MUMT 307
Outline
- Uploading html files
- Basic Unix commands
- Setup sftp client
- Upload files to your home page (lab)
- Spectrum
- Digital filters
- Modifying existing Javascript webpages (lab)
MUMT 307
Upload your html files to music.mcgill.ca
- Open a Terminal / Command Prompt
- Login by:
ssh username@music.mcgill.ca
- Enter password: (case sensitive and there's no echo)
- If you're successful you should see the prompt:
-bashr-3.2$
- Once logged in go to the home directory for your web pages:
cd public_html
- To edit your home page (index.html):
nano index.html
- Or upload files using an sftp client, e.g., Filezilla and CyberDuck
- Change your password using:
passwd
MUMT 307
Basic Unix Commands
- To change directories:
cd
- To go up a directory:
cd ..
- To make a new directory:
mkdir DIRECTORY_NAME
- To list files in a directory:
ls
- To edit a file:
nano FILNE_NAME
- For more information on a command:
man COMMAND_NAME
- For more, see Unix/Linux Command Overview
- For a tutorial on Unix commands see: Unix/Linux Tutorial for Beginners
MUMT 307
Setting up your sftp client
- Download a client: FileZilla, Cyberduck, or Komodo
- FileZilla
- Use "Site Manager..." under "File" menu
- Cyberduck
- Use "New Bookmark..." under "Bookmark" menu
- Komodo
- Use "Preferences" under "Komodo" menu; then Servers
- Create an index.html file and upload to your homepage (public_html)
MUMT 307
Spectrum
- Frequeny domain vs time domain representations of signals
- Demo: Web Audio API Visualizer
- A demo with Web Audio API oscillator
- Additive synthesis for band-limited waveforms
- Square wave: odd harmonics with decreasing amplitude (-6dB) (1/(2n+1)) y = sin x + (1/3) sin 3x + (1/5) sin 5x + (1/7) sin 7x + ...
- Triangle wave: odd harmonics with decreasing amplitude (-12dB) (1/(n*n)) y = sin x + (1/9) sin 3x + (1/25) sin 5x + (1/49) sin 7x + ...
- Sawtooth wave: all harmonics with decreasing amplitude (-6dB) (1/n) y = sin x + (1/2) sin 2x + (1/3) sin 3x + (1/4) sin 4x + (1/5) sin 5x +...
- DFT and FFT: Fourier's theorem
- Gary's notes on Spectrum
MUMT 307
Digital Filters: Simple examples
- Sample inputs (SF: sample frequency):
- a @ 0Hz -> {1, 1, 1, ...}
- b @ SF/2 Hz -> {1, -1, 1, -1, ...}
- c @ SF/4 Hz -> {1, 0, -1, 0, 1, 0, -1, ...}
- Case 1: y(n) = x(n) + x(n-1)
- a -> {1, 2, 2, 2, ...}
- b -> {1, 0, 0, 0, ...}
- Case 2: y(n) = x(n) - x(n-1)
- Case 3: y(n) = x(n) + x(n-2)
- Case 4: y(n) = x(n) - x(n-2)
MUMT 307
Digital Filters: Simple examples
- Sample inputs (SF: sample frequency):
- a @ 0Hz -> {1, 1, 1, ...}
- b @ SF/2 Hz -> {1, -1, 1, -1, ...}
- c @ SF/4 Hz -> {1, 0, -1, 0, 1, 0, -1, ...}
- Case 1: y(n) = x(n) + x(n-1)
- a -> {1, 2, 2, 2, ...}
- b -> {1, 0, 0, 0, ...}
- Case 2: y(n) = x(n) - x(n-1)
- a -> {1, 0, 0, 0, ...}
- b -> {1, -2, 2, -2, ...}
- Case 3: y(n) = x(n) + x(n-2)
- Case 4: y(n) = x(n) - x(n-2)
MUMT 307
Modifying existing Javascript webpages
- Download the main source
- Inspect the main source to look for dependent files (.js, .css)
- Download the dependent files to appropriate places
- Edit the main source code to reflect the locations of the dependant files
- Test it on the local file system with the Error/Javascript Console
- Upload the files to the remote web server
- Test the webpage
- Try with the Web Audio API Filter
- Try with the Web Audio API Visualizer