Procedural Sound Design, and its impact on games.

A look into procedural sound design, its uses and flaws and why should sound designers should care about it.

In games sound is broken up into two categories, Diegetic and non-diegetic sound. Non-Diegetic are those that do not originate from the world that game is set within such as the games composition or a narration. Diegetic sounds however are sounds are those that emanate from or are created in the world the game is set within for example some spoken dialogue or a gunshot. Because of these differing traits, Diegetic audio emanating from the players world should be aimed to be created in the most realistic and immersive way possible. This in the past has been a hard task for sound designers as problems such as the repetition of audio is quite common in games such as this iconic example below taken from Bethesda's Skyrim.

Of course this problem doesn't only apply to dialogue but also to combat, foley and of course ambience.

What is procedural sound design?

Procedural sound design (not to be confused with procedural sound, which often shares principles) is maximising the use of pre recorded sound (usually ambience of foley), by applying and automating effects blending and mixing sounds to create an ever evolving and unique experience every time. In short, Procedural sound design is audio that is forever changing to create a unique experience to the listener. Being able to create randomised yet consistently accurate audio to use for video game foley and ambience is an invaluable tool to creating great accurate diegetic sound to immerse a player in any virtual world.

Why use procedural sound design in games?

Firstly, as previously mentioned, procedural sound design allows for audio that is consistent enough that sounds will not start becoming unrealistic for the world, yet vary enough so that sounds can keep a player interested and entertained reducing "listener fatigue". Both of these factors combine to create an immersive world. However another great benefit to procedural sound design is that it allows creators to save precious processing power and save space as less audio assets are stored. This is an advantage for both players and creators as it allows creators to reduce the total file size to run a game meaning publishers can save on printing to blue ray disks when releasing for console and players acquiring the game via digital download will get a quicker download to run the game.

Disadvantages of procedural sound design

While processing power is becoming increasingly powerful on new high spec Pc's and consoles, running games is still an extremely intensive process, especially on Pc's not purposely built for this purpose. Stacking procedural generation on top of this processing power can slowly stack up meaning this only adds to the issue of lower grade Pc's and old consoles not being able to run it. On top of this computerised procedural audio may not always share the same quality audio depth that a realistically recorded and edited bespoke audio file may have.

Examples of Procedural sound design

Popular video games are already implementing these techniques, one of the biggest releases to use these techniques are Rockstar. Rockstar use their own game engine the "Rockstar Advanced Game Engine" or "RAGE" already has an advanced system set up for creating procedural sound design in games. The system uses a custom interface that allows assets and digital synthetises to be dropped in and expanded on to the designers likes. This tool can be seen in the video linked bellow where Alistair MacGregor, Lead audio programmer at Rockstar North, talks about its uses and benefits. https://www.youtube.com/watch?v=L4GuM15QOFE

Conclusion

The use of procedural sound design is a great asset to the creation of sound in video games and no doubt will bring a plethora of new techniques and content into the world of sound in video games.