UCF Noise Map,
an Android Application
Project Presentation
Cindy Atherton and Deepa Shinde
Project Plan
 Introduction to Sound Pressure Level(SPL)
 Mobile splMeter App

◦ Capturing SPL
◦ Viewing the Map

Server Side Processing
◦ Using Microsoft MapPoint
◦ Hosting the web page

Conclusions and Future Work
Topics
Provide an Android Emulator app that enables clients to
contribute data and download a map from the server:
 Client-server communication in Android Emulator will
illustrate network communications
 Clients will have the ability to capture sound files and
process intensity levels (in decibels) showing how
Android handles file and sound processing and how
the Emulator simulates sound sensors
 Clients can view temporal maps of noise
 Server compiles and stores data as well as produces
temporal maps from the client data
 Maps display noise levels as temporal distribution by
displaying the areas on the map based on color-coded
sound level intensity scale
Project Plan
Introduction to Sound Pressure Level
Sound pressure is the local pressure
deviation from the ambient (average, or
equilibrium) pressure caused by a sound
wave.
 Sound pressure level (SPL) is a
logarithmic measure of the effective
sound pressure of a sound relative to a
reference value.
 SPL is measured in decibels (dB) above a
standard reference level.

Definitions

The decibel expresses the level of a given
sound in terms of the ratio of the meansquare pressure of the sound to a
reference mean-square pressure.
◦ pref is the standardized reference pressure
◦ prms is the rms (root-mean-square) pressure of
the sound under consideration
SPL Computation
Sound Levels
http://www.mallory-sonalert.com/Articles/TechAppGuides/Decibel Sound Level Scale.pdf
Mobile splMeter App
The splMeter Android App
http://code.google.com/p/splmeter
 SPL Meter is a Software Based Sound
Pressure Level Meter that runs in android
OS.
 Copyright (C) 2009 Hashir N A
hashir@mobware4u.com

Modified from original splMeter
GUI
Contribute
Reading
User Activities
View Map
Contribute
Reading
Start
Listening
Record &
Calculate SPL
Submit
Reading
Write text
file to SD
card
Contributing Readings
Contributing Readings
View Map
Access website
Download map
in GIF format
Display map
Viewing the Map
Viewing the Map
Server Side Processing






Very simple to use
Readily available via the MSDN Academic
Alliance (Free)
Accepts text files as input to update existing
map (no need to parse files)
Enables users to create their own custom
data ranges and corresponding visual
representations
Outputs images in GIF format, which is
supported by Android
Exports maps as HTML files
Reasons for using MapPoint
Latitude
28.600523
28.601936
28.602922
28.602235
28.601547
28.600954
28.600605
28.600681
28.601293
28.600916
28.600106
28.601170
28.602875
28.604608
28.603751
Test Data
Longitude
-81.197916
-81.200405
-81.198505
-81.199706
-81.200704
-81.199363
-81.199213
-81.199073
-81.199062
-81.197775
-81.201466
-81.201498
-81.201079
-81.198762
-81.200457
Decibels
110
150
70
20
65
65
65
40
90
38
60
80
50
20
70
Server Side: Microsoft MapPoint
Custom Data Ranges
Server Side: UCF Noise Map Site
http://www.cs.ucf.edu/~catherto/UCF%20Noise%20Map.htm

The splMeter App currently

Drawbacks

To Do
◦ Runs on the Android Emulator
◦ Allows users to contribute SPL readings
◦ Allows users to view a current noise map of the UCF campus
◦ The Emulator has no GPS location sensor, the latitude and
longitude had to be hardcoded
◦ Input to MapPoint and upload of the HTML file to the
Internet are done manually
◦ We are investigating writing an application in Visual Basic
that will automate processing on the server side
◦ Finish paper
◦ Clean up code and GUI
Conclusions and Future Work