Person Re-Identification by Discriminative Selection in Video Ranking

Current person re-identification (ReID) methods typically rely on single-frame imagery features, whilst ignoring space-time information from image sequences often available in the practical surveillance scenarios. Single-frame (single-shot) based visual appearance matching is inherently limited for person ReID in public spaces due to the challenging visual ambiguity and uncertainty arising from non-overlapping camera views where viewing condition changes can cause significant people appearance variations. In this work, we present a novel model to automatically select the most discriminative video fragments from noisy/incomplete image sequences of people from which reliable space-time and appearance features can be computed, whilst simultaneously learning a video ranking function for person ReID. Using the PRID2011, iLIDS-VID, and HDA+ image sequence datasets, we extensively conducted comparative evaluations to demonstrate the advantages of the proposed model over contemporary gait recognition, holistic image sequence matching and state-of-the-art single-/multi-shot ReID methods

Person Re-identification by Video Ranking

Abstract. Current person re-identification (re-id) methods typically rely on single-frame imagery features, and ignore space-time information from image sequences. Single-frame (single-shot) visual appearance matching is inherently limited for person re-id in public spaces due to visual ambiguity arising from non-overlapping camera views where viewpoint and lighting changes can cause significant appearance variation. In this work, we present a novel model to automatically select the most discriminative video fragments from noisy image sequences of people where more reliable space-time features can be extracted, whilst simultaneously to learn a video ranking function for person re-id. Also, we introduce a new image sequence re-id dataset (iLIDS-VID) based on the i-LIDS MCT benchmark data. Using the iLIDS-VID and PRID 2011 sequence re-id datasets, we extensively conducted comparative evaluations to demonstrate the advantages of the proposed model over contemporary gait recognition, holistic image sequence matching and state-of-the-art singleshot/multi-shot based re-id methods.

Person re-identification by unsupervised video matching

This work was partially supported by National Basic Research Program of China (973 Project) 2012CB725405, the National Science and Technology Support Program (2014BAG03B01), National Natural Science Foundation China61273238, Beijing Municipal Science and Technology Project (D15110900280000), Tsinghua University Project (20131089307). Xiatian Zhu and Xiaolong Ma equally contributed to this work

Gait analysis advancements: rehabilitation value and new perspectives from forensic application

The clinical and rehabilitation value of gait analysis is remarkable and indisputable and poised to grow as technological advancements unfold. This article aims to shed light on the advances in how gait is assessed, enabling those who have suffered an injury impairing their motor skills to be diagnosed more accurately and efficiently as well as to compare the hallmarks of rehabilitative and forensic gait analysis. The authors have conducted an analysis of relevant papers (published between 1967 and 2020) from a medicolegal perspective, cited in PubMed, MEDLINE, Cochrane Library, EMBASE, and available recommendations for the legal application of such techniques. Moreover, considering the use of gait analysis as a forensic tool, this study broadens the scope of research by including search engines, legal databases, and court filings (DeJure, Lexis Nexis, Justia) between 2000 and 2022. The instrumental assessment of movement (Gait Analysis) has come to constitute an essential analytical tool for the biomedical sector to objectively and accurately assess human movement and posture. The article is also aimed at elaborating differences and similarities between clinical and forensic gait analysis. When it comes to the forensic applicability of gait analysis and its evidentiary value, however, there is a pressing need for a review of its scientific basis. Therefore, it is necessary to conduct a thorough evaluation of its use in legal practice, as stressed in scientific literature and surveys. It is of utmost importance to highlight the procedural and assessment standards currently applied to forensic gait analysis, to evaluate its strengths and weaknesses, and to achieve standardized guidelines based on broad scientific consensus

Gaming passion contributes to the definition and identification of problematic gaming

Even if for most people playing video games is a healthy leisure activity, a minority of vulnerable users present an excessive use associated to negative consequences (e.g., psychosocial maladjustment, sleep interference) and functional impairment. The current study first aims to identify psychological factors that contribute to discriminate highly involved (but healthy) gamers from problematic gamers. For that purpose, we used a cluster analysis approach to identify different groups of gamers based on their profiles of passion towards gaming (using the Dualistic Model of Passion). Another objective of the present study is to explore, using supervised machine-learning, how gaming disorder symptoms, assessed within the substance use disorder framework (e.g., tolerance, withdrawal), might be linked to harmonious and/or an obsessive passion for gaming. Three distinct clusters of gamers were identified based on their passion profiles, including risky gamers, engaged gamers, and casual gamers. Supervised machine-learning algorithms identified that specific gaming disorder symptoms (salience, mood modification, tolerance, low level of conflict) were predominantly related to harmonious passion, whereas others (withdrawal, high level of conflict, relapse) were more directly related to obsessive passion. Our results support the relevance of person-centered approaches to the treatment of problematic gaming

