An technical and philosophical overview of Open Street Map from the perspective of Cambodia, which has rather poor coverage, but strong need for open geodata.

1. Open Street Map | Cambodia
Go Beyond Google Maps (and Party)
June 27 At InSTEDD Cambodia By Chris Blow Http://unthinkingly.com

2. Meta: Why we are here
✤ What the heck is this OSM?
✤ Why on earth would I use OSM?
✤ Who is really using OSM?
✤ How do I use the map already?!

3. What is OSM?
✤ A database containing map data in vector format. Data is annotated
using free-form tagging that is managed by community consensus.
✤ A variety of software tools for editing map data.
✤ A range of methods for rendering and viewing the data in map form,
including on-line slippy maps, SVG, PDF and various hand-held
formats.
✤ A map-data API and static data dump of the whole planet.

4. What is Open Street Map
OpenStreetMap does for maps what Wikipedia does for Encyclopedias
http://wiki.openstreetmap.org
http://openstreetmap.org

5. Who uses it?
✤ The big guys!
✤ Meedan (my nonprofit)
✤ Governments
✤ Geocommons
✤ Cloudmade
✤ Normal people
✤ Normal-ish people :)

6. Flickr!

7. The Toolchain

8. How do I make maps?
You can make maps with:
✤ GPS tracklogs
✤ Aerial imagery
✤ Historic out-of-copyright maps
✤ Public domain data-sets
✤ An astrolabe ->
http://www.flickr.com/photos/charlestilford/189670488/

9. What is OSM?
Uh – don’t we
already have that?

10. It’s about intellectual property
Creative Commons Attribution-ShareAlike 2.0 license

11. Why OSM: Free as in Freedom
Most maps that you might think of as
free actually have legal or technical
restrictions on their use, holding back
those that wish to use them in creative,
productive or unexpected ways.
RMS by http://www.flickr.com/photos/dunechaser/160405823/

12. http://www.flickr.com/photos/18789396@N00/144251305/
Google License vs. OSM
Google: “We own your work”
- Non-commercial use only
- non-compete with Google services
- strict attribution
- everpresent Google logo
http://www.google.com/mapmaker/
mapfiles/s/terms_mapmaker.html
http://code.google.com/apis/maps/
terms.html

13. http://www.flickr.com/photos/18789396@N00/144251305/
Google License vs. OSM
OSM: “Hai friends, let’s share.” All OpenStreetMap software is GPL, and content is
published under the Creative Commons (CC-BY-
SA).

14. Why use OSM?
Social reasons to map ...
✤ In Detroit the city is geocoding walking trails.
✤ With Hurricane season there are lots of people geocoding where
shelters are.
✤ Mapping conveniences for pedestrians in particular places
✤ Mapping your own neighborhood
✤ Fun!

15. Why use O$M?
Business Reasons
✤ An NYC company social lite is doing place
marking with bars using mobile web.
✤ iPhone and Android have a lot of applications
which are innovating on the geo aware
capabilities of the phone.
✤ OSM’s openness doesn’t keep you from making
money on services and innovation!
http://gpsobsessed.com/200-garmin-edge-305-more-acccurate-than-199-trails-iphone-app/

16. Limitations
✤ Not as much data as Google or
Yahoo!
✤ Not backed by commercial
interests: not as robust an API
✤ Tools are geek-oriented not
consumer level ... yet
http://www.flickr.com/photos/41677782@N00/3453490890/
http://www.flickr.com/photos/71594384@N00/2695499877/

17. http://www.flickr.com/photos/64419960@N00/2372327933/
Advantages
✤ Expand the map yourself
✤ Innovate freely
✤ Ownership and licensing
✤ Customization of
presentation
✤ Customize placenames and
translations
✤ Get the entire damn planet!
(160 GB drive required)

18. Katrina example: OSM is faster
bridge out ....
... still on the map
(then it was repaired)
... but then not on the map

19. GOOG vs. OSM
OSM Google: win

20. GOOG vs. OSM
OSM Google: win

21. GOOG vs. OSM
OSM Google: win

22. GOOG vs. OSM
OSM Google: win by a hair

23. GOOG vs. OSM
OSM Google: win by a hair

24. GOOG vs. OSM
OSM Google: win

25. GOOG vs. OSM
OSM: win Google

26. How to create an Open Map
✤ GPS - This is the most common way of gathering
data for OSM, and for fully mapped areas is
essential. If you don't have a GPS they are
sometimes available for loan or you can create maps
from other users' data.
✤ Your own photography or maps - Make sure these
are completely free to copy and use with OSM. Most
data is not as free as you would think.
✤ Data may already be collected, that requires people
to convert into a map. An example of this is the
collaborative mapping project for Korea.

27. Strangely ....
They’re giving it away!
✤ Yahoo! Imagery, Landsat and
NPE maps are available to
OSM for extracting data from.
Accuracy is important though,
so only map places you've
been. These sources add
greatly to OSM, but data can't
be built on these alone.

28. Sort of ...
Sort of ... (low-res
photos, not
real data)

29. Sort of .... Tracing with Potlatch

30. Tracing

31. Tracing it in
✤ Yahoo! have provided OSM with aerial photography of a range of the
larger urban areas around the world.
✤ Tracing the photography is allowed for the purpose of generating
maps, but Yahoo’s data (e.g. street names) must NOT be imported
into OSM.
✤ Landsat is low zoom satellite imagery from the NASA. They are
copyright free.

32. Not just “Streets!”
✤ Points of interest
✤ Surface type
✤ Width
✤ Number of lanes

33. Palestine
✤ The OpenStreetMap Wiki has an
extensive collection of Palestinian
geodata on the internet
✤ One of the most inspiring and
useful examples of
crowdsourcing.

