1. How Do mp3’s Work By Lauren Howard May 2005

2. MPEG Mp3 files are short for MPEG-Layer3 files. MPEG is short for the Motion Pictures Expert Group. This company works on new breakthrough compressing files. MP3’s are one of them.

3. Algorithms Other than mp3’s, they also work on zip files-file compressions, and gif files- image compressions. These are all called algorithms.

4. Encoding Tools Mp3’s are an encoding tool that basically analyze incoming data, break it down into mathematical equations and discards what isn’t needed.

5. Music to Your ears The Mp3 music is formed into hertz (Hz)which are measured in cycles per second. Humans can hear no higher than 20,000Hz and no lower than 20Hz.Younger people can hear higher than older people.Over time though sensitivity to higher sounds goes away with long exposures to loud noise.

6. Compressions The file format for mp3’s is a music compression system that shrinks the number of bytes in a song. This is called Perceptual Music Shaping.

7. Perception It’s called perceptual music shaping because it uses the the human ear to know what Data to remove from the song.The models used to show human ear examples are called psychocoustics models.

8. What your ears can hear 1 ear One of the examples of what sounds human would hear if the two notes almost sound the same. Undeleted note Deleted note

9. What your ears can hear 2 This is an example of if one note is too high for human ears to comprehend. Undeleted note Deleted note Another badly drawn ear

10. What your ears can Hear 3 This is an example if the note cannot be heard very well. Undeleted note Deleted note

11. Filtering With these and more examples, the mp3 program filters out the notes that are not needed. The song sounds very close to the original, and there is way less data in it than before.

12. Tolerance Levels The user can also set a tolerance level, which,while the mp3 is filtering, tells how much can be removed from the song. The higher the tolerance level, the more specific the mp3 is at removing bytes and the music sounds better.But if the Tolerance level is low the music sounds really bad.

13. The Second Compression After shrinking the notes a compression is used that is called [fi] lossy, because the data that was not lost, is shrunk even more with a compression similar to zip compression( file compression).So it will be easily stored.

14. ID3 Data ID3 Data is the information that tells about the song like the album, artist, the title of the song, the year, the genre, or any extra comments the artist wants to add. ID3 data is attached to the mp3 files that come through the computer.

15. Music for YOU! After the mp3 data goes through this process, the information is put into the computer that asked for it.With the music, you can the put it onto an I-pod or sent it to some on through the internet.

16. Bibliography Brain, Marshall.”How mp3 Files Work.”[online]http://www.how stuffworks.com/mp3.htm, April 2005. Freed, Les.Guide to Home Networking.Indianapolis:Wiley Publishing, 2004.

17. Bibliography Cont. Fries, Bruce and Marty Fries.The mp3 and Internet Audio Handbook.Burtonsville: TeamCom Books, 2000 Hacker, Scot.”Sample Chapter 2: How mp3 Works: Inside the Codec.”[online]http://w ww.oreilly.com/catalog/mp3/chapter/ ch02.html, May 2,2005

18. Bibliography Cont. “How do Mp3’s work?”.[online]http://ww w.units.muohio.edu/psybersite/cybe rspace/mp3issues/work.shtml

19. About the Author Hey! It,s me Lauren. I love Siberian Huskies but I am currently not allowed to have pets.I like to play video games and read manga. I also enjoy ice skating and(no offense)I don’t like roller coasters!