2. Location Based Services
● LBS = using geographical context
– Indoor services
– Mobile healthcare
– City information
● Transport
● Traffic
● ...
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3. Geo-tagging
● Def: the process of adding geographical
identification metadata to various media:
– Photo, video
– Web-pages,
– SMS, QR-codes
– files
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4. Terminology
● Tag – tuple <t, L, B, H, data>,
– t – time
– B,L,H – coordinates
– data – text data ~1K
● Channel – classifier for group of tags
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5. Main features of tagging system
● Access to tags
● Classification
● Filtering
● Session and User management
● Massive data processing
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6. Channels and tags
LBS Platform
Tag
Channel
Канал
Channel Tag
Tag Channel
Tag
- time
- coordinates
- data (link) Channel
Filtration
- time
- radius
- figure (2D or 3D)
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7. Geo2tag architecture
clients
Session cache
cache System cache
android
Query engine
JSON
web Session manager
Qt-based backend
HP
database
embedded Cluster/cloud
infrastructure
Indexer BLOBs
Libraries:
jgeo, http_reqs
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8. Development resources
● http://geo2tag.org
● http://india.geo2tag.org
● http://geo2tag.org/index.php/API_description
● https://github.com/geo2tag
● http://geo2tag.atlassian.net
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9. JSON/REST API
Command:
– Service URL
– Function
– Parameters
Example
http://india.geo2tag.org/service/login?{json}
– Json: '{"login":"Mark","password":"test"}
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10. Invoking by curl
$ curl -d '{"login":"Mark","password":"test"}'
http://india.geo2tag.org/service/login
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11. Command security
● Plain commands (version, build,...)
● Session management
– login
– closeSession
● Authorized commands
– With session token
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12. Session workflow
● Check version
● Acquire session token
● … R/W tags, channels
● Close session
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13. Login
● /login
– login
– password
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14. User management
● /addUser
– login
– password
– Email
● /deleteUser
– login
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15. Channel Management
● /addChannel
– name
– description
– url
– radius
● /owned
● /subscribe
● /subscribed
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16. Working with tags
● /writeTag
– channel
– description
– {coordinates}
– time
– title
● /loadTags
– latitude
– longitude
– radius
–
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17. Contacts
geo2tag-maintainer@fruct.org
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