Download Problem Statement - University of Wisconsin–Madison

Sound Conversion
for Hearing Loss
Patients
using Texas Instruments DSP chips
Advisor: Dr. Thomas Yen
Jack Ho – BSAC
Kuya Takami – BWIG
Nathan Werbeckes – Leader
Joseph Yuen – Communicator
Hearing Loss
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Conductive
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In middle or outer ear
Wax, infection, foreign objects
Dampens all sounds
Sensorineural
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Lose high frequency sounds
Amplification no help
Sensorineural Causes
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Birth defect
Disease
Medications
Loud noises
Brain tumors
Head trauma
Aging
Sensorineural Prevalence

10% of US pop.
(31.5 Million)
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~3 / 1,000 birth
defects
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65% below age 65
Examples
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What they hear
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What we hear
Problem Statement

High frequency hearing
loss
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Normal human hearing
range
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10-20,000 Hz
Speaking range
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Up to 10 kHz
QuickTime™ and a
decompressor
are needed to see this picture.
Problem Statement Ctnd.
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Texas Instruments
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C5509 DSP
Shift/compress frequencies
Using DSP to process signals in real time
 Frequency scan
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Aesthetics
Fashionable
 Bluetooth Hands-free Device Look-alike
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Block Diagram
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Electrot Condenser Microphone
TI Fixed Point DSP (TMS320VC5509)
Digital to Analog Converter
Preamp and speaker
Audio Signal Processing Method
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Audio timescale-pitch modification
Resampling
 Phase Vocoder
 Pitch Scaling (Transpose)
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What we hear
What our device will sound like
What they would normally hear
Audio Signal Processing Method
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Resampling
Audio Signal Processing Method
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Pitch Scaling
(Transpose)
Future Work
(This semester)
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Build Platform
Learn development kit
Write code
Test
Future Work
(later semesters)
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Convert all speech sounds to hearing fovea
Different modes for different environments
Small enough to resemble blue tooth
headset
Good at sound localization
Psychoacoustics
References
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http://www.asha.org/public/hearing/disorders/
http://www.nidcd.nih.gov/health/statistics/hearing.asp
http://www.nidcd.nih.gov/health/statistics/hearing.asp
http://static.howstuffworks.com/gif/hearing-2.jpg
http://hearingblog.files.wordpress.com/2007/08/hearing_aids_bigger24424_1.jpg
Questions?