Thursday, December 15, 2011

FCC calls for quieter commercials, but how?

In the news recently is the so-called "CALM Act" (Commercial Advertisement Loudness Mitigation Act), which will force TV and cable broadcasters (specifically, multichannel broadcasters) to make advertisements and content be the same volume.

The problem of blaring commercials, the TV equivalent of the loudness wars, have been going on for some time, but with newer technologies, including digital broadcasting, it has gotten worse. The fundamental issue is that advertisers want to be heard, so they want to be louder than their competition (the program material). However, it's not just a matter of submitting content with higher volume -- broadcasters, whether analog or digital, have limits to the maximum volume they transmit. Instead, they use recording tricks called compression and limiting to boost the average levels of their recordings while keeping the maximum just within limits. The result is a commercial that sounds louder that the program.

While digital technology has made it possible to take this loudness to an extreme, digital distribution has also provided one part of the solution: each piece of program material can be pre-marked with loudness information using a standard called A/85 rp which is used by the consumer's television to determine playback volume.

The trick is to accurately determine the loudness of the material, so that the A/85 tags can be correctly applied. As it turns out, this is no simple task. The ear is more sensitive to some frequencies than others, and you don't want to use simple averaging because then long periods of silence would allow commercials to get away with short loud segments that were disproportionately loud. To get around these issues, A/85 rp recommends the use of a well researched standard called ITU-R BS.1770 (which may be more familiar from the EBU metering and normalizing standard which uses it, EBU R 128). The ITU standard allows the measurement of loudness that very closely matches human perception of loudness, and offers recommendations for use in live, short and long form content.

Will the system be gamed? Perhaps content creators will find some way to trick ITU measurement system to make their content appear less loud than it really is, but even if they do, it seems unlikely that they will be able to game the system anywhere near as well as they currently do.

How will the FCC know if the system is working, and which broadcasters are using the system? They will rely on the public to call-in complaints. Of course, since this has, for years, been the number-one complaint they have received, I don't anticipate too much difficulty there.