CALM: How Engineering, Technology Will Dial The Noise Down
As the dust settles regarding the recent passage of the Commercial Loudness Mitigation Act (CALM), technologies aimed at ratcheting down those screaming TV ads are sprouting like mushrooms.
The hyper-annoying commercials with deafening influxes of decibel levels are being toned down via government regulation and a variety of technologies (both old and new), coupled with some engineering acrobatics.
“Digital signal processing is now widely available, so companies can patch together technologies to address noise control, like cards or black boxes between content and broadcast equipment,” says Mike Jude, program manager for Stratecast, a research arm of Frost & Sullivan. “Even with active dynamic ad insertion, it’s not a huge technical challenge. Finesse is the hard part.”
It’s a balancing act for technicians and engineers, he adds: “Like a bell curve, most TV programming is in the middle of the curve. If all the signals are compressed on the high side, the acoustic energy is perceived as being louder. There will probably be a specification for acoustic energy where no commercial can be over it.”
One spec, known as EBU (European Broadcasting Union) R 128, establishes a predictable, well-defined method to measure the loudness level for programming, including commercials. Yet for technology companies like Ensemble Designs, Dolby, Mixed Signals and others, toning down loud commercials in compliance with CALM is all about deft engineering, advancing technologies and an emerging new thought process.
“A new school of thought is for people to de-code ad spots and get the controls right before production and before delivery to cable operators,” explains Cindy Zuelsdors, head of marketing at Ensemble.
Some signals are compressed so much, she continues, that they sound even louder: “We turn down the level to where it can be raised and don’t compress the audio. It’s all part of sound design.”
Ad splicing and software are integral parts of the volume-control process as well. “Splicing was the logical place to address the issue, and software resides in our VIPr product, which doesn’t interface with set-top boxes,” comments Bill Hogan, VP/product management for advanced video products at Arris.
The Arris software has a fast algorithm; the company continuously monitors volume levels and adjusts certain parameters within the bit stream, he claims, and it can make computations quickly.
The challenge, Hogan admits, is staying current with ever-changing technologies: “The landscape of video processing is changing so quickly, it’s a challenge to keep on top of it.”
One way is to look at the network holistically. According to Matthieu Chamik, product manager at Cheetah, “Providers are looking for clarity of the landscape, including ad insertions. We’re taking the CALM Act and algorithms the same way we approach video.”
Service providers also are looking for scalability along with ways to advance the technologies and processes to monitor and measure commercial audio volumes cost-efficiently. “We’re talking to players in the live encoding space for measurements and feedback in real time, and to potentially adjust volumes on the fly,” says Eric Conley, VP/video network monitoring at Tektronix.
In the meantime, concludes Conley, “it’s up to MSOs, broadcasters and other service providers to fix the loudness problem and to reserve the right to re-encode the ad spots to comply with CALM.”
– Craig Kuhl