerns, researchers have intensified efforts towards developing techniques and computational models capable of ensuring privacy to individuals, while still facilitating the utility of face recognition technology in several application scenarios. These efforts have resulted in a multitude of privacy-enhancing techniques that aim at addressing privacy risks originating from biometric systems and providing technological solutions for legislative requirements set forth in privacy laws and regulations, such as GDPR. The goal of this overview paper is to provide a comprehensive introduction into privacy-related research in the area of biometrics and review existing work on Biometric Privacy-Enhancing Techniques (B-PETs) applied to face biometrics. To make this work useful for as wide of an audience as possible, several key topics are covered as well, including evaluation strategies used with B-PETs, existing datasets, relevant standards, and regulations and critical open issues that will have to be addressed in the future. Blaz Meden, Peter Rot, Philipp Terhörst, Naser Damer, Arjan Kuijper, Walter J. Scheirer, Arun Ross, Peter Peer, Vitomir Struc |
IEEE Trans. Inf. Forensics Secur. | 8 |
| 2020 | Learning privacy-enhancing face representations through feature disentanglementabstractConvolutional Neural Networks (CNNs) are today the de-facto standard for extracting compact and discriminative face representations (templates) from images in automatic face recognition systems. Due to the characteristics of CNN models, the generated representations typically encode a multitude of information ranging from identity to soft-biometric attributes, such as age, gender or ethnicity. However, since these representations were computed for the purpose of identity recognition only, the soft-biometric information contained in the templates represents a serious privacy risk. To mitigate this problem, we present in this paper a privacy-enhancing approach capable of suppressing potentially sensitive soft-biometric information in face representations without significantly compromising identity information. Specifically, we introduce a Privacy-Enhancing Face-Representation learning Network (PFRNet) that disentangles identity from attribute information in face representations and consequently allows to efficiently suppress soft-biometrics in face templates. We demonstrate the feasibility of PFRNet on the problem of gender suppression and show through rigorous experiments on the CelebA, Labeled Faces in the Wild (LFW) and Adience datasets that the proposed disentanglement-based approach is highly effective and improves significantly on the existing state-of-the-art. Blaz Bortolato, Marija Ivanovska, Peter Rot, Janez Krizaj, Philipp Terhörst, Naser Damer, Peter Peer, Vitomir Struc |
FG | 7 |
| 2020 | SSBC 2020: Sclera Segmentation Benchmarking Competition in the Mobile EnvironmentabstractThe paper presents a summary of the 2020 Sclera Segmentation Benchmarking Competition (SSBC), the 7th in the series of group benchmarking efforts centred around the problem of sclera segmentation. Different from previous editions, the goal of SSBC 2020 was to evaluate the performance of sclera-segmentation models on images captured with mobile devices. The competition was used as a platform to assess the sensitivity of existing models to i) differences in mobile devices used for image capture and ii) changes in the ambient acquisition conditions. 26 research groups registered for SSBC 2020, out of which 13 took part in the final round and submitted a total of 16 segmentation models for scoring. These included a wide variety of deep-learning solutions as well as one approach based on standard image processing techniques. Experiments were conducted with three recent datasets. Most of the segmentation models achieved relatively consistent performance across images captured with different mobile devices (with slight differences across devices), but struggled most with low-quality images captured in challenging ambient conditions, i.e., in an indoor environment and with poor lighting. Matej Vitek, Abhijit Das 0001, Yann Pourcenoux, Alexandre Missler, C. Paumier, Sumanta Das, Ishita De Ghosh, Diego Rafael Lucio, Luiz Antonio Zanlorensi, David Menotti, Fadi Boutros, Naser Damer, Jonas Henry Grebe, Arjan Kuijper, Junxing Hu, Yong He 0009, Caiyong Wang, Yunlong Wang 0003, Zhenan Sun, Dailé Osorio Roig, Christian Rathgeb, Christoph Busch 0001, Juan E. Tapia, Andres Valenzuela, Georgios Zampoukis, Lazaros T. Tsochatzidis, Ioannis Pratikakis, Sabari Nathan, R. Suganya 0001, Vineet Mehta, Abhinav Dhall, Kiran B. Raja, Gourav Gupta, Jalil Nourmohammadi-Khiarak, Mohsen Akbari-Shahper, Farhang Jaryani, Meysam Asgari-Chenaghlu, Ritesh Vyas, Sristi Dakshit, Peter Peer, Umapada Pal 0001, Vitomir Struc |
IJCB | 41 |
| 2020 | Evaluation and analysis of ear recognition models: performance, complexity and resource requirements
Ziga Emersic, Blaz Meden, Peter Peer, Vitomir Struc |
Neural Comput. Appl. | 3 |