34. Palestine
http://wiki.openstreetmap.org/wiki/WikiProject_Palestine_Gaza

39. Wait, what about Cambodia?
✤ How much data is there?
✤ How much can we add?
✤ Who will maintain it?
✤ Why is it useful?

40. OSM Phnom Penh
June 25, 2009

41. OSM Phnom Penh
June 25, 2009

42. OSM Phnom Penh
June 25, 2009

43. OSM Phnom Penh
June 25, 2009

44. OSM Phnom Penh
June 25, 2009

45. Google has way more data so far
Google Mapmaker Phnom Penh June 25, 2009

46. Uh, can we really do this?
(map Phnom Penh and Cambodia that is)

47. Actually ... watch all 2008 edits to OSM!
http://www.vimeo.com/2598878

48. Yes!
User adoption
is increasing
rapidly

49. UK
“complete”
in 1-2 years

50. Uh, How?

51. APPING PARTY///MAPPING PARTY///MAPPING PARTY///MAPPING
OSM Mapping Party!
///MAPPING PARTY ///MAPPING PARTY//
✤ “Parties”
make it
fun to enter
map data
✤ Outside we go!
http://www.flickr.com/photos/96679304@N00/57629984/

52. Let’s map!
1.Head outside
2.Take a pen and paper
3.Take a GPS device
4.Get a signal
5.Walk the neigborhood
6.Mark waypoints
///MAPPING PARTY///MAPPING P
7.Rock
///MAPPING PARTY

53. Using GPS
✤
A GPS device is deigned to pinpoint a location anywhere on the earth. It uses an
aerial to receive transmissions from orbiting satellites.
✤
The received signal is triangulate and records the position as latitude and longitude
coordinates.
✤
Turn the receiver on in an area not obstructed by tall buildings or under a tree.
✤
A waiting period for an initial fix is usually achieved within several minutes.
✤
Orbiting satellites will triangulate your location, which will appear as a readout on
the screen. You are represented as the center of the screen. It will also include a
measurement of accuracy. Accuracy less than twenty (20) feet is considered normal.
✤
With GPS in hand, move about and the satellites will track your progress, turn by
turn and by direction facing.

54. GPS device to GPX
LoadMyTracks GPS Babel
✤ Use software like easygps
✤ Import from your device the more useful GPX format (XML)
✤ Now you are ready to import!

55. Upload to OSM
✤ Upload your track directly to OSM
✤ Make it public
✤ Then it is available for use for tracing
✤ Careful: it wont be always accurate!

56. Create a map from GPS track
✤ Can be edited in Potlatch window
✤ Or download and JSOM (the power tool)
✤ Experiment first in “play” mode! (not live editing)

57. Potlatch and JOSM
✤ Potlatch is an editor:
✤ Flash
✤ Easy to get started with
✤ Not super powerful
✤ JOSM is an editor:
✤ Java
✤ a power tool for serious editing

58. Potlatch (default editor)
- Flash
- Easy-ish
- for quick edits
- under the
“edit” tab in
OSM

59. JOSM
power
users

60. Add tags, use conventions
✤ Make sure you use
standard tags
✤ Don’t be too afraid of Key : Value
mistakes, just get
started and learn
✤ Get in touch with the
community

61. Now you can smell the freedom
You can do a pseudo-sensical, subjective tags!
super_awesome_restaurant:true
(but ... that doesn’t mean you should)
MAPPING PARTY///MAPPING PARTY///MAPPING PARTY///MAPPIN

62. Use the community standards!
http://wiki.openstreetmap.org/wiki/Map_Features

63. Tag folksonomy == secret sauce
✤ The tagging process is the secret of OSM (IMO!)
✤ Tagging conventions promote innovation but balance with
standardization
✤ OSM has a great community that thoughtfully explores tagging
alternatives
✤ A rich and useful taxonomy (err, folksonomy) has been created

64. Tips for editing
use minimal
points
stay parallel

65. Tips for editing
Be sure to connect
Find the average
(GPS is often wrong!)

66. The Key is Community
✤ Mailing list
✤ Wiki

67. Technology:
✤ More Tech stuff: REST API (get data at real URLS with HTTP GET
and PUT requests) / Runs on Rails
✤ Rendering process: from geodata (nodes ways relations and tags) to
maps
✤ Tiles: small map images; cacheable; load fast; sized for optimal speed
(256x256)
✤ Tile naming convention: same used by google maps
✤ Mapnik: Open source Renderer using postgres

68. Party’s over, here comes math

69. Understanding Tiles
zoom 1
zoom 0
... to zoom 18

70. Gets Expensive!
2^Zoom x 2^Zoom
Zoom 0 has only one tile, zoom 2 has 4x4 tiles, Z3 has 8x8, Zn has 2^n x 2^n
tiles (so zoom 18 has 2^18 x 2^18 or 262144 x 262144 or 68,719,476,736 tiles!
... @ 5kB each thats 320 TB just for the one zoom level)

71. URL Conventions
(same as Google Maps)

72. The Architecture

73. The data

74. The data

75. Rendering

76. The End
Thanks!
Chris Blow
http://unthinkingly.com
http://meedan.net

77. Credits
InSTEDD Innovation Lab, Phnom Penh Cambodia
http://instedd.org
Mikel Maron
http://brainoff.com/
Tim Chippy Watters
http://thinkwhere.wordpress.com
http://www.slideshare.net/chippy/geong-presentation-about-openstreetmap-presentation
Harry Wood
http://www.slideshare.net/harrywood/openstreetmap-open-licensed-geodata
The OSM Community & Wiki
http://wiki.openstreetmap.org
Photos are all CC from Flickr.com (via compfight.com)
Original bits of mine are
Creative Commons Attribution 3.0 United States License