This PPT contains the basics of Geocoding. If you are a beginner then it will definitely help you to understand what Geocoding is all about and why we do Geocoding.

1. Optimization of Spatial Database for Enhancement of performance for Forward and
Reverse Geocoding
Akansha Mishra

2.  GeocodingAnd Geotagging
 Introduction to Geocoding
 Why we use Geocoding
 Addressing System
 Addressing System of different Countries
 Different Geocoders
 Levels of Geocoding
 Geocoding Process
 Reference Datasets
 Geocoding Data
 Spatial Database System
 Optimization of Spatial Database
 Spatial Indexing Algorithms
 R-Tree and QuadTree Indexing Algorithm
 Challenges
 Q & A

3. GEOTAGGING
 Geocoding is the process of assigning
latitude and longitude values to address
information.
 The process of gettingAddress data from
Location data (lat/Long) is called Backward
Geocoding.
 Input Address: "642 Arbitrary Lane, Cityville,
MA" or "Miami" or "FIPS county #64623“.
Output Coordinates: "53.645 N, 73.6453 W"
GEOCODING
 Geotagging is the process of adding
geographical information to various media in
the form of metadata.
 Metadata consists of coordinates like latitude
and longitude, it may also include altitude,
distance and place names.
 Geotagging is most commonly used for
photographs. It contains the information about
where the photograph was taken.

4.  Geocoding is the conversion of a human-readable location name into a machine-
processable location such as latitude and longitude.
 Once a latitude and longitude coordinates is assigned the geocoded address can be
displayed on a map or used in geographic search.
 Reverse Geocoding is the ability to find an associated textual location , like a street
address or business name from latitude and longitude coordinates.
Output:
4383 Apple Ct Boulder CO
80301-1745
-105.248599, 40.054337
Input:
4383 Apple Boulder CO 80303
Geocoding
ReverseGeocoding

5.  Geocoding allow operational spatial decisions to be made:
 Where is the Customer? Nearest to which CellTower?
 What is this point inside/close to?
 What is the value/Risk/Danger?
 Delivers Answers to Critical Business needs.
 Facebook Check In:
 Facebook Can use reverse geocoding to auto populate place
address field during Check In.
 Pictures, Status updates and other timeline events have
location tags available.
Spatial ProcessingGeocoding
Business
Decision

6.  An address is a collection of information that describes the location of buildings, apartment,
plot or other structure.
 Address are two types:
 Relative Address: Such As Across the Street, behind the landmark etc.
 Absolute Address: Actual address that contain house no, street name, locality, town, state
and other address Components.
 Components of address are house number/ Apartment number, Apartment Name, Street
number, Street Name, Zip Code and political boundary.
 There is no globally applicable address format exist that works internationally.

7. Australia:
[FLOOR] [/] [APARTMENT]
HOUSE_NUMBER
STREET_NAME STREET_TYPE
LOCALITY
PROVINCE_ABBREVIATION
POSTAL_CODE
AUSTRALIA
Canada:
[UNIT_NUMBER]-
CIVIC_NUMBER
[STREET_NUMBER]
[STREET_TYPE] STREET_NAME
[STREET_DIRECTION]
LOCALITY
PROVINCE_ABBREVIATION
POSTAL_CODE
CANADA
Cameroon:
STREET_NAME
[HOUSE_NUMBER]
LOCALITY
CAMEROON
China:
[BUILDING] [APARTMENT]
[HOUSE_NUMBER STREET,]
[DOUBLE_DEPENDENT_LOCALI
TY,] [DEPENDENT_LOCALITY,]
[LOCALITY]
POSTAL_CODE PROVINCE
India:
[HOUSE_NUMBER]
[STREET_NAME]
[DEPENDENT_LOCALITY] [,
DOUBLE_DEPENDENT_LOCALIT
Y]
LOCALITY - POSTAL_CODE
INDIA
United States:
HOUSE_NUMBER STREET_NAME
[STREET_TYPE]
[STREET_DIRECTION]
[BUILDING] [FLOOR]
[APARTMENT]
LOCALITY
PROVINCE_ABBREVIATION
POSTAL_CODE
UNITED STATES
United Kingdom:
[FLOOR] [APARTMENT]
[BUILDING]
[HOUSE_NUMBER] STREET_NAME
[DEPENDENT_LOCALITY]
LOCALITY
POSTAL_CODE
UNITED KINGDOM
France:
[APARTMENT] [BUILDING]
HOUSE_NUMBER
[STREET_TYPE] STREET_NAME
[DEPENDENT_LOCALITY]
POSTAL_CODE LOCALITY
FRANCE
Turkey:
STREET_NAME STREET TYPE
[DEPENDENT_STREET
STREET_TYPE] [BUILDING]
[[No.] HOUSE_NUMBER
[/APARTMENT]
POSTAL_CODE
[ADMINISTRATIVE_DISTRICT /]
LOCALITY / PROVINCE
TURKEY

