This paper describes a technique for audio clips retrieval. The audio clips are modeled using a common universal codebook. The codebook is based on a bag-of-features (BOF). The features extracted from all clips are grouped into clusters using the k-means algorithm. The individual audio clips are modeled by the normalized distribution of the numbers of cluster bins. The latent semantic indexing (LSI) is applied to the feature-audio clip matrix to represent the data in latent semantic space. Then the primary audio clip description is converted to the vector in anchor reference space. Each component of the anchor vector is a probabilistic similarity between this clip and the clip corresponding to the considered component. Then LSI is applied to new feature-audio clip matrix, mapping the data to the latent semantic space based on anchor representation. For audio retrieval the nearest-neighbor (NN) algorithm is exploited. The described algorithm demonstrates high retrieval performance.

Paper 1451-Wed3CaP.2

In this paper we investigate on-line zero-crossing based audio stream segmentation and classification into speech and other segments. We consider such segments as applause, noise of the auditorium, and silence. We demonstrate that the features extracted from zero-crossing are stable and valid to be used for speech and other signal discrimination and classification and don't require large amount of data for the training. We describe the optimal segmentation of unlimited audio signals using results of the frames classification. We demonstrate that using optimal segmentation is better than using traditional sliding window technique.

This paper describes the MPEG-7 compliant indexing and retrieval system iFinder based on XML and open source database technology. The iFinder system automatically extracts metadata from A/V-content and allows access to the enriched content by means of a client/server-based retrieval engine. This multimedia retrieval system allows for search and retrieval of short video segments in huge multimedia archives. As a reference application, the iFinder system is used to index speeches from the German Parliament. The user can search for fragments of political speeches and receives matching video segments through a video streaming service.

The design and implementation of the AT&T Communicator mixed-initiative spoken dialog system is described.The Communicator project, sponsored by DARPA and launched in 1999, is a multi-year multi-site project on advanced spoken dialog systems research.The main focus of this paper is on issues related to the design of mixed-initiative systems.In addition to describing our architecture and implementation of the complex travel task, the paper reports on some preliminary evaluation results.