UPDATE: Here is the “pitch tracking” Pd patch I made in lecture using [fiddle~].
Puredata (PD) is free, open sources, and available in several flavors:
- Puredata (Pd) “vanilla”, untainted program from Miller S. Puckette
- Purr-data/PD-L2Ork, a Pd distribution for Virginia Tech’s Linux Laptop Orchestra (L2Ork)
There are dozens of tutorials and help systems available. I suggest this video series by Dr. Rafael Hernandez, for starters, as well as Pd’s own built-in help system. A useful forum on Pd, including examples provided by users can be found here.
A deeper history of Pd from Miller Puckette himself, including its origins in the earliest computer music languages can be read here.
Max/MSP is commercial software, similar to Pd having the same original source code. Max is available as a 30-day trial download on the Cycling74 website. Cycling74 was purchased by Abelton in 2017.
As with Pd, there are a multitude of tutorials available, including a help system built into the software itself. Some example projects using Max can be perused here.