8.  Google Maps
 Yahoo Maps
 Bing Maps
 ArcGIS
 Geocoder.us
 MapMarker
 Global Locator
 Address Doctor
 LOQATE

9. Zip Code
Area
Street level Geocoding
----------------------------------------------------------------------
Point level
Geocoding Address Point Interpolation
Zip+4 level
Geocoding
(6+4 Digits)
Zip Level Geocoding
(6 Digits)Zip+4 Area

10.  Point level geocoding:
• Address is matched to the location of the
Building Rooftop
GPS front Door
Parcel Centroid
• Point level geocoding is more accurate than Street level Geocoding.
 Street Level Geocoding:
• Address is matched against a street segment address range.
 Zip Code Level Geocoding:
• Zip code level geocoding returns the centroid of the passed Zip code area.
 Zip+4 Code Level Geocoding:
• Zip+4 is the sub division of zip code.

12.  Reference dataset provides the base data from which the geocoder
calculates, derives or obtains geocodes.
 Linear Based Reference Datasets:
 Roads and Ferries.
 US Census BureauTIGER provide vector line file.
 Polygon Based Reference Datasets:
 Administrative Boundaries and postal Codes.
 Los angels Country Assessor Parcel Data isVector Polygon File.
 Point Based Reference Datasets:
 POIs.
 Australian Geocoded National Address File(GNAF) isVector
Point File.

13.  Most Geocoding Applications work withVector
based GIS Data.
 Vector Data represent features as:
 Discrete Point
 Line
 Polygon
 Vector Data is available in
 TAB Files
 Shape Files
 Cad( AutoCAD DXF & DWG).

14.  A database system that is used to store and query spatial objects:
 Point: a hotel, a car
 Line: a road segment
 Polygon: landmarks
 Spatial databases can perform a wide variety of spatial operations.

15.  Optimizing spatial databases means
optimizing the queries, which requires less
time spent by running the queries before
receiving an answer.
 Spatial Indexing is used to decrease the
number of searches.
 Appropriate Indexes can reduce the Response
time.
 Oracle Spatial uses two types of indexing: R-
Tree and QuadTree.

16.  R-Tree
 QuadTree
 K-DTrees
 K-D-BTrees
 Grid Index
 Z-order
 Octree
 UB-Tree
 M-Tree
 HTM
 Geohashes

17.  Objects(Point, Line and Polygon) are
grouped using the MBR(Minimum
Bounding Rectangle).
 Objects are added to an MBR with an
INDEX .It index geometries in two or
more dimensions.
 R-tree are more suitable for nearest
neighbor search.
 Basic Spatial Operations are performed
much faster using an R-Tree indexing
types.
R1 R2
R3 R4 R5 R6 R7
R8 R9 R10 R11 R12 R13 R14 R15 R16 R17
R7
R6
R2
R1
R17
R16
R14
R15
R
8 R1
0
R
3
R
9
R4
R5
R12
R13
R11
Desired Region

18. 0 1
2 3
10 11
12 13
132
Desired Region
133
130 131
 It divides rectangular 2D regions into
quadrants until we reach at a desired
granularity.
 QuadTree Indexes are preferable when there
is heavy updates activity to the Spatial
Column.
 It can easily integrate into traditional
database.
 QuadTree has its advantages in terms of
more complex type of Queries.

19. Spatial Data
Layer
Primary Filter:
Spatial Index
Data Selection
Secondary
Filter: Spatial
Functions
Result
Optional Filter

20.  Geocoding Accuracy:To correctly identify a
location.
 International Geocoding :
 Address formats vary
 order of the address is often different
 Use of Native languages.
 Use of Multiple Data Sets.
 Sequential Processing
 Inconsistent use of base maps and geocoding
services.