| 2020 | Simultaneous multi-descent regression and feature learning for facial landmarking in depth imagesabstractAbstract Face alignment (or facial landmarking) is an important task in many face-related applications, ranging from registration, tracking, and animation to higher-level classification problems such as face, expression, or attribute recognition. While several solutions have been presented in the literature for this task so far, reliably locating salient facial features across a wide range of posses still remains challenging. To address this issue, we propose in this paper a novel method for automatic facial landmark localization in 3D face data designed specifically to address appearance variability caused by significant pose variations. Our method builds on recent cascaded regression-based methods to facial landmarking and uses a gating mechanism to incorporate multiple linear cascaded regression models each trained for a limited range of poses into a single powerful landmarking model capable of processing arbitrary-posed input data. We develop two distinct approaches around the proposed gating mechanism: (1) the first uses a gated multiple ridge descent mechanism in conjunction with established (hand-crafted) histogram of gradients features for face alignment and achieves state-of-the-art landmarking performance across a wide range of facial poses and (2) the second simultaneously learns multiple-descent directions as well as binary features that are optimal for the alignment tasks and in addition to competitive landmarking results also ensures extremely rapid processing. We evaluate both approaches in rigorous experiments on several popular datasets of 3D face images, i.e., the FRGCv2 and Bosphorus 3D face datasets and image collections F and G from the University of Notre Dame. The results of our evaluation show that both approaches compare favorably to the state-of-the-art, while exhibiting considerable robustness to pose variations. Janez Krizaj, Peter Peer, Vitomir Struc, Simon Dobrisek |
Neural Comput. Appl. | 2 |
| 2020 | A comprehensive investigation into sclera biometrics: a novel dataset and performance study
Matej Vitek, Peter Rot, Vitomir Struc, Peter Peer |
Neural Comput. Appl. | 4 |
| 2019 | Frame-based classification for cross-speed gait recognition
Jure Kovac, Vitomir Struc, Peter Peer |
Multim. Tools Appl. | 3 |
| 2017 | Training Convolutional Neural Networks with Limited Training Data for Ear Recognition in the WildabstractIdentity recognition from ear images is an active field of research within the biometric community. The ability to capture ear images from a distance and in a covert manner makes ear recognition technology an appealing choice for surveillance and security applications as well as related application domains. In contrast to other biometric modalities, where large datasets captured in uncontrolled settings are readily available, datasets of ear images are still limited in size and mostly of laboratory-like quality. As a consequence, ear recognition technology has not benefited yet from advances in deep learning and convolutionalneural networks (CNNs) and is still lacking behind other modalities that experienced significant performance gains owing to deep recognition technology. In this paper we address this problem and aim at building a CNN-based ear recognition model. We explore different strategies towards model training with limited amounts of training data and show that by selecting an appropriate model architecture, using aggressive data augmentation and selective learning on existing (pre-trained) models, we are able to learn an effective CNN·based model using a little more than 1300training images. The result of our work is the first CNN·based approach to ear recognition that is also made publicly available to the research community. With our model we are able to improve on the rank one recognition rate of the previous state-of-the-art by more than 25% on a challenging dataset of ear images captured from the web (a.k.a, in the wild). Ziga Emersic, Dejan Stepec, Vitomir Struc, Peter Peer |
FG | 4 |
| 2017 | SSERBC 2017: Sclera segmentation and eye recognition benchmarking competitionabstractThis paper summarises the results of the Sclera Segmentation and Eye Recognition Benchmarking Competition (SSERBC 2017). It was organised in the context of the International Joint Conference on Biometrics (IJCB 2017). The aim of this competition was to record the recent developments in sclera segmentation and eye recognition in the visible spectrum (using iris, sclera and peri-ocular, and their fusion), and also to gain the attention of researchers on this subject. In this regard, we have used the Multi-Angle Sclera Dataset (MASD version 1). It is comprised of2624 images taken from both the eyes of 82 identities. Therefore, it consists of images of 164 (82×2) eyes. A manual segmentation mask of these images was created to baseline both tasks. Precision and recall based statistical measures were employed to evaluate the effectiveness of the segmentation and the ranks of the segmentation task. Recognition accuracy measure has been employed to measure the recognition task. Manually segmented sclera, iris and peri-ocular regions were used in the recognition task. Sixteen teams registered for the competition, and among them, six teams submitted their algorithms or systems for the segmentation task and two of them submitted their recognition algorithm or systems. The results produced by these algorithms or systems reflect current developments in the literature of sclera segmentation and eye recognition, employing cutting edge techniques. The MASD version 1 dataset with some of the ground truth will be freely available for research purposes. The success of the competition also demonstrates the recent interests of researchers from academia as well as industry on this subject. Abhijit Das 0001, Umapada Pal 0001, Miguel A. Ferrer, Michael Blumenstein, Dejan Stepec, Peter Rot, Ziga Emersic, Peter Peer, Vitomir Struc, S. V. Aruna Kumar, B. S. Harish |
