Johannes Jordan

Learn More
A copy-move forgery is created by copying and pasting content within the same image, and potentially postprocessing it. In recent years, the detection of copy-move forgeries has become one of the most actively researched topics in blind image forensics. A considerable number of different algorithms have been proposed focusing on different types of(More)
The interaction among particles is a vital aspect of Particle Swarm Optimization. As such, it has a strong influence on the swarm's success. In this study various approaches regarding the particles' communication behavior and their relationship are examined, as well as possibilities to combine the approaches. A new variant of the popular FIPS algorithm, the(More)
We propose a new method for performing edge detection in multi-spectral images based on the self-organizing map (SOM) concept. Previously, 1-dimensional or 2-dimensional SOMs were trained to provide a linear mapping of high-dimensional multispectral vectors. Then, edge detection was applied on that mapping. However, the 1-dimensional SOM may not converge on(More)
The dichromatic reflectance model has been successfully applied on different tasks in color research, such as color constancy and highlight or shadow segmentation. In its original version, it incorporates only one direct illuminant. In this work, we analyze a recently published model, the Bi-Illuminant Dichromatic Reflectance Model (BIDR) proposed by(More)
Mean shift clustering and its recent variants are a viable and popular image segmentation tool. In this paper we investigate mean shift segmentation on multispectral and hyperspectral images and propose three new algorithms. First, we improve segmentation performance by running mean shift on the spectral gradient. At the same time, we adapt a popular(More)
For a variety of multi-sensor imaging systems, there is a strong need for resolution enhancement. In this paper, we propose a unified method for single-image upsampling and multi-frame super-resolution of multi-channel images. We derive our algorithm from a Bayesian model that is formulated by a novel image prior to exploit sparsity of individual channels(More)
In recent years, graph-based methods have had a significant impact on image segmentation. They are especially noteworthy for supervised segmentation, where the user provides task-specific foreground and background seeds. We adapt the power watershed framework to multispectral and hyperspectral image data and incorporate similarity measures from the field of(More)
In this paper we propose a method for learning the materials in a scene in an unsupervised manner making use of imaging spectroscopy data. Here, we view the input image spectra as a data point on a manifold which corresponds to a node in a graph whose vertices correspond to a set of parameters that should be inferred using the Expectation Maximisation (EM)(More)
  • 1