Writing music audio files using sine, square, triangular and sawtooth wave
Architecture of the C++ implementation
main()
┌──────────────────────────┐
│ │
│ Write WAV │
│ header │
sigen.cpp │ │
│ │ │
┌──────────────────────────┐ │ ▼ │
│ │ │ │
│ play() Generate │ │ Parse parse() │
│ signals ◄─┼─┼── score │
│ │ │ │
│ │ │ │ │ │
│ ▼ │ │ │ │
│ │ │ │ │
│ filter() A/R filter │ │ │ │
│ │ │ │ │
│ │ │ │ │ │
│ ▼ │ │ ▼ │
│ │ │ │
│ lowpass() Low pass ──┼─┼─► Write │
│ filter │ │ notes │
│ │ │ │
└──────────────────────────┘ │ │ │
│ ▼ │
│ │
│ Insert data size │
│ in WAV header │
│ │
│ │ │
│ ▼ │
│ │
│ Playback │
│ with │
│ system Call │
│ │
└──────────────────────────┘
To use the C++ version:
make simple./simple sheets/<title>.wmusicfor debug mode:
make refresh DEBUG=1./simple sheets/<title>.wmusicThe wave module in the Python standard library provides a convenient interface to the WAV sound format. References: https://docs.python.org/3/library/wave.html https://www.tutorialspoint.com/read-and-write-wav-files-using-python-wave
We can write some music with this module. We also intend to write music from waves with C++.
The playsound module can be used to play the WAV file generated. Run the following command to install it:
pip install playsound==1.2.2Then to run the python script:
./simplest.pyThe simplest.py script in the src folder demonstrates creation of simple monophonic melodies with sine waves and square waves. The song is "Ting Wo Shuo Xie Xie Ni". We would like to add more features to the program to produce chords and more complicated melodies in the future. The simpler.py script is an alternative version of simplest.py, and simple.cpp demonstrates a way of doing it in C++.
TODO list:
- consistent note length
- functional REPL
- triangle wave generation
- polyphony doesn't sound out of tune anymore?
- saw and square waves sounds bad, add LPF to soften it