Loudness In Game Audio

Finishing up Loudness Month here at Designing Sound I asked the good folks at Audiokinetic (makers of Wwise), Firelight Technologies (makers of FMOD) and G.A.N.G. IESD about what is happening in game audio in regards to loudness metering.

From the G.A.N.G. IESD Committee:

“Loudness and monitoring levels have been very high on the IESD’s agenda since the the organization was formed. We see independently produced recommendation documents of this nature as essential for everyone in the industry, from bigger developers to indie studios and, of course, students, or those new to the field of interactive sound.

We had previously, and quickly, worked on a version 1.0 document, which is available on the discussion boards within the GANG IESD website. The focus of this early work was on establishing listening levels (establishing the 79dB home entertainment levels, rather than 85dB theatrical levels, which some developers had been mixing to), and offering a checklist and advice on the more commonly made mixing pitfalls. When Garry Taylor and his group at Sony approached the IESD last year with his Sony paper on loudness levels, we were all on-board very quickly and knew that this was something big. The co-chairs (Kenny Young, Scott Selfon, Alex Brandon and myself) quickly assembled a sub-committe of leading game sound mixing experts (made up of major studio/publisher, and independent contributors) to look at the Sony recommendations and to consider adopting them on a wider level. We soon discovered that Microsoft and Nintendo were also in-line with recommending these same levels and measurement techniques for their first party titles. This made it pretty straightforward to create and agree upon a supporting IESD recommendation document that could confidently suggest numbers for all current-gen home entertainment consoles.

The version 2.0 document, which is intended to be solidified and released in time for GDC this year, adjusts the 79dB monitoring levels to accommodate the ATSC A/85 document, suggesting changes to monitoring levels based on volumetric measurements of the monitoring environment. The loudness recommendations themselves are absolutely in-step with the Sony document in adopting the ITU-R 1770-3 algorithms for measuring loudness over a minimum of 30 minutes of representative gameplay (-23 LUFS, tolerance of +-2dB). True Peak not north of -1dBFS (DB below a full-scale sample).

The next step for the group is to publish a 2.1 version of the document that recommends numbers on iOS and Android devices as well as web browser, though again, the group at Sony has already done some great work in this direction with their -18 LUFS recommendation for the Sony Vita.

The IESD co-chairs are: Kenneth Young, Scott Selfon, Rob Bridgett & Alexander Brandon

The IESD committee consists of Lin Gardiner, Damian Kastbauer, Gordon Durity (EA), Garry Taylor (Sony), Scott Petersen (Nintendo), Tom Hays (Technicolor) and Kristofor Mellroth (Microsoft)”

 

From Simon Ashby at Audiokinteic:

-What is your current (if any) implementation of loudness metering in your product?

[SA]: Currently, Wwise supports Peak meters on mixing busses and on the master bus. There is also a meter effect supporting Peak and RMS that can be inserted on busses, but the primary use for this meter is to monitor the signal going through a bus and for side-chaining other busses.

-Are there any future plans to implement loudness metering (or more types of metering) in your product such as BS.1770 metering specifically?

[SA]: Wwise 2013.1, which will be released this Spring, contains a loudness meter compliant to ITU-R BS.1770-3 and EBU R 128 standards. The meters show the Integrated, Short-term and Momentary values as well as the loudness range. Furthermore, momentary and short-term values are displayed as graphs over time in the Performance Monitor view, which greatly helps spotting problematic moments in a game. True Peak metering is also available in Wwise 2013.1.

-What do you see as the future of loudness metering in game audio and what is your opinion of a standard loudness specification similar to what TV and Film has versus a suggested loudness for Game?

[SA]: Personally, I think the game industry should adopt a standard for loudness specification. I would tend to look at TV series as authored for DVD (e.g. without any additional compression added by the broadcaster) as a the starting point for that specification. It makes sense to follow this lead as the content and the playback environment (e.g. the living room) of console games and TV series are typically the same.

Now, some producers and audio directors are playing the loudness war like the music industry started 20 years ago. So, the fastest way to get all game developers embracing loudness specifications would be through the manufacturers (Nintendo, Sony, Microsoft) to impose loudness guidelines as currently done by broadcasters. If suddenly you couldn’t ship a game because the loudness was too hot, you bet people would start looking at their meters and hire mixers if needed to ship the game within the specified range.

 

From Gino Bollaert at Firelight Technologies:

-What is your current (if any) implementation of loudness metering in your product?

FMOD Studio displays real-time RMS and peak metering across all tracks in both the multi-track editor and the mixer when connected live to the game. Other loudness measurements such as K-weighted metering aren’t yet available, however the framework for supporting different standards is already in place and we are currently working on providing multiple metering options to the user.

-Are there any future plans to implement loudness metering (or more types of metering) in your product such as BS.1770 metering specifically?

Yes, we have started implementing the full BS.1770 spec and we expect both short term loudness and overall loudness measurements to be available in Studio within a few months. We are also working on supporting 3rd-party metering plugins which will open metering right up to other experienced plugin developers and allow users to work with their preferred metering tools.

-What do you see as the future of loudness metering in game audio?

While we think that BS.1770 would be a popular metering standard and great for short-term loudness measurement, we believe users should be able to work with whichever metering tools and standards they feel most comfortable with. Better loudness metering and normalization at the asset level, right through submixes and up to the master mix should not only result in more predictable loudness levels but also save time when it comes to adding or modifying content or snapshots and performing the final mix.

-What is your opinion of a standard loudness specification similar to what TV and Film has versus a suggested loudness?

It’s hard to tell which way to go. An overall loudness standard makes sense for film and TV where the content is known, but this is not so easily applied to a game’s unpredictable content – perhaps a loudness range over a given window duration would be more suitable. Either way, it will most likely take several tries and some finessing before the industry reaches a consensus, and as audio middleware developers, our responsibility is to equip our users with the tools they need to meet whichever loudness standards have been decided on. So we’ll continue to follow this discussion very closely!

 

You can also learn more without reading by listening to the Game Audio Podcast which has a fantastic episode about game audio loudness which can be found here. Special bonus: the episode guest stars our own Shaun Farley. (In addition to Tom Hays from the above IESD committee).  Super special thanks to Rob Bridgett, Simon Ashby and Gino Bollaert for helping put together this article.