~ Gabber - Visualizing constant-Q transform in the browser
» By Joren on Wednesday 01 March 2023Today I have released Gabber a bit of code to transform audio from the time domain to a constant-Q frequency domain in the browser. To be more precise it does a constant-Q non-stationary Gabor transform. The heavy-lifting is done by ‘the gaborator’, a C++ library by Andreas Gustafsson.
I have compiled the Gaborator library to WebAssembly, added some glue code to bridge the Javascript and WASM worlds, implemented a Web Audio AudioWorkletProcessor
to transform audio in the background and and finally visualized the results via WebGL2.
There is a Gabber live demo below. If you press start and grant microphone access, incoming audio is transformed and plotted onto a canvas. Thanks to WebAssembly and WebGL2 this should run relatively smoothly even on less powerful devices. Please do play around with the perspective slider.
While Gabber is currently a proof of concept, with some attention the library could be used as a front end for browser based music information retrieval applications. My main goal with Gabber is to use it in educational settings to explain the properties of sound, and more concretely pitch, via spectrograms and interactive demos. Also I plan to use it in a browser based tool to extract pitch patterns from music.
The name Gabber, refers to both Dennis Gabor and an infamous, mainly Dutch style of music which was popular when I was young. More information can be found in the GitHub repository: Gabber-High resolution spectral transforms for the web.