Download Location Aware Music Player

Location Aware Music Player
By
Kevin West
David Zhao
Basic Concept
 A music player that knows where you are.
 Play different music in different parts of your
house.
 Finish the song you are listening to right as
you reach your destination.
 Great for students traveling in between
classes, who hate being interrupted.
Basic Scenario
 People listen to different types of music
when they are at different places.
 A person may want to listen to heavy music
when he’s working out at the gym.
 He may want to listen to classical music
when he’s studying in his room.
Basic Scenario (continued)
Solution:
 Detect the current location and play different
types of music according to the location.
Basic Scenario (continued)
 A student is listening to his mp3 player
between classes. By the time he reaches his
next class though, he still has over a minute
to go on his favorite song. He’ll have to stop
it to listen to the professor.
 What if the song had already ended?
Basic Scenario (continued)
Solution:
 Figure out how much time until user reaches
next destination. Alter the speed of music
playback subtly to finish the track when the
user arrives.
Architecture - Components
 Music Player
 Location-Detection: Placelab
 Location analyzer
 Sound speed adjuster
Expected Effort
Pieces to be built:
 Placelab Analyzer: Interpreting Placelab data
to determine a location, and a velocity
towards next location.
 Audio Speed Adjuster: Speeding up and
slowing down the audio stream without
significant loss of quality.
Expected Effort (continued)
Minimum Functionality:
 Determining a location and playing the
correct music.
 Determining the velocity and adjusting the
stream to finish as the user gets to his
location.
Expected Effort (continued)
Desired Functionality:
 Fading in between different streams as you
enter a new location.
 Adjusting the audio speed in such a way that
the change is invisible to the user.
Unknowns
 How accurate is Placelab? Can we get a
good velocity reading?
 Can we change the audio speed without pitch
shifting or losing significant quality?
Algorithmic Design
 The Problem: Given a set of songs with
specific lengths, minimize the speed changes
in the audio.
 Example: Song 1 = 3 min, Song 2 = 3 min,
We will arrive in 5 min. We can adjust Song
1 to be 5 min, or adjust both to be 2.5 min.
Burning Questions
 Will we be able to do speed adjustment of
audio quickly enough to be unnoticed?
 Can placelab provide accurate information
on velocity?
Evaluation
 Performance Tests


Quality of speed-altered sound
Accuracy of estimated arrival time
 Usefulness

How much does the user care for location-aware
functionality?