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Auflistung nach Autor:in "Labudde,Dirk"

1 - 3 von 3
  • Textdokument
    A frequentist estimation of duplicate probability as a baseline for person identification from image and video material using anthropometric measurements
    (INFORMATIK 2022, 2022) Heinke,Florian; Heuschkel,Marie-Luise; Labudde,Dirk
    Video and image material is becoming increasingly ubiquitous thus its potential as evidence in forensic investigations is growing. Once faces are hidden however, the value of surveillance footage is restricted unless there is another biometric trait that can be observed by camera such as linear body measurements. There is much biological evidence for human body proportions exhibiting much individual variation. Nevertheless, the probability of there being two individuals that match in their respective proportions ultimately determines its usability for the assignment, exclusion and even identification of persons in the forensic domain. This work is concerned with approaches for duplicate probability estimations derived from anthropometric measures. Here, we present a novel frequentist estimation using a dataset of 340 individuals and their respective anthropometric measurements. Drawing on density kernel estimations of measurement dissimilarity, we propose the duplicate probability to be in the order of 10^−15 to 10^−8.
  • Textdokument
    A pipeline for analysing image and video material in a forensic context with intelligent systems
    (INFORMATIK 2022, 2022) Preuß,Svenja; Labudde,Dirk
    Shows like CSI seem to convey a certain view on the capabilities of forensic science based on the vast progress of digitalisation and the new technology, that goes along with it. But those depictions can be misleading and hardly represent a realistic reflection of reality. Nevertheless, this representation influences the public view on digital forensic analysis. This phenomenon is also known as the CSI effect. To present a more realistic view on practices in digital forensics, we want to introduce typical image and video analysis methods used in tackling real life forensic challenges and point to their capabilities as well as their limits. In this context an important area is image and video enhancement. With methods such as Super Resolution, images can be scaled up, their corresponding resolution gets enhanced and image noise can be reduced. During the subsequent image analysis, methods ranging from purely cognitive analysis to extraction of raw pixel values and various semantic information from the image or video, utilizing AI frameworks, are used. This allows for example to detect and analyse faces up to whole people, as well as objects in images or videos.
  • Textdokument
    Recommendation of Query Terms for Colloquial Texts in Forensic Text Analysis
    (INFORMATIK 2022, 2022) Felser,Jenny; Xi,Jian; Demus,Christoph; Labudde,Dirk; Spranger,Michael
    Textual social media content and short messages have gained in importance as evidence in criminal investigations. Yet, the large number of textual data poses a great challenge for investigators. Even though text retrieval systems can assist in finding evidential messages, the success of the search still depends on entering appropriate search terms. However, for colloquial texts these are difficult to determine because one cannot be sure about what terms are used in the texts and might be of interest. Therefore, the aim is to develop a method that recommends keywords and searches phrases based on the underlying data. A particular challenge here is that the appropriate search terms are often non-obvious words that are not expected to be found in the data, but are particularly relevant. In total, four methods were evaluated for extracting and suggesting the most relevant terms and phrases using a real-life dataset. The best results were obtained with topic modeling considering syntagmatic relations.