Privacy Law Disparities between the United States and the European Union

Data is the world’s most valuable resource today. In the 21st century, big data has overtaken the world’s commonly known large industries to become one of the most sought after markets, and companies pay to own this data (The Economist, 2017). Advertisements may have been targeted towards demographics such as race or sex in past years. However, in the digital age, the capability exists to push advertisements to the screens of specific users with known interests. This has been made possible, in part, by unregulated data collection practices across the globe, including in the United States and the European Union. Data collection practices, from the conception of the Internet until the present day, have been disregarding the consent of the user the data represents. This unregulated data collection practice was halted recently in the European Union with the passing of the General Data and Privacy Regulation. However, the practice remains of concern in the United States. This research aims to conduct a classic comparative analysis of the omnibus privacy laws of the United States and the European Union. The existing laws will be compared across the following variables: the right to be informed, right of access, right to rectification, right to erasure, right to restrict processing, right to data portability, and the right to object. Recommendations for improving the United States privacy legislation will be highlighted based on this comparative analysis

Government Analysis of Shed DNA Is a Search under the Fourth Amendment

This article addresses whether the Fourth Amendment is implicated when police surreptitiously collect and analyze a person’s involuntarily shed DNA. Law enforcement officers will often obtain shed or abandoned DNA samples from persons who they suspect have committed crimes, but lack sufficient evidence to arrest or detain such persons. When utilizing abandoned or shed DNA for criminal investigative purposes, there are two state actions which arguably trigger Fourth Amendment protection. First, the collection of the biological material which contains a person’s DNA might be considered a search under the amendment. Courts, however, have uniformly rejected this argument. For example, when police are interested in determining whether a suspect may be connected with an unsolved crime for which they collected a DNA sample from the crime scene, they will covertly obtain the suspect’s DNA from a fast-food wrapper or hair sample taken from a barber-shop floor. To date, judges have concluded that persons have discarded the DNA-laden cells obtained by police in these circumstances, and thus under Fourth Amendment law, retained no privacy interest in the item seized by police. Second, the analysis of the DNA sample might trigger Fourth Amendment safeguards. This second issue – whether the Fourth Amendment is implicated when police surreptitiously analyze a citizen’s involuntarily shed DNA – is the topic of my paper. Most recently, two state high courts, Maryland and Massachusetts, have rejected Fourth Amendment claims that government analysis of DNA samples lawfully obtained from persons constitutes a search under the Fourth Amendment. The Supreme Court denied certiorari in the Maryland case – Raynor v. Maryland, 99 A. 3d. 753 (Md. 2014), cert. denied, 135 S. Ct. 1509 (2015). The result in Raynor conflicts with a ruling of the United States Court of Appeals for the Fourth Circuit, the federal circuit in which Maryland sits. In United States v. Davis, 690 F. 3d 226 (4th Cir. 2012), the Fourth Circuit ruled that the analysis of a suspect’s DNA sample from clothing lawfully obtained by the police was a search. The Fourth Circuit explained that “analysis required to obtain a DNA profile . . . generally qualifies as a search, because an individual retains a legitimate expectation of privacy in the information obtained from the testing.” However, the Court has requested the Commonwealth of Massachusetts to file a reply to the certiorari petition filed in the Massachusetts case – Commonwealth v. Arzola, 26 N.E. 3d 185 (Mass. 2015). In concluding that analysis of a DNA sample does not constitute a search, both the Maryland and Massachusetts high courts relied heavily on the Supreme Court’s 2013 ruling in Maryland v. King, which held that where police have probable cause to arrest for a serious offense, “taking and analyzing a cheek swab of the arrestee’s DNA is, like fingerprinting and photographing, a legitimate police booking procedure that is reasonable under the Fourth Amendment.” Specifically, Part I of my article discusses whether analysis of abandoned DNA constitutes a search under the Fourth Amendment. Part II of the article considers a conflict in the Supreme Court’s cases when new technology or science gives law enforcement authorities enhanced capabilities to discover information arguably protected by the Fourth Amendment. In some cases, when deciding whether a search occurred, or the reasonableness of a challenged search, what a particular intrusion actually reveals matters little; what matters is the potential risk to privacy posed by new technology. In other cases, the fact that a particular intrusion has the potential to disclose highly personal data or massive amounts of information is constitutionally irrelevant. The only thing that matters is what was actually revealed by the intrusion. Finally, Part III of the article considers the implications of leaving the analysis of shed DNA unregulated by the Fourth Amendment