Efficient Video Indexing on the Web: A System that Leverages User Interactions with a Video Player

In this paper, we propose a user-based video indexing method, that automatically generates thumbnails of the most important scenes of an online video stream, by analyzing users' interactions with a web video player. As a test bench to verify our idea we have extended the YouTube video player into the VideoSkip system. In addition, VideoSkip uses a web-database (Google Application Engine) to keep a record of some important parameters, such as the timing of basic user actions (play, pause, skip). Moreover, we implemented an algorithm that selects representative thumbnails. Finally, we populated the system with data from an experiment with nine users. We found that the VideoSkip system indexes video content by leveraging implicit users interactions, such as pause and thirty seconds skip. Our early findings point toward improvements of the web video player and its thumbnail generation technique. The VideSkip system could compliment content-based algorithms, in order to achieve efficient video-indexing in difficult videos, such as lectures or sports.Comment: 9 pages, 3 figures, UCMedia 2010: 2nd International ICST Conference on User Centric Medi

A Photographic Composition Assistant for Intelligent Virtual 3D Camera Systems

Abstract. A human photographer can frame an image and enhance its composi-tion by visualizing how elements in the frame could be better sized or posi-tioned. The photographer resizes elements in the frame by changing the zoom lens or by varying his or her distance to the subject. The photographer moves elements by panning. An intelligent virtual photographer can apply a similar process. Given an initial 3D camera view, a user or application specifies high-level composition goals such as Rule of Thirds or balance. Each objective de-fines either a One-D interval for image scaling or a Two-D interval for transla-tion. Two-D projections of objects are translated and scaled in the frame ac-cording to computed optima. These Two-D scales and translates are mapped to matching changes in the 3D field of view (zoom), dolly-in or out varying sub-ject distance, and rotating the aim direction to improve the composition.

非線形ばねで支持された弾性ブロックの連成振動の有限要素解析 : 弱非線形性を有する場合の検討

This paper describes vibration analysis using finite element method for an elastic block supported by a nonlinear concentrated spring. The restoring force of the spring has cubic nonlinearity. Finite element for the nonlinear spring is expressed and is connected to the elastic block modeled by linear solid finite elements. Further, the discretized equations in physical coordinate are transformed into the nonlinear ordinary coupled equations using normal coordinate corresponding to linear natural modes. This transformation yields computation efficiency. Influences of Young's modulus on nonlinear frequency responses for the elastic block are clarified