Created a program in MATLAB that analyzed Guitar tones, and plot them to the grand staff. Created a library of all possible tones on the guitar staff. Programmed a MATLAB GUI to perform a fast Fourier transform (FFT) on the selected musical tone, and plot the note in the time domain, frequency domain, and the FFT. Designed an algorithm to correctly select the input notes by using the first peak of the FFT against a sampling database. Then created plotting system to correctly plot the note to the Grand Staff.

1. William Fackelman & Joseph Young
Digital Signal Processing Design

2. The Premise
 Our goal was to achieve a functional
GUI that would display sheet music from
an audio input from a guitar utilizing
what we have learned in digital signal
processing
 We were able to accurately display the
46 notes of the Standard tuning guitar
scale.

3. Theory
 Musical notes
are categorized
by the frequency
at which they are
played.
 This can be
utilized to identify
the notes from
their frequency
response.

4. Sheet Music
 Sheet music is written based off the Piano
 7 full octaves; Guitar covers about 4
 46 notes on the guitar used
 The full octave has total of 12 notes
 A-G, with sharps (#) on every note but the B and the E

5. The Audio
 All 46 audio files were recorded using
Garageband.

6. The GUI
 5 Buttons
 3 Graphs
 Numerous
Info Boxes
 1 Grand Staff

7. Song Select Button
 Declared global variable ‘song’
 uigetfile command
 Set all strings
 Reset all graphs with cla command

8. Play Song Button
 Declared global variables ‘song’, ‘x’, and
‘Fs’
 Created if statement
 Two error dialogs: loading music file and
warning to stop music
 Audioread function to set x as
magnitude and Fs as frequency
 Set info strings

9. Stop Song Button
 If statement to check if song is playing
 Error dialog to tell user music must be
playing to stop it
 Set info strings

10. Analyze Button – Time Domain
 Global variables ‘x’ and ‘Fs’
 Calculated the length of original signal
with length(x)
 Plotted x vs. 1:n/Fs

11. Analyze Button – Frequency
Plot
 Used fft to transform original signal into
frequency domain
 Plotted the absolute value of the fft from
0 to the Nyquist frequency with an
interval of Fs/ length of x
 Found the maximum coordinates of the
plot

12. Analyze Button – Frequency
Peaks
 This is the same plot, but with peaks
marked
 Used findpeaks function to analyze the
absolute value of the fft.
 It located any peaks greater than 500 in
magnitude
 Found the minimum values for the peak
to find the true frequency

13. Analyze Button – Grand
Staff
 Created Grand Staff with plot function
 Utilized if, elseif, else statements to give
the ranges of the frequencies of the 46
notes
 Used hold on and image function to
insert whole notes and clefs on same
display as the Grand Staff

14. Export Button
 Used getframe function to take data
from grand staff axis
 Used imwrite function to write the image
to the current folder as Score.jpg

15. Advancements in the Future
 Multiple single notes
- Audio segmentation to determine start
and stop of each note and how many were
played in the file
- Create a for loop using how many notes
were played in the file applied to the if
statement per each segment
 Chords
- Recording all combinations
- Determining new frequency
 Tablature