Tartan-ify visualises the similarities within a single piece of music in a self-similarity matrix.
This was inspired by Song Sim and I built it (but since extended it) at Hackference. You can find the code for Tartan-ify on GitHub.
Firstly, all of the processing happens in your browser.
Tartan-ify divides the music into segments and compares each segment against every other segment. The comparisons are shown in a matrix with both axes donoting time and the colour denoting the difference between the segments at those times.
Tartan-ify does the comparison by analysing the spectrum of each segment using a Fast Fourier Transform, and then taking the sum of the difference of the power of each frequency between the segments.
To use Tartan-ify, select a piece of music and then click Tartan-ify. The tool will detect the song's BPM and use this to split the song into segments and will choose sensible defaults for the visualisation. If the BPM can't be detected, 113 BPM will be used.
The smaller the segments and the longer the song, the longer it will take to generate the visualisation.