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International Society for Photogrammetry and Remote Sensing

International Society for Photogrammetry and Remote Sensing ISPRS Commission VI Workshop, Dar es Salaam, Tanzania, 25-28 March 2002 MAPPING & IMAGING AFRICA ON THE INTERNET Mike Shand Department of Geography & Topographic Science University of Glasgow

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International Society for Photogrammetry and Remote Sensing

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  1. International Society for Photogrammetry and Remote Sensing ISPRS Commission VI Workshop, Dar es Salaam, Tanzania, 25-28 March 2002 MAPPING & IMAGING AFRICA ON THE INTERNET Mike Shand Department of Geography & Topographic Science University of Glasgow mshand@geog.gla.ac.uk http://www.geog.gla.ac.uk/~mshand/

  2. OVERVIEW The Internet is awash with a wealth of maps and spatial imagery, some crude and basic, some refined and highly developed. With increasing internet access and faster bandwidths, Africa is well-placed to benefit from Internet Mapping technology. There are three possible options for delivering and viewing maps and imagery over the Internet static, animated and interactive. This paper will review and illustrate current Internet Mapping technology utilising example maps and images of Africa and in particular Tanzania.

  3. Internet Connectivity in Africa The Internet is unevenly distributed between and within countries in Africa. South Africa (55%)together with the North African countries of Egypt, Morocco, Tunisia and Algeria account for 75% of total subscribers in Africa.

  4. Internet Developments in Africa PROBLEMS Average of 1 phone line per 50 persons in Africa (in East and West central Africa 1:350) Elderly analogue communications subject to power irregularities. Slow connectivity speeds and high costs are common resulting in overseas hosting of many Africa web sites and e-mail servers in USA and Europe. SOLUTIONS Satellite, digital, cellular and fibre optic telecommunications technology now being recognised and adopted at government level in Africa. New fibre optic ring around Africa due in 2002 with world wide links. East African Co-operation (EAC) project established to install fibre optic backbone between Dar es Salaam, Nairobi and Kampala.

  5. African Maps & Imagery on the Internet MAP USES ON WEB SITES Geographical location, route-finding, illustration and map servers MAP USERS ON WEB SITES Private companies and businesses (e.g. travel, transport, commerce) Education establishments and researchers News and weather services Government and non-government organisations

  6. African Maps & Imagery on the Internet MAP USES ON WEB SITES Extract from the newafrica.com web site offering an extensive set of maps to view, print or download.

  7. African Maps & Imagery on the Internet MAP USES ON WEB SITES Example of basic maps used to enhance a web site.

  8. African Maps & Imagery on the Internet DEDICATED MAP SERVER WEB SITES Example of small-scale mapping supplied free over the Internet.

  9. African Maps & Imagery on the Internet DEDICATED MAP SERVER WEB SITES Online ordering from Surveys & Mapping, South Africa

  10. African Maps & Imagery on the Internet DEDICATED MAP SERVER WEB SITES A dedicated map site hosted by the USGS offering online maps and data

  11. Internet Mapping Technology FILE FORMATS USED ON THE INTERNET Raster andVector JPEG; GIF; PNG; TIFF -PDF; FLA; SVG; VRML Raster Zooming Vector Zooming

  12. How to Create and View Maps & Imagery on the Internet MAPPING AND IMAGING OPTIONS Static mapping sites allow the user to access fixed raster map data or remotely sensed images to view or download. Animated mapping sites allow the user to view raster or vector maps or imagery dynamically as the content changes. Interactive mapping sites allow the user to zoom or pan high resolution raster or vector maps and images and to make decisions on content or design.

  13. How to Create and View Maps & Imagery on the Internet MAPPING AND IMAGING OPTIONS Static mapping sites allow the user to access fixed raster map data or remotely sensed images to view or download.

  14. How to Create and View Maps & Imagery on the Internet STATIC MAPS & IMAGERY Static Maps and Imagery can be created by RASTER SCANNING or FILE CONVERSION Two raster file formats are currently used for direct viewing of maps and imagery on Internet Browsers GIF(.gif) andJPEG (.jpg; .jpeg) Static raster GIF or JPEG files cannot be zoomed or edited from within browsers such as Netscape or Internet Explorer.

  15. How to Create and View Maps & Imagery on the Internet STATIC MAPS & IMAGERY RASTER SCANNING Advantages ease of use and availability image manipulation possible before uploading Disadvantages file size / resolution conflict high resolution=large file =slow download times Unfortunately there are more bad examples of raster scanned maps than good ones on world wide web sites

  16. How to Create and View Maps & Imagery on the Internet STATIC MAPS & IMAGERY FILE CONVERSION Vector to raster file conversion can be accomplished directly from within vector GIS, mapping or graphics software (e.g. ArcView; MapInfo; Adobe Illustrator; Macromedia Freehand; CorelDraw), or indirectly with intermediate software (e.g. Adobe Photoshop; Paintshop Pro;Corel Photo-Paint); or via file conversion utilities(e.g. GraphicConvertor; GIFConvertor). Most GIS, mapping and graphics software now offer a web option for file export and conversion to web compatible formats.

