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Web-based Geospatial Information Services and Analytical Tools for Natural Habitat Conservation and Management Liang Guo Thesis Committee Members Dr. Ming-Hsiang Tsou Dr. Douglas A. Stow Dr. Roger Whitney (Math & Comp. Science) Research purpose • Facilitate the sharing, access, and exchange of geospatial information • Enhance the utility of remotely sensed imagery, vector-based GIS and GPS data • Provide real-time analysis in tracking natural habitat conditions and status of preserves • Make the environmental decision making process more transparent and result more widely accessible Overall Problem • Traditional approaches for accessing large volumes of geo-spatial data are often time-consuming and problematic • Only a small number of experienced users can access GIS data and imagery by using sophisticated GIS/RS software Problem (cont’d) • The expensive GIS/RS software, specialized hardware, platform dependence, and inability to commute with remotely accessible information hindered further development of these systems • Due to the complexity and high cost of acquiring GIS and remote sensing data, most results and decision making are made behind the doors, using restricted information and with minimal public participation Project Need • There exists a strong incentive to develop a wider user access of geospatial data because of the high cost of acquiring data and the multi-discipline of environmental research. • There is a long-term need to call for easy-touse and cost-effective tools that can be shared by multiple users and perform the critical real-time analysis for environmental decision making. Technical Revolution • Internet technology allows for seamless integration with data storage, access, analysis, visualization and the creation of platform independence software. • The Internet is a perfect medium for disseminating geospatial information interfacing with multiple users Internet Technology Advance • From static to dynamic modeling • From restrict use to easy access • From stand-alone software packages to cross-platform applications • From Heterogeneous to compatible and standard network environment Project Objective • Provide a on-line data warehouse for efficient storage and access of geospatial information • Implement web-based mapping facilities for displaying remote sensing and GIS data • Develop algorithms that perform on-line analytical functions such as change detection over space and time • Test the prototype for the usability through web-based questionnaires Research Questions • How well can web-based applications enhance the utility of remotely sensed imagery and GIS datasets, and in turn contribute to the monitoring and understanding of complex environmental processes? • How well can online data warehouse and GIService be used to facilitate the sharing of geospatial datasets? • How well can web-based change detection tools and mapping functions be applied in a multidiscipline environmental management of natural resources? Programming Language and Software Selection • Programming Language – Java – JavaScript – HTML • GIS/RS Software – – – – ArcIMS 3.1 Erdas Imagine8.5 ArcGIS 8.2 ArcView3.2 • Web Software – Macromedia Dreamweaver – Microsoft FrontPage Prototype Web Service Functions Internet Map Server Prototype Evaluation Data Warehouse On-line Analytical Tools Data Warehousing • ArcCatalog – FGDC • • • • Citation Description Time Period Contact • Search Engine Internet Map Server Prototype Evaluation Data Warehouse On-line Analytical Tools Internet Map Server • ESRI ArcIMS • Intergraph GeoMedia • AutoDesk MapGuide • MapInfo 3-Tier Architecture Web Browser GIS/RS Database Internet Map Server Web Server Internet TCP/IP ArcIMS • HTML Viewer • Java Viewer Internet Map Server Prototype Evaluation Data Warehouse On-line Analytical Tools Why Java • “Write Once, Run Anywhere” • Open Source, easily and freely distributed • Object oriented, full-blown language • Extreme growth in functional APIs • Network centric, beyond computers • Advanced graphics and digital image processing 2-Tier Architecture Client Server 3 or n Tier Architecture (ArcIMS) • Client-Server Solution Adhere to all Internet/web standard • Utilizing existing GIS function, centralizes administration of data and GIS application software • Poor system interface • Lack of interactivity • Create many request 2-Tier Architecture (Java Applet) • Client solution • Modern GUI and flexible interaction • Good performance for operation • Less Internet traffic • No specific software and hardware requirement • Difficult for complex data processing • Lack of security Java APIs • Client is Applet –Abstract Window Tookit (AWT) –Swing –Java2D –Java Advanced Imaging (JAI) • Swing, Java2D, and JAI Brower needs Java 1.3 plug-in Image Transparency Using Java2DAlphaComposite Rule