This a project for making a learning app for drum students.
Heads up! This project is folded here and is being continued on bitbucket!
At the moment there are the functions play_from_file (which plays an existing WAVE file) and record_to_file (which records from Default Audio Input and writes it to Disk as WAVE file). It can be compiled with gcc -o test main.c -lsndfile -lportaudio -include audioio.c.
You need
- portaudio (http://www.portaudio.com/)
- libsndfile (http://www.mega-nerd.com/libsndfile/)
At the moment you can load the Python script interactive.py and you'll get in a loop where you can
- record audio (via PortAudio)
- play this back (via PortAudio)
- real-time spectogram plotting
- time-stretch it (simple, pitch-changing, by just interpolating the audio signal)
- writing it to hard disk
At the moment you need
- Python (http://www.python.org/)
- PyAudio (http://people.csail.mit.edu/hubert/pyaudio/)
- NumPy/SciPy (http://www.scipy.org/)
- PyQtGraph (http://www.pyqtgraph.org/)
In the folder time_stretch_tests there are tests for time stretching. The original file ionisation_orig.mp3 is a small excerpt from Edgar Varèses Ionisation. The stretched files are twice as long, i.e. half tempo. (The files have been converted to mp3 afterwards via lame infile.wav outfile.mp3 -V2.)
ionisation_dirac3le.mp3used DIRAC3 LE (http://dirac.dspdimension.com/)ionisation_interpolated.mp3is just an interpolation the signal withdrumapp_tools.timestretch, so the pitch is an octave higherionisation_soundtouch.mp3used SoundTouch (http://www.surina.net/soundtouch/)