mapping

1. A L I A S “ C O M P U T E R C A R T O G R A P H Y ”
DIGITAL CARTOGRAPHY

2. Digital Cartography defined…….
Digital mapping (also called digital cartography) is
the process by which a collection of data is compiled
and formatted into a virtual image.
OR
The generation, storage and editing of maps using a
computer

3. HISTORY
The revolution of cartography is caused by the
persistent use of electronics and in particular
computers.
Society and cartographers have been using computers
for decades but today computers individualized
rather than institutionalized
Analog cartography was technically demanding and
not available to society at large, since the mapping
public did not have ready access to analog mapping
technologies their ability to create mapping products
was rather limited

4. Transition to Digital Cartography
This however is not true in the context of digital
cartography.
Electronic mapping systems are available to anyone
with a desktop computer making it easy for even
‫۔‬non-specialists to create cartographic products

5. Advantages of D.C over A.C
 Storage Medium
 Editing / Updating
Updating a single feature can easily be achieved by simply
selecting that feature and manipulating it according o users
desire. A software enables a user to easily remove, add ,
delete or even edit a features spatial and non-spatial
attributes without having to create the map again from
scratch.
 Data Access:
With the advent of computer cartography access to cartographic is
not limited to only professionals but any layman having access to a
desktop computer can easily produce maps.
Digital Databases
•Spatial and non-spatial
data

6. DIGITAL DATABASES
A digital database allows storage of spatial and non-
spatial properties of objects in an organized effective way.
Printed maps of yesterday have now been replaced my
digital databases.
Spatial Data:
Any physical object on earth that has some positional values
Non-Spatial data:
All the non physical characteristics of spatial objects e.g. name , length ,
Height , Phone number are known as non-spatial or attribute data.

11. Editing

15. Processes
 Data Collection
 Data Manipulation
 Data Analysis : Added Advantage of Digital
Cartography
 Data Representation

17. Data Collection
 Primary Data Sources
 Remote sensing
 Aerial photography
 GPS
 Secondary Data Sources
 Scanning
 Digitizing

18. Remote Sensing
Remote sensing is the acquisition of information
about an object or phenomenon without making
physical contact with the object. In modern usage,
the term generally refers to the use of aerial sensor
technologies to detect and classify objects on Earth
(both on the surface, and in the
atmosphere and oceans) by means of propagated
signals
(e.g. electromagnetic radiation emitted from aircraft
or satellites)

21. Aerial Photography
Aerial photography is the taking of photographs
of the ground from an elevated position. The term
usually refers to images in which the camera is not
supported by a ground-based structure. Cameras
may be hand held or mounted, and photographs may
be taken by a photographer, triggered remotely or
triggered automatically.

24. Photogrametry
Photogrammetry has played a very important role in
mapping. In earlier times the most commonly used tool
was plane table for land-use mapping now
Photogrammetry is the practice of determining
the geometric properties of objects from photographic
images.
Photogrammetry is as old as modern photography and
can be dated to the mid-nineteenth century.
In the simplest example, the distance between two points
that lie on a plane parallel to the photographic image
plane can be determined by measuring their distance on
the image, if the scale (s) of the image is known
methods of Tachometry are used.

25. Global Positioning System
The Global Positioning System (GPS) is a space-
based satellite navigation system that provides
location and time information in all weather
conditions, anywhere on or near the Earth where
there is an unobstructed line of sight to four or more
GPS satellites.

27. Scanning
“Process of converting
analog data into a digital
form”

28. Digitizing
The art of converting features into point, Line or
polygons depending upon the spatial dimension of
the spatial object.
In order for a map to be edited and updated it needs
to be digitized in the form compatible with the
software.

30. Data Analysis
Analysis of data is a process of inspecting,
cleaning, transforming, and modeling data,
suggesting conclusions, and supporting decision
making.
In computer cartography desired results can be
obtained by querying the spatial databases and
applying spatial analysis tools.

33. GIS as a tool for Digital Cartography
GIS is a collection of hardware software and people
Geographic information system is a computerized
system that facilitates with the phases of data entry,
data analysis and data presentation

34. Data Representation

37. THANK YOU!