Fotini Fotopoulou

  • Citations Per Year
Learn More
In this work, the idea of key frames extraction from single shots in video sequences is presented. The method is implemented by an efficient two-step algorithm, which is classified neither to clustering nor to temporal variations based techniques. In the first step, an MST (minimal spanning tree) graph is constructed, where each node is associated to a(More)
In this paper, a new shape decomposition method named Visibility Shape Decomposition (VSD) is presented. Inspired from an idealization of the visibility matrix having a block diagonal form, the definition of a neighborhood based visibility graph is proposed and a two step iterative algorithm for its transformation into a block diagonal form, that can be(More)
In this paper, the shape decomposition problem is addressed as a solution of an appropriately constrained Nonnegative Matrix Factorization Problem (NMF). Inspired from an idealization of the visibility matrix having a block diagonal form, special requirements while formulating the NMF problem are taken into account. Starting from a contaminated observation(More)
In this work, we propose a unified approach for video summarization based on the analysis of the video structure. The method originates from a data learning technique that uses the membership values produced by an over-partitioning mode of the FCM algorithm to find the connection strength between the resulting set of prototype centers. The final clustering(More)
A novel method for shape analysis and similarity measurement is introduced based on a time series matching approach. It applies to shapes represented through one-dimensional signals and has as objectives to utilize efficiently the provided information and to optimize the shape matching process. The new technique is tested on boundaries from leaf images,(More)
In the present paper a novel graph-based approach to the shape decomposition problem is addressed. The shape is appropriately transformed into a visibility graph enriched with local neighborhood information. A two-step diffusion process is then applied to the visibility graph that efficiently enhances the information provided, thus leading to a more robust(More)
2-D shape recognition and content-based image retrieval using the boundary information as a 1-D time series is a common way of addressing the shape-matching problem. A significant factor for successful object identification is insensitivity to basic shape deformations, such as scaling, shifting, rotation, partial distortions etc. In this paper, a method for(More)