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It’s Opus, it rocks and now it’s an audio codec standard

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Re: It’s Opus, it rocks and now it’s an audio codec standard

#61

Post by lloeki »

kibwen wrote: post #3

Before someone chimes in with that XKCD strip: How does Opus compare to other codecs? Opus is distinguished from most formats for high quality audio (AAC, Vorbis, MP3) by having low delay and it is distinguished from most low delay formats (G.711, GSM, Speex) by supporting high audio quality. It meets or exceeds existing codecs' quality across a wide range of bitrates, and it operates at lower delay than virtually an…

> And here's the coolest part of the article that completely took me by surprise: "The IETF recently decided with “strong consensus” to adopt Opus as a mandatory-to-implement (MTI) codec for WebRTC, an upcoming standard for real-time communication on the web."

Indeed. There may be interesting side consequences for that. The first article comment asks:

> Interesting! Any idea if this will become mandatory to implement for HTML5 audio as well? That’s another area in sore need of a single format that works everywhere.

This means that if a browser supports WebRTC, it has to support Opus, and it then happens that the codec will be available for . Now that does not mean that => Opus support, but it will have a (increasingly with time) high chance to be so.

Re: It’s Opus, it rocks and now it’s an audio codec standard

#63

Post by masklinn »

ZoFreX wrote: post #60
masklinn wrote: post #55

Earlier quoted context omitted.

> Using low bit rate Opus may yield a 3MB file for a song, were as FLAC may end up being 150MB for the same audio. 3MB will get you POTS-quality audio though. Lossless codecs usually compress audio to half the original size (so a 150MB FLAC file — for music — will correspond to ~300MB of raw bitstream). Lossy compression to something worth listening to will usually be around 10x compression, so ~30MB for an original…

If you were using AAC (or anything else that's more advanced than MP3) a 3MB file would actually be listenable for a short song. A 150MB FLAC file would be about 20-30 minutes long (based on a typical bitrate of 700-1000 kilobits per second).

> If you were using AAC (or anything else that's more advanced than MP3) a 3MB file would actually be listenable for a short song.

Even mp3 works for "a short song", that's not the context of my comment though, its context is a 150MB FLAC file (~300MB bitstream) recompressed to 3MB with Opus.

> A 150MB FLAC file would be about 20-30 minutes long

A point I noted in my comment.

Re: It’s Opus, it rocks and now it’s an audio codec standard

#64

Post by nullc »

