VeranstaltungsortE.2.42Veranstalter Fakultät für Technische WissenschaftenBeschreibungWe present a comparison between AV1, HEVC and JEM. It reveals that professionally optimized AV1 encoding software is about 32 times as complex as the HEVC encoder software HM. Given the wide attention that AV1 receives and the plans of Google and Facebook to actually use AV1 in commercial environments, the complexity constraints endured during the HEVC development seem to disappear. We present recent results on contour-based prediction for intra coding, a KLT depending on scene and intra prediction direction for coding the prediction error and texture synthesis to replace conventional texture coding for uniform parts of images. Especially contour-based prediction and texture synthesis depend heavily on computer vision algorithms. While typically failures of efficient prediction can be compensated by coding the prediction error and hence a higher data rate, texture synthesis in video coding does not have this safety leash.Vortragende(r)Prof. Dr.-Ing. Jörn Ostermann KontaktKerstin Smounig (kerstin.smounig@aau.at)

VeranstaltungsortI.0.07Veranstalter Institut für MathematikBeschreibungIn previous work, several deterministic reduction procedures on plane trees (e.g. cutting away all leaves or cutting away all maximal paths ending in a leaf) have been studied. In this context, a parameter of particular interest is the number of removed nodes after iteratively applying the reduction a fixed number of times to a given plane tree.After briefly revisiting the previous results, we will discuss a new modeling approach based on a recursive description using additive tree parameters. Effectively, this new strategy leads to functional equations for the appropriate bivariate generating functions and thus allows us to analyze the behavior of a deterministic reduction acting on tree classes that are not part of the Catalan family. In the scope of this talk we will focus on the "cutting leaves"-reduction applied to the class of simply generated trees (i.e., a generalization of plane trees) and the class of Pólya trees (unordered, rooted trees).Vortragende(r)Benjamin HacklKontaktSenka Haznadar (senka.omerhodzic@aau.at)