u/DanielZaidanin r/C_Programming • Recommends
On “Audio visualizer using SLD2 help”
Sound (after decompression) is store in a bunch of samples. Usually 44100 samples per second, but 48000 is also common. The sample is usually a signed 16-bit integers but other types can also be used.
After you understand that (and see in your code how it's structured) it becomes an easier data-transformation task.
A good sound reference tutorial is this video: [video
I hope that helps you a bit. ;)