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This module provides example inputs and outputs of the piano note detection algorithm using our implementation. It also discusses what our algorithm and implementation do well and what they do inadequately.

The culmination of our efforts resulted in a wide array of both achievements and shortcomings. We discovered many detection techniques that could be coded and implemented easily and effectively. Conversely, there were many nuances and non-ideal behaviors exhibited in even the most simple of piano pieces that a talented musician would have trouble detecting, let alone a program in Matlab.


  • High precision in hit detection for reasonably paced songs up to eighth notes
  • High success-rate in note detection for single notes played at a time
  • Effective quantization from frequency to note for well-tuned pianos
  • Very precise note-length determination for all notes actually detected and analyzed


  • Faults in piano and non-ideal behavior can cause anomalies in output
    • Poor tuning causes note-detection errors
    • Residual ringing after key-release can cause notes to appear longer in duration
  • Chord detection, especially in octaves, is imprecise: some overlapping notes escape detection
  • Poor note-hit detection in “busy” songs
  • Overlapping note-hits causes single, held notes to appear as multiple shorter notes


We used many different songs to test our algorithm, but these three examples effectively illustrate the above points. The songs are a chromatic scale starting at C5, Mary had a Little Lamb , and the beginning of Pachelbel's Canon in D .

Each example contains the original recording in the top left, a matrix representation of the generated sheet music on the right, and a computer-generated song playing the sheet music in the bottom left. In other words, the generated music is what would be heard if someone were to play the sheet music we generate.

To read the matrix form on the right, read left to right, then top to bottom. Each row contains a set of notes that are played simultaneously, followed by the length of the note. After playing those note(s), proceed to the next line and play those notes. At no time should two notes from different rows both be played.

C5 chromatic scale
The original recording
The generated music

Here, the melody of this simple scale is deciphered perfectly. The only errors being that the previous notes ring through twice (marked in red), and the last note's length was unable to be determined due to the lengthy silence at the end of the recording (marked in blue).

Mary had a little lamb
The original recording
The generated music

Again, this simple song was deciphered perfectly except for previous notes ringing through (marked in red), and the failure to find the last note's length due to the silence at the end of the recording (marked in blue).

Pachelbel's canon in d
The original recording
The generated music

This song shows the greatest shortcoming of our implementation, which is difficulty detecting chords. Again, note that the melody and the note lengths were deciphered perfectly. However, when the quieter, higher harmony begins to play, it does not get picked up (marked in green). Finally, the repeated F#/Gb2 at the end shows how overlapping notes cause a longer note to appear as two shorter notes.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Elec 301 projects fall 2006. OpenStax CNX. Sep 27, 2007 Download for free at http://cnx.org/content/col10462/1.2
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