  17. How to Create and View Maps & Imagery on the Internet ANIMATED MAPS & IMAGERY Animated mapping sites allow the user to view raster or vector maps or imagery dynamically as the content changes.

  18. How to Create and View Maps & Imagery on the Internet ANIMATED MAPS & IMAGERY Animated Maps and Imagery can be created from vector maps or raster imagery using multiple image file formats (Flash, GIF89a , MPEG) or by delayed refresh of screen maps . Animated maps can be created from vector maps produced in graphics software packages (eg Illustrator, Freehand, CorelDraw) by saving each map layer as a separate raster file(GIF or JPEG). Animated imagery can be created simply by overlaying a series of matching air photos or satellite images.

  19. How to Create and View Maps & Imagery on the Internet ANIMATED MAPS & IMAGERY Gif89a format allows multiple images to be included in one file

  20. How to Create and View Maps & Imagery on the Internet INTERACTIVE MAPS & IMAGERY Interactive mapping sites allow the user to zoom or pan high resolution raster or vector maps and images and to make decisions on content or design.

  21. How to Create and View Maps & Imagery on the Internet INTERACTIVE MAPS & IMAGERY can be created with vector or raster mapping, GIS and imaging software. Mapping plug-ins include Macromedia Flash, Shockwave and Adobe Acrobat. GIS plug-ins include Autodesk Mapguide, Intergraph Geomedia Web Map, ESRI Internet Map Server, and Dataview Solutions Pavan web.Publisher. Imagery is best viewed in specialist file compression plug-ins such as Lizardtech Mr SID or ERMapper ECW. Access to file databases can also be by user entry to SUBMITTED FORMS or directly via browser or client/server PLUG-INS, Applets, and Javascripts.

  22. How to Create and View Maps & Imagery on the Internet INTERACTIVE MAPS & IMAGERY Interactive maps or imagery (raster or vector) can be viewed by user query of a database via keyboard to a submitted form. This allows the user to make decisions on content or design.

  23. How to Create and View Maps & Imagery on the Internet INTERACTIVE MAPS & IMAGERY Interactivevector maps can be viewed, zoomed and queried by the use of browser plug-ins at high resolutions and large zoom factors without loss of quality Mapping PLUG-INS include Adobe Acrobat and Macromedia Flash/ Shockwave. GIS browser PLUG-INS include Autodesk MapGuide; ESRI Geomedia Web Server. Imagery and scanned map browser PLUG-INS include Lizardtech MrSID and ERMapper ECW.

  24. How to Create and View Maps & Imagery on the Internet Example of the vectorPLUG-IN from Adobe Acrobat.

  25. How to Create and View Maps & Imagery on the Internet Example of the vectorPLUG-IN from Macromedia Shockwave.

  26. How to Create and View Maps & Imagery on the Internet Example of the vector GIS viewing PLUG-IN from ESRI MapObjects.

  27. How to Create and View Maps & Imagery on the Internet Example of the vector GISPLUG-IN from Autodesk MapGuide.

  28. How to Create and View Maps & Imagery on the Internet Example of the Mr SID viewer interface from Lizardtech.

  29. How to Create and View Maps & Imagery on the Internet Example of the ECW viewer interface from ERMapper.

  30. MAPPING & IMAGING AFRICA ON THE INTERNET Conclusion The Internet has created a new medium for maps and spatial data, the Mapping Industry must rise to the new technology of Web Cartography. Research and guidelines should be developed to ensure quality web map design. Internet map technology is moving fast and will not stand still.Users will demand faster web distribution and more online interaction. New developments include devices with Internet access such as PDA’s, WAP phones, GPS and XML / GML enabled laptops and in-car computing. The real challenge for Africa if it wishes to participate in the Internet mapping revolution is to make available up-to-date topographic maps at national level in fully structured digital and GIS compatible formats.

  31. MAPPING & IMAGING AFRICA ON THE INTERNET Further Information Further web mapping information including free ONLINE WEB MAPPING WORKSHOPS can be found at: Mike Shand – Mapping the Web Workshop http://www.geog.gla.ac.uk/~mshand/Thompson2000/www2000/webtitle.htm ITC Web Cartography: developments and prospects http://kartoweb.itc.nl/webcartography/webbook/index1.htm Mike Peterson, ICA Commission on Maps and the Internet http://maps.unomaha.edu/ICA/Maps%26Internet/Research/Questions.html

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