How Does An Audio Visualiser Work?

Sound is very interesting to listen to, especially when it is in the form of music. But we can only listen to the sound. Ever wondered how a thing that is so beautiful to listen to would look like? Is there any way to see sound? Well, most people will tell you that sound can only be heard and can not be seen in any way. But you must not forget that we live in a world of advanced science and technology. Though it is true that we cannot see sound naturally, with the help of technology, we can create systems that can help us see it indirectly! An audio visualiser is one such system.

There are many people in the world who already know about audio visualisers and use them as well. But little is known about how audio visualisers actually work. The truth is that visualisers don’t actually make us see sound. Sound is a vibration created in the medium and you obviously can’t see a vibration. But what visualisers do is to create abstract visuals that change in sync with the sound that it is based upon. Now how the visualisers sync video as per the sound is the main technology behind it. 

When a visualizer plays a song, it analyses its audio data in very tiny time intervals which lie around 20 milliseconds. The visualizer applies a Fourier transform to data of each interval, identifying the frequency information. It then uses those frequency components to regularly update the visual display in sync with the audio input. The programmer determines how the visual display is refreshed in response to the frequency information. For smooth updating of the visuals In sync with the music, the graphics systems must be incredibly quick and lightweight.