Pixel-by-pixel transparency the source image over the destination image AlphaComposite ac = AlphaComposite.getInstance(AlphaComposite.SRC_OVER); float alpha = 0.5f; ac = AlphaComposite.getInstance (AlphaComposite.SRC_OVER, alpha); BufferedImage buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); Graphics2D graphic2D = buffImg.createGraphics(); graphic2D.drawImage(bottomImage, 0, 0, null); graphic2D.setComposite(ac); graphic2D.drawImage(topImage, 0, 0, null); g.drawImage(buffImg, null, 0, 0); http://map.sdsu.edu/arc/imgoverlay/alpha.html Image Swipe • drawImage(image, x1,y1,w1,h1, x2,y2,w2,h2, observer) Width (W) Height (H) • drawImage(image, x,y,w,h,observer) (x,y) http://map.sdsu.edu/arc/imgswipe/index.htm SWOT Analysis Internet Map Server Prototype Evaluation Data Warehouse On-line Analytical Tools On-line Questionnaire Prototype Evaluation • SWOT – Strength – Weakness – Opportunity – Threat SWOT ANALYSIS What are you advantages? S What can you improve? W What do you do well? What do you do poorly? What is better than others? What should you avoid? What good opportunity are you facing? O What are the interesting trends are you aware of? What obstacles are you facing? T What are your competitors doing? On-line Questionnaire • Two Mission Trail Park Rangers • Four GIS, Remote Sensing Professionals • Four Graduate Students Prototype Website • Project Web Site http://map.sdsu.edu/arc Strength • Easy to access, cross-platform • Simplified and user-friendly interface • No software requirement, no hardware installation, no license • Cost reduction, maximum availability of information to the public • Facilitate the exchange and sharing high-cost of geo-spatial information between multi-discipline users Weakness • Lack of advanced analytical capability and integration with dynamic modeling • The desired performance is relied on higher bandwidth requirement • Different levels of user’s technique understanding can not be taken for granted Opportunity • Improved public awareness and participation with geospatial information by giving process more transparent and result more accessible via the Internet • With the continuing development of webbased applications, more GIS/RS data can be shared in an efficient and timely manner. • High bandwidth availability can make performance more satisfactory and acceptable Threat • Need significant levels of programming skills and geometric algorithm • A comprehensive Internet GIS, and remote sensing application is difficult to be fully developed, only certain functions will be migrated into Internet • Web-based tool is ideal for demo and sharing of data, not capable of taking the place of desktop software Metadata • The content of FGDC metadata need to be simplified and standardized for the efficient and practical use of environmental program. • A well-organized index, sorting and search mechanism is much-needed to facilitate the exchange and sharing geo-spatial information Internet Map Server • ArcIMS and other web-based mapping facilities are only focused on GIS analytical capabilities. • Lack of interoperability with remote sensing and GPS data, there is a significant limitation to add remotely sensed imagery under current software architecture Java-based On-line Analytical Tools • Java has great potential for providing advanced analytical capabilities for remotely sensed imagery • Many Java APIs, such as Java2D, JAI are designed for digital image processing • Image size and format are still a major barrier for Java programming technology Future Development (Image Geo-referencing) y x Web-based Image Viewer 3.0 http://map.sdsu.edu/mobilegis/area/index.html Tile Image • Tile Image breaks the data into “tiles” which can be loaded on demand. • Only a small portion of a dataset is visible at any one time • Using a 2-dimensional array to assist fast retrieval of tiles. Image Pyramid • Internet solution to assist in displaying large datasets tileImage (i, j, k) 16X • Reduce memory overload • Multi-scale dependent tile images 4X 2X 1X Zoom Factor 8X Web-based Image Viewer 4.0 Conclusion • Web-based service can facilitate the access, sharing and manipulating geo-spatial information • Current technologies like Java, ArcIMS demonstrate a great potential in the application of GIS and remote sensing • Technical barrier such as bandwidth requirement, programming capability, and software limitation is a major concern for the further development Potential Use • High Resolution Imagery • Geographic Information System • Spatial Analysis - Scientific data visualization • • • • • • Medical Imaging Digital Photography Document Image Processing Computer Aided Design (CAD) Multi-media digital library Presentation software Acknowledgements Dr. Ming-Hsiang Tsou Dr. Douglas A. Stow Dr. Roger Whitney (Math & Comp. Science) The End John Kaiser Lloyd (Pete) Coulter Lina Cao John Ryan