IJCB | 8 |
| 2017 | The unconstrained ear recognition challengeabstractIn this paper we present the results of the Unconstrained Ear Recognition Challenge (UERC), a group benchmarking effort centered around the problem of person recognition from ear images captured in uncontrolled conditions. The goal of the challenge was to assess the performance of existing ear recognition techniques on a challenging large-scale dataset and identify open problems that need to be addressed in the future. Five groups from three continents participated in the challenge and contributed six ear recognition techniques for the evaluation, while multiple baselines were made available for the challenge by the UERC organizers. A comprehensive analysis was conducted with all participating approaches addressing essential research questions pertaining to the sensitivity of the technology to head rotation, flipping, gallery size, large-scale recognition and others. The top performer of the UERC was found to ensure robust performance on a smaller part of the dataset (with 180 subjects) regardless of image characteristics, but still exhibited a significant performance drop when the entire dataset comprising 3,704 subjects was used for testing. Ziga Emersic, Dejan Stepec, Vitomir Struc, Peter Peer, Anjith George, Adil M. Ahmad, Elshibani Omar, Terrance E. Boult, Reza Safdari, Stefanos Zafeiriou, Doggucan Yaman, Fevziye Irem Eyiokur, Hazim Kemal Ekenel |
IJCB | 4 |
| 2017 | Face deidentification with generative deep neural networksabstractFace deidentification is an active topic amongst privacy and security researchers. Early deidentification methods relying on image blurring or pixelisation have been replaced in recent years with techniques based on formal anonymity models that provide privacy guaranties and retain certain characteristics of the data even after deidentification. The latter aspect is important, as it allows the deidentified data to be used in applications for which identity information is irrelevant. In this work, the authors present a novel face deidentification pipeline, which ensures anonymity by synthesising artificial surrogate faces using generative neural networks (GNNs). The generated faces are used to deidentify subjects in images or videos, while preserving non‐identity‐related aspects of the data and consequently enabling data utilisation. Since generative networks are highly adaptive and can utilise diverse parameters (pertaining to the appearance of the generated output in terms of facial expressions, gender, race etc.), they represent a natural choice for the problem of face deidentification. To demonstrate the feasibility of the authors’ approach, they perform experiments using automated recognition tools and human annotators. Their results show that the recognition performance on deidentified images is close to chance, suggesting that the deidentification process based on GNNs is effective. Blaz Meden, Refik Can Malli, Sebastjan Fabijan, Hazim Kemal Ekenel, Vitomir Struc, Peter Peer |
IET Signal Process. | 6 |
| 2017 | Ear recognition: More than a survey
Ziga Emersic, Vitomir Struc, Peter Peer |
Neurocomputing | 3 |
| 2006 | Where physically is the optical center?
Peter Peer, Franc Solina |
Pattern Recognit. Lett. | 1 |
| 2005 | Estimation of a fluorescent lamp spectral distribution for color image in machine vision
Luis Galo Corzo, Jose Peñaranda, Peter Peer |
Mach. Vis. Appl. | 3 |
| 2004 | 15 seconds of fame: an interactive, computer-vision based art installationabstract"15 seconds of fame" is an interactive installation which every 15 seconds generates a newpop-art portrait of a randomly selected person from the audience. The installation was inspired by Andy Warhol's ironical statement that "In the future everybody will be famous for 15 minutes". The installation detects human faces in digital images of people who are standing in front of the installation. Pop-art portraits are then generated from randomly chosen faces in the audience by applying randomlyselected filters. These portraits are shown in 15 second intervals on the flat-panel computer monitor which is framed as a painting. Electronic copies of each displayed portrait can be ordered by e-mail. Borut Batagelj, Franc Solina, Peter Peer |
ACM Multimedia | 3 |
| 2003 | Towards a Real Time Panoramic Depth Sensor
Peter Peer, Franc Solina |
CAIP | 1 |
| 2002 | 15 seconds of fame - an interactive, computer-vision based art installationabstract"15 seconds of fame" is an interactive art installation, which elevates the face of a randomly selected gallery visitor for 15 seconds into a "work of art". The installation was inspired by Andy Warhol's statement that "In the future everybody will be world famous for fifteen minutes" as well as by the pop-art style of his works. The installation consists of a computer with a flat-panel monitor, a digital camera and a proprietary software that can detect human faces in images and graphically transform them. In this paper we present the technical background of the installation, in particular, how computer vision techniques were applied in this art installation. Franc Solina, Peter Peer, Borut Batagelj, Samo Juvan |
ICARCV | 2 |
| 2002 | Panoramic Depth Imaging: Single Standard Camera Approach
Peter Peer, Franc Solina |
Int. J. Comput. Vis. | 1 |