600 likes | 615 Views
Learn about methods for efficient image retrieval online using HTML metadata with a focus on multimedia information retrieval (MMIR) and practical search strategies. Discover the importance of image search and explore different agent implementation languages.
E N D
CADIP Research atUW-Milwaukee Ethan Munson and Yelena Tsymbalenko
Research Foci • Languages for implementing agents • MS Thesis by Preeti Seshadri • Multimedia information retrieval • Exploiting metadata to improve MM IR • Yelena Tsymbalenko’s MS research • Models of media • Usability of information visualization • future work
Using HTML Metadata to Retrieve Relevant Images from the Web Yelena Tsymbalenko University of Wisconsin-Milwaukee
Why is image search important? • The Web is primary source of obtaining information. • Images are one of the most valuable sources of information available on the Web. • Few WWW image search engines currently exist. • Using textual search engines to find images manually is laborious.
A Requirement for Web Image Search • We need an efficient method of discovering and indexing image content. • Two main sources of information about image content: • image processing • associated text • text content • markup
Related work • WebSeek(J. Smith & S. Chang, Columbia University) • performs a semi-automated classification of the images • uses image file name for categorization • searches by browsing or searching through the categories • uses image features such as color content to find images of similar color
Related work • WebSeer(M. Swain et al., The University of Chicago) • uses associated text and markup to supplement information derived from analyzing image content • uses multiple kinds of metadata • decides which images are photographs
Why look for new methods for image retrieval? • The number of WWW documents is growing rapidly and constantly changing. • Image processing is complex and computationally expensive. • We need fast and efficient methods for finding images. • Extensive image processing is not necessary.
Our research • Obtain information about image content from HTML Source Code: • Explicit: file and HREF names • Implicit: markup structure • Determine which features of Web documents are best clues to image content
Search Strategy Examples • Image file name • Title of HTML document • Alternate text (ALT tag) • Text of hyperlink • Text of the same paragraph • Header text
Analysis Plans • Will collect data about search results for a number of queries (several dozen) • Suggestions for queries are welcome ! • Will test which clues are most effective • Are some redundant ? • Does a combination of clues produce better recall ? • Are some clues more precise ? • Is search performance dependent on query type ? • Proper names (Chaplin, Garvey) • Phenomena (riot, explosion)
Using HTML Metadata to Retrieve Relevant Images from the Web Yelena Tsymbalenko Department of Computer Science University of Wisconsin - Milwaukee yelena@cs.uwm.edu
Agent Implementation Languages • Preeti Seshadri’s thesis has two parts • Survey of languages • Pure scripting languages • Tcl, Perl • Scripting/general-purpose languages • Java, Python, Telescript • Resource management service for Java • Interface design • Partial implementation
Language Requirements • Good language infrastructure • OO or other good modularity features • Automated memory management • Decent performance • Byte-compilation is probably enough • Portability • Security • Mobile agents must either be trusted or controlled • Control is always better
Language Survey • Systems programming languages (C, C++) • high-performance, but non-portable and insecure • Pure scripting languages (Tcl, Perl) • low-to-medium performance, portable • limited security and communication services • Scripting/general-purpose languages (Java, Python, Telescript) • medium-performance, portable • more security and communication support
Systems Programming Languages • Native-code compilation yields very high performance • Native-code is not portable • compilation is too complex to perform at client site • Language definitions are limited • no security or coordination infrastructure • little is guaranteed about higher-level services • even exception handling is limited
Pure Scripting Languages • Tcl is a bad choice • poorly suited for larger applications • low performance • poor language infrastructure • non-OO, no threads, no exceptions • Perl is a bit better • performance is better, but not great • limited security • language complexity is high
Telescript • “Environment” for constructing agent societies • Proprietary (General Magic, Inc.) • Language, engine, communication protocols • Claimed to be fast, easy-to-use, secure • Core concepts • “places” are execution contexts and can be nested • No agent-to-agent communication • agents move to places and do things • Capability-based security (“permits”)
Python • An OO scripting language • Unusual dynamic type system • Many high-level data types • Socket-level networking support • Typical byte-compiled characteristics • portability, dynamic linking • Limited security support • “Restricted execution,” similar to sandboxing • appears poorly integrated with mobility
Java • General-purpose language widely used for scripting-style applications • Excellent language design • Medium performance • Strong security features • customizable “sandboxes” • Heavily and effectively hyped • portability is overrated • performance will probably never match C++
Security Issues in Java • Java is very secure, but problems remain • e.g. security managers are inflexible • Agent portability is a problem • A newly arrived agent must be trusted • sandboxing addresses the obvious trust issues • Denial of service attacks are still possible • deliberate and accidental • Java lacks standard resource management services
Resource Management Interface • Supports both monitoring and control • CPU time • memory • threads • Granularity is per-thread and per-threadgroup • Designed to work on bytecode, not source • can monitor “outside” agents
RunTimeException UsageException ThreadRegister ThreadRegister ChiefMonitor ExceedUse Class Structure has uses interface uses exception uses is
Interface Details • Initialization • Resource usage queries • consumption • limits • Resource usage control • set usage bounds and policy • reset usage bounds • Resource exceptions • interrupt-style control
Implementation Plans • Prototype requires that agent be built with internal monitoring support • agent’s implementor must cooperate • We want to impose monitoring on arbitrary mobile agents • Solution: bytecode rewriting • All interesting operations have well-defined representation in Java bytecode • Will wrap relevant bytecodes in monitoring code • Similar to Purify/Quantify
A Theory of Media for Multimedia Authoring and Browsing Systems
The Original Problem • Develop a multimedia document system that allows easy addition of new media modules • Kernel/shell architecture • Shells support individual media • text, graphics, video • Kernel provides medium-independent services • document structure, scripting language, style sheet system
Proteus Style Sheet System • Portable style sheet system • PSL style language adapts to application (or media module) • medium supported by application is specified with MSPEC language • Architecture designed for multiple, simultaneous presentations • Used in Ensemble document environment and in MPMosaic WWW browser