Niklas Deckers

Universität Kassel

The prerequisite of many approaches to authorship analysis is a representation of writing style. But despite decades of research, it still remains unclear to what extent commonly used and widely accepted representations like character trigram frequencies actually represent an author's writing style, in contrast to more domain-specific style compone...

There are now a variety of methods and devices for deriving 3D information, e.g. binocular camera (stereo) systems and methods of the class "shape from X". In addition, there are modern recording technologies that simultaneously measure gray scale values and distance (range cameras, TOF cameras). Many of these methods are available through low-cost...

Das Ableiten von 3D-Informationen aus Bilddaten stellt in der Regel besondere Anforderungen an die verwendete Kamerahardware. Es existieren jedoch Ansätze, die aus einem einzelnen Kamerabild 3D-Daten des Skeletts bekannter Objekte extrahieren können: Auf Basis neuronaler Netze erfolgt die Extraktion von Features, welche den Skelettpunkten zugeordne...

Prompt engineering is still the primary way for users of generative text-to-image models to manipulate generated images in a targeted way. Based on treating the model as a continuous function and by passing gradients between the image space and the prompt embedding space, we propose and analyze a new method to directly manipulate the embedding of a...

We have built TIREx, the information retrieval experiment platform, to promote standardized, reproducible, scalable, and blinded retrieval experiments. Standardization is achieved through integration with PyTerrier's interfaces and compatibility with ir_datasets and ir_measures. Reproducibility and scalability are based on the underlying TIRA frame...

Representation-based retrieval models, so-called biencoders, estimate the relevance of a document to a query by calculating the similarity of their respective embeddings. Current state-of-the-art biencoders are trained using an expensive training regime involving knowledge distillation from a teacher model and batch-sampling. Instead of relying on...

Generative text-to-image models such as Stable Diffusion allow users to generate images based on a textual description, the prompt. Changing the prompt is still the primary means for the user to change a generated image as desired. However, changing the image by reformulating the prompt remains a difficult process of trial and error, which has led...

We integrate ir_datasets, ir_measures, and PyTerrier with TIRA in the Information Retrieval Experiment Platform (TIREx) to promote more standardized, reproducible, scalable, and even blinded retrieval experiments. Standardization is achieved when a retrieval approach implements PyTerrier's interfaces and the input and output of an experiment are co...

The text-to-image model Stable Diffusion has recently become very popular. Only weeks after its open source release, millions are experimenting with image generation. This is due to its ease of use, since all it takes is a brief description of the desired image to "prompt" the generative model. Rarely do the images generated for a new prompt immedi...

Web archives have grown to petabytes. In addition to providing invaluable background knowledge on many social and cultural developments over the last 30 years, they also provide vast amounts of training data for machine learning. To benefit from recent developments in Deep Learning, the use of web archives requires a scalable solution for their pro...

Language models demonstrate both quantitative improvement and new qualitative capabilities with increasing scale. Despite their potentially transformative impact, these new capabilities are as yet poorly characterized. In order to inform future research, prepare for disruptive new model capabilities, and ameliorate socially harmful effects, it is v...

We present a motion analysis framework for anomaly detection in the context of health monitoring in carp and koi ponds. We study recent advances in computer vision and deep learning for an automated motion assessment based on video streams and propose a specifically designed image acquisition system.

Pain estimation for horses is a tedious task since they are flight animals and tend to suppress pain specific behaviour. We obtained continuous video data of horse in different levels of pain, to evaluate their behaviour – while they were undergoing routine castration. During the whole time we regularly and manually evaluated the horses’ pain.

Over the last decades, various methods for three-dimensional detection of the environment have been developed and successfully used. This work considers classical stereo methods, which can determine depth information by the means of correspondence analysis on the basis of two pictures of a scene. Recently, neural networks have been used to solve co...

Over the last decades, various methods for three-dimensional detection of the environment have been developed and successfully used. This work considers classical stereo methods, which can determine depth information by the means of correspondence analysis on the basis of two pictures of a scene. Recently, neural networks have been used to solve co...

Forest inventory is an important topic in forestry and a digital solution which works on the basis of tree images is looked for. Implementing a system which automatically classifies tree species is the overall goal. In this paper the implementation of a convolutional neural net for solving this classification problem is executed and evaluated. The...

This paper focuses on the automated analysis of motion patterns for relating an individual's behaviour with its pain experience. Reliable, automated behaviour analysis can improve video observation considerably, i.e. by lessening the work load of human operators, decreasing human error and by increasing anonymity and privacy. Possible applications...

Das Ableiten von 3D-Informationen aus Bilddaten stellt in der Regel besondere Anforderungen an die verwendete Kamerahardware. Es existieren jedoch Ansätze, die aus einem einzelnen Kamerabild 3D-Daten des Skeletts bekannter Objekte extrahieren können. Auf Basis neuronaler Netze erfolgt die Extraktion von Features, welche den Skelettpunkten zugeordne...

Low-resolution thermal infrared array sensors can be used to detect human bodies and motion. Segmentation and deriving features from the segmented shape using such devices remains challenging. For improving and testing segmentation results, a sensor fusion approach using a Kinect sensor can be used to automatically receive ground-truth data. After...

Video surveillance always had a negative connotation, among others because of the loss of privacy and because it may not automatically increase public safety. If it was able to detect atypical (i.e. dangerous) situations in real time, autonomously and anonymously, this could change. A prerequisite for this is an automatic detection of possibly dang...