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Multimedia Search and Retrieval. Shih-Fu Chang, Qian Huang, Thomas Huang, Atul Puri, and Behzad Shahraray Published as a chapter in Advances in Multimedia: Systems, Standards, and Networks, A. Puri and T. Chen (eds.). New York: Marcel Dekker, 1999. Presented by: Reza Aghaee
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Multimedia Search and Retrieval Shih-Fu Chang, Qian Huang, Thomas Huang, Atul Puri, and Behzad Shahraray Published as a chapter in Advances in Multimedia: Systems, Standards, and Networks, A. Puri and T. Chen (eds.). New York: Marcel Dekker, 1999. Presented by: Reza Aghaee For Multimedia Course(CMPT820) Simon Fraser University March.2005
Agenda • Introduction • Video Segmentation, Indexing and Browsing • Object-based Spatio-Temporal Search • Semantic-Level Content Classification and Filtering • Multimedia Meta Search Engines • Conclusions 2/24
Introduction Applications: • WEB Large-scale Multimedia Search Engines • Media Asset Management Systems • Audio-Visual Broadcast Servers • Personal Media Servers for Consumers 3/24
Video Segmentation, Indexing and Browsing • Hierarchical Segmenting • smaller retrievable data units • Hierarchical Grouping • larger yet meaningful categories • Layers of abstraction • commercials, news stories, news introductions, news summaries of the day 4/24
Video Segmentation, Indexing and Browsing • Low-level segmentation of video streams • Streams are segmented into shots, clips and key frames. • They Do not correspond to the real semantic structure • Large amount of low-level structures, hence, browsing inefficiency 5/24
Video Segmentation, Indexing and Browsing Semantic Segmentation of news programs 6/24
Video Segmentation, Indexing and Browsing • Relationship among semantic structures 7/24
Video Segmentation, Indexing and Browsing • Representation & Browsing Tools • Time lined presentation 8/24
Video Segmentation, Indexing and Browsing • Representation & Browsing Tools • -Visual Pres. For stories about E1 Nino 9/24
Video Segmentation, Indexing and Browsing • Representation & Browsing Tools • -Visual Pres. For stories about E1 Nino 10/24
Object-based Spatio-Temporal Search & Filtering • Query by: • Example • Meaningful real world objects • Low-level image regions with uniform features • Feature • Color, Texture, Shape, Motion, Spatio-temporal structure of image regions • Sketches • Users directly draw visual sketches 11/24
Object-based Spatio-Temporal Search & Filtering • Object-oriented search by feature and sketches • (a) & (c) are sketches by the user • (b) & (d) are returned as results 12/24
Object-based Spatio-Temporal Search & Filtering • VideoQ search system • Video decomposed into shots • Shot separation achieved by scene change detection • Salient video regions and objects extracted • Temporal attributes of regions are indexed 13/24
Object-based Spatio-Temporal Search & Filtering • Query processing architecture 14/24
Object-based Spatio-Temporal Search & Filtering • Interface of AMOS semantic object search engine 15/24
Semantic-Level Content Classification and Filtering • Idea is mapping images or videos to meaningful classes • Content modeling using probabilistic graphic models • Multiject (multimedia object) • Has a label • Summarizes the time sequences in from a probabilities, P( label | sequences) 16/24
Semantic-Level Content Classification and Filtering • Multiject categories • Sites, Objects, Events • Multiject Lifetime • Duration of multimedia input used to determine its probability • Multinet (multiject network) • Represents probabilistic dependencies between multijects 17/24
Semantic-Level Content Classification and Filtering • A multinet describes probabilistic dependencies between multijects 18/24
Semantic-Level Content Classification and Filtering • Indexing Multimedia with semantic templates (STs) • Use a set of successful queries instead of a single one • There could be audio or video templates or both Semantic Visual Templates 19/24
Semantic-Level Content Classification and Filtering • Components in development of STs • Generation • Used to generate STs for each semantic concept • Metric • Used to measure the fitness (similarity) of each ST • Applications • Used to develop a library of semantic concepts to facilitate video query 20/24
Semantic-Level Content Classification and Filtering Semantic Template Development - Slalom 21/24
Meta Search Engines • Gateways Linking users transparently to multiple search engines 22/24
Meta Search Engines • Basic Components • Query dispatcher • Selects target search engines by performance scores • Query translator • Translate query to a suitable script for the target • Display interface • Merges the results of each engine using performance scores 23/24
Conclusions • Semantic segmentation instead of low-level segmentation • Methods of semantic segmentation • Object-based semantic searches • Probabilistic models and template-based searches • Meta search engines architecture 24/24