Multimodal indexing of digital audio-visual documents: A case study for cultural heritage data

This paper describes a multimedia multimodal information access sub-system (MIAS) for digital audio-visual documents, typically presented in streaming media format. The system is designed to provide both professional and general users with entry points into video documents that are relevant to their information needs. In this work, we focus on the information needs of multimedia specialists at a Dutch cultural heritage institution with a large multimedia archive. A quantitative and qualitative assessment is made of the efficiency of search operations using our multimodal system and it is demonstrated that MIAS significantly facilitates information retrieval operations when searching within a video document

Motion-based MPEG video summarization

A new, fully automated summarization algorithm of MPEG compressed videos is designed to address the challenge of content based video retrieval. This algorithm segments the MPEG stream motion vector magnitudes using a seed growing region technique. Following the spatial segmentation of each frame, an intra-frame class-merging operation is performed. The resulting spatio-temporal classification is filtered to extract the video sequence main objects. The gravity centers of the identified objects are computed in background and fixed references, and are used to estimate the parameters of a 2-order ARMA model which summarizes the motion. Experimental results verify the effectiveness of the proposed algorithm and emphasize the usefulness of the MPEG motion vectors for object motion estimation

Efficient Shot Change Detection on Compressed Video Data

[[abstract]]Video segmentation is an elementary work for video index construction. A video sequence is usually decomposed into several basic meaningful segments. In this paper, we propose a new approach to detect shot changes for video segmentation, which is based on the processing of MPEG compressed video data. This approach takes advantage of the information implied in the compressed data. The reference ratios among video frames are analyzed to determine their similarities. A shot change is detected if the similarity degrees of a frame and its adjacent frames are low. A function is used to quantize the results into the shot change probabilities. Considering the motion variations of video contents between frames, a conversion function is designed to increase the correctness of the shot change detection. T h e experimental results showed the performance of our approach.[[fileno]]2030208030078[[department]]資訊工程學