Modelling of content-aware indicators for effective determination of shot boundaries in compressed MPEG videos

In this paper, a content-aware approach is proposed to design multiple test conditions for shot cut detection, which are organized into a multiple phase decision tree for abrupt cut detection and a finite state machine for dissolve detection. In comparison with existing approaches, our algorithm is characterized with two categories of content difference indicators and testing. While the first category indicates the content changes that are directly used for shot cut detection, the second category indicates the contexts under which the content change occurs. As a result, indications of frame differences are tested with context awareness to make the detection of shot cuts adaptive to both content and context changes. Evaluations announced by TRECVID 2007 indicate that our proposed algorithm achieved comparable performance to those using machine learning approaches, yet using a simpler feature set and straightforward design strategies. This has validated the effectiveness of modelling of content-aware indicators for decision making, which also provides a good alternative to conventional approaches in this topic

Experimental study on a two-dimensional fluid-structure interaction reference test case

Experimental studies on reference test cases are of capital importance to support the development of models and coupling strategies for simulations on fluid-structure interaction problems. The need for experimental test cases specially addressed for the validation and diagnostic of numerical tools has triggered the present contribution to design and to study two-dimensional reference test cases both in laminar and turbulent flows. From the experimental view point, investigations on coupled unsteady flow and structure motions require specially adapted test rigs and measuring techniques to obtain accurate timephase resolved results. Therefore a new experimental facility to be operated with a large range of viscous liquids was built exclusively for the present study. It made possible to perform measurements, using optical laser measurement techniques, in laminar and turbulent flows under very well controlled boundary and working conditions. A Particle Image Velocimetry (PIV) measuring system was adapted to measure both the periodical flow velocity field and the structure deflection modes. The first reference test cases were conducted in laminar flows (Reynolds number ? 200). In that period an extended investigation was performed on the coupled motion of relatively simple two-dimensional reference structures immersed in a high viscous fluid (kinematic viscosity of 0,000164 m2/s). This paper presents a complete characterization of a reference test case for an incoming velocity of 1,45 m/s