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== Background ==
 
== Background ==
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On February 26, 2012, neighborhood watch coordinator, George Zimmerman, shot Florida teen Trayvon Martin. There are many conflicting accounts about the circumstances that led up to the shooting, including the possible injuries of Zimmerman. Key evidence in this case was an audio recording of a 911 call made by a neighbor that captured screams and gunshots from the incident. Because of the relatively poor quality of the recording and the ambiguity of the screams, there was intense debate during trial as to which party (Zimmerman or Martin) was the source of the screams. Both the defendant and the persecution had experts attempt to improve the quality of the audio in the call in order to demonstrate that their client was the source of the screams and, therefore, being attacked.
  
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The goal of this exercise is to improve the quality of the screams in the background of the call in order to obtain a better-informed view of the events that transpired right before Martin was shot. The quality of the audio will be improved through simple noise filtering in MATLAB, as shown in the following sections.
 
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== Filtering of the Signal ==
 
== Filtering of the Signal ==
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== Sources ==
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http://www.washingtonpost.com/wp-srv/special/nation/last-minutes-trayvon-martin-911-calls/

Revision as of 22:19, 20 April 2017

Audio Filtering of the Trayvon Martin Shooting 911 Call

by Marlow Rumreich


Background

On February 26, 2012, neighborhood watch coordinator, George Zimmerman, shot Florida teen Trayvon Martin. There are many conflicting accounts about the circumstances that led up to the shooting, including the possible injuries of Zimmerman. Key evidence in this case was an audio recording of a 911 call made by a neighbor that captured screams and gunshots from the incident. Because of the relatively poor quality of the recording and the ambiguity of the screams, there was intense debate during trial as to which party (Zimmerman or Martin) was the source of the screams. Both the defendant and the persecution had experts attempt to improve the quality of the audio in the call in order to demonstrate that their client was the source of the screams and, therefore, being attacked.

The goal of this exercise is to improve the quality of the screams in the background of the call in order to obtain a better-informed view of the events that transpired right before Martin was shot. The quality of the audio will be improved through simple noise filtering in MATLAB, as shown in the following sections.


Filtering of the Signal

Source for original audio: https://www.youtube.com/watch?v=AYxJieDtLo0


Sources

http://www.washingtonpost.com/wp-srv/special/nation/last-minutes-trayvon-martin-911-calls/

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