Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Volunteered Geographic Information and OpenStreetMap


Published on

Short introduction to the subject of Volunteered Geographic Information and outlining some of the characteristics, issues themes of VGI
and then a comprehensive talk about the OpenStreetMap Project.
By Tim Waters, at AGI Northern Group (SIG), April 2009, Manchester University

Published in: Technology, Business
  • provides good examples of OpenStreetMaps and its development
    Are you sure you want to  Yes  No
    Your message goes here

Volunteered Geographic Information and OpenStreetMap

  1. 1. “OpenStreetMap is a free editable map of the world made by people like you!” AGI NORTH 23 April 2009
  2. 2. About Tim Tim Waters Freelance GIS Consultant and Web Developer Long time OpenStreetMap contributor & evangelist Leeds UK blog: latest:
  3. 3. VGI
  4. 4. VGI Volunteered Geographic Information (VGI) is the harnessing of tools to create, assemble, and disseminate geographic data provided voluntarily by individuals (Goodchild, 2007). Some examples of this phenomenon are Wikimapia, OpenStreetMap, and Google MyMaps. These sites provide general base map information and allow users to create their own content by marking locations where various events occurred or certain features exist, but aren’t already shown on the base map. VGI is a special case of the larger Web phenomenon known as user-generated content. Straight outa Wikipedia.............there's more pictures later.
  5. 5. Power of Volunteered Geographic Information 1. Potential of VGI to expand/complete/improve existing databases, infrastructures, & archives; 2. Potential of VGI to enable us to gather/produce new forms of spatial information that use local knowledge to inform previously un- answerable questions, unknowable phenomenon, and new social and political practices. (“new knowledge practices”)
  6. 6. Concerns: what drives people to do this, how accurate are the results, will they threaten individual privacy, and how can they augment more conventional sources Basics: Web2 – web search, Google, communities technologies, GPS cameras, network, computers Crowd sourcing price, closed of NMAs (OS licences) Push factor Openness Easy Amateur --- Future with NMAs etc. Decline in world mapping. Remote sensing and VGI filling in the gap. Mapping economically determined. None in developing world. Expensive to keep up to date. AND Map2.0
  8. 8. Google Earth!
  9. 9. A geocoder that uses k-means clustering of geotagged images
  10. 10. Flickr Shapefiles
  11. 11. ARGH!!!! Just show me some nice maps
  12. 12. Maps!
  13. 13. You can get the data.
  14. 14. Berlin
  15. 15. Copenhagen
  16. 16. Amsterdam
  17. 17. Madrid
  18. 18. NYC
  19. 19. Baghdad
  20. 20. Sydney
  21. 21. Pretoria
  22. 22. Kinshasa
  23. 23. Map what you like
  24. 24. Germany 2006
  25. 25. Germany 2007
  26. 26. Germany 2008
  27. 27. OSM in a nutshell Most other maps are non-free Vector data for custom maps is difficult to obtain licences Users can improve the map Fast updates Commercial maps have intentional errors Many areas of the world are mapped poorly Speciality maps Innovative uses
  28. 28. Mapping data is not free
  29. 29. Not free as in freedom Maps Copyright The maps are based upon Ordnance Survey material with the permission of Ordnance Survey on behalf of the Controller of Her Majesty's Stationery Office © Crown copyright. Unauthorised reproduction infringes Crown copyright and may lead to prosecution or civil proceedings. Luton Borough Council. 100023935, 2006 The Ordnance Survey map data included within this web site is provided by Luton Borough Council under licence from the Ordnance Survey in order to fulfil its public function to act as a local authority. Persons viewing this mapping should contact Ordnance Survey copyright for advice where they wish to licence Ordnance Survey map data for their own use
  30. 30. Full of mistakes, car centred
  31. 31. Mistakes cannot be corrected
  32. 32. Cannot re use or reprint
  33. 33. Coverage economically determined
  34. 34. Change happens inflexible
  35. 35. Katrina
  36. 36. 100,000 users 330 million nodes 800million trackpoints 1 Billion Tags
  37. 37. Donate data & free data
  38. 38. Tiger / Line
  39. 39. Other Sources: Donations Gaza, people donated to buy imagery for OSM
  40. 40. Yahoo allow use of imagery
  41. 41. Landsat
  42. 42.
  43. 43. Or, just D.I.Y! Mapping party
  44. 44. Mapping Parties Galore!
  45. 45. Mapping Party Field Trip 7 June Sunday Patley Bridge
  46. 46. How to do it? Editors, online. Do it from home! Mikels Case Study - Brighton
  47. 47. Case Study: Mikel in Brighton
  48. 48. Mapping Party, September 2006
  49. 49. OSM Brighton, December 2006
  50. 50. Summer 2007
  51. 51. Winter 2007 Today
  52. 52. Today
  53. 53. 1.0
  54. 54. His Process
  55. 55. Download existing data to GPS
  56. 56. Print Out Map for Notes, Bicycle
  57. 57. Network Diagram
  58. 58. Upload GPS Tracks to Computer
  59. 59. Upload Tracks
  60. 60. Draw Over Them
  61. 61. Editing in Potlatch, rollbacks, history
  62. 62. Tech
  63. 63. The OSM-”Tool Chain” Editors Database Renderer Viewer Potlatch tiles@ “Google” API (Flash) home tiles (Rails) Slippy osmarender, Map JOSM pdfatlas, (Open (Java) MySQL ... Layers) “Google” ... Mapnik planet tiles dump
  64. 64. RESTful API <way id='7972254' timestamp='2007-09-24T12:36:29+01:00' user='chippy' visible='true'> <nd ref='59608510' /> <nd ref='59608509' /> <nd ref='59608516' /> <nd ref='59608515' /> <nd ref='59608514' /> <nd ref='59608513' /> <nd ref='59608512' /> <nd ref='59608511' /> <nd ref='59608510' /> <tag k='created_by' v='JOSM' /> <tag k='building' v='retail' /> <tag k='name' v='White Rose Shopping Centre' /> <tag k='amenity' v='shopping_centre' /> <tag k='note' v='huge building' /> </way>
  65. 65. Trackpoints Nodes
  66. 66. Tags! amenity = hospital name = Saint James POIs emergency = yes Ways highway = primary name = Otley Road ref = A660 Areas highway = residential name = Chestnut Lane oneway = true surface = flags leisure=nature_reserve
  67. 67. simple data format tagging for metadata standard map tiles
  68. 68. Volunteers. OSM donation drive Over $22,500 raised in 3 days for new server in early February Goal was $15,000 servers api 0.6 downtime
  69. 69. API 0.6 Changesets user id version numbers Diffs can be applied
  70. 70. Licence Now: Creative Commons by Share Alike Future: Open Database Licence CC = everything is shared alike OdbL = only the database should be shared Both allows commerical use
  71. 71. healthy ecosystem tools renderers editors routers applications
  72. 72. Potlatch
  73. 73. JOSM
  74. 74. Merkaartor
  75. 75. Mapnik
  76. 76. ORS
  77. 77. Many mobile apps
  78. 78. Freemap Slovakia & contours
  79. 79. Cycle Map
  80. 80. OpenPisteMap
  81. 81. Open Street Bugs
  82. 82. healthy ecosystem tools renderers editors routers applications
  83. 83. Ecology System Iteration Gets better & stronger
  84. 84. Folksonomy But with standardised conventions. Voting mapping reality proposed adoption iteration
  85. 85. landuse=vineyard vs landuse=farm crop=grapes
  86. 86. Edit Wars
  87. 87. Taking a leaf. Tapping the crowd.
  88. 88. Map Maker from Google.
  89. 89. AND Map2.0
  90. 90. Peoples Map (dot dot dot)
  91. 91. Quality Is it any good? OSM is sometimes the ONLY source for mapping data Map Action Developing World
  92. 92. How good it the data?  − Positional accuracy − Completeness − Attribute accuracy and completeness − Consistency − Semantic accuracy − Temporal quality (up-to-date-ness)
  93. 93. Map Compare
  94. 94. Dair Grant Errors in Google / Teleatlas
  95. 95. Errors in OSM but, they can be fixed :)
  96. 96. OSM 193 bugs per 10km2 Google 89 bugs per 10km2
  97. 97. OpenStreetMap vs. Google/TeleAtlas Street Coverage The size of the circles are proportional to the values for both, so small circles equal poor coverage and large circles equal good coverage. The overlap of the circles shows who appears to be doing better (orangey/brown showing means that osm is doing better, blue google). OSM is the top layer so a tie will have OSM looking better, but you can click the layers on and off to see both views of the coverage.
  98. 98. The data is very interesting. Quickly comparing the roads layers against OSM in Kenya show good correspondence where there is Yahoo aerial imagery to trace against — if OSM had access to the same imagery, I imagine we’d be pretty much equivalent country-wide. MapMaker is slightly more complete in central Nairobi; I put that down to Google having full time employees in Nairobi who work on MapMaker Green = OSM Purple = Mapmaker
  99. 99. OSM VS OS Coverage Blue = OSM better UCL Muki Haklay
  100. 100. Meridian 2 and OSM – Motorway  comparison UCL Muki Haklay
  101. 101. Positional accuracy Area Average On each tile, 100  difference points sample with (m) evaluation of distance Barnet 6.77 between OSM and Highgate 8.33 Meridian 2 New Cross 6.04 South Norwood 3.17 Can see significant  differences: from Sutton 4.83 about 3m to over 8m Total 5.83 UCL Muki Haklay
  102. 102. The analysis shows that, where OSM was collected by several users and benefited from some quality assurance, the quality of the data is comparable and can be fit for many applications. The positional accuracy is about 6 metres, which is expected for the data collection methods that are used in OSM. The comparison of motorways shows about 80% overlap between OSM and OS . The challenges are the many areas that are not covered – currently, OSM has good coverage for only 25% of the land area of England 12 Months ago... UCL Muki Haklay
  103. 103. Field Trip! 7 June Sunday Patley Bridge Tim Waters Thanks! Pub?