This is a simple code that follows Prof. Gary Settles' book; Schlieren and Shadowgraph techniques. Nomenclature is also following his book, for the most part. More details on my website: https://zigunov.com/?p=2199
Hope this enables you to see your own sound waves!
Fernando Zigunov (2020). Visualizing sound waves with a Schlieren apparatus (https://www.mathworks.com/matlabcentral/fileexchange/75304-visualizing-sound-waves-with-a-schlieren-apparatus), MATLAB Central File Exchange. Retrieved .