Pima County Department of Transportation
Geographic Information Services Division
Developing GIS for the Web
Methods for Publishing Spatial Data on the Internet
Real-Time Maps and Images
Real-time maps and images are a step beyond the
real-time map browser category.
Real-time maps use online sensors to supply information to the map.
Instead of providing real-time browsing of a static map,
a real-time map is generated on the fly from sensor data.
There may be a lag of a few minutes, but the idea is to show current status.
Real-time images are captured by live video cameras, often called webcams,
communicating to a web server.
They include terrestrial cameras as well as satellite based imaging.
Satellite photos can provide data that is overlaid on a static map.
Webcam techniques include video cameras that are:
- Connected directly to a computer, such as QuickCam from
Connectix.
The web server serves the resulting image file which may be on the web server itself
or on another network connected computer.
- Connected to a frame grabber on a PC such as a Snappy
from Play, Inc. or
GrabIT II
from AIMS Lab.
The image file is served just like the first case.
- Integrated with its own web server hardware and software.
This type of camera has it's own web address (URL).
- Integrated with a modem so it can be called periodically by a web server.
The EarthCam Internet Camera
is an example of this type.
Examples of real-time maps: