Chris Kranky

Recent Posts

I can hear you now and soon on mobile – Opus 1.1

Chris KoehnckeChris Koehncke

opusCodec discussions usually stir some deep emotions. It’s like defining the best red wine you’ve ever had. Someone always has had a better one. To improve our communications, I want the audio (and sometimes the video) at a “being there” level. Opus was the selected audio codec for WebRTC (with only minor grumblings) but similar to the data channel, I think a lot of folks drove by this store without really looking at the capabilities of Opus. You can learn until you’re blind here. But the short is Opus is a fantastic real time audio codec which handles crappy networks, is fast and manages with low delay, variable bit rates you control or are controlled by network conditions or variable based upon the content, multiple channels and a whole bunch of variations in IP networks. Opus is more than just for speech – it really shines when handling music and for a movie sound effects supports LFE (Low Frequency Effects). Opus is an entire stereo system in software. You can read about the specifics of Opus 1.1 here (in painful detail). Opus, like most sophisticated codecs, eats up a lot of CPU power. No biggie on a laptop computer. But to be relevant in the mobile world, it will need to be more efficient. Ta da – Opus 1.1 is born. Opus 1.1 introduced new capabilities and re-wrote some of the main engine. The result is 22% faster on encoding (than 1.0) and a whopping 68% faster on decoding. The logical next step is for Opus to be hardware implemented but for now, these improvements mean that likely a forthcoming Chrome for Android will incorporate Opus 1.1 and great sound quality can be had without chewing up your battery. Quiz: What’s the hardest sound to accurately reproduce by a code? Answer: The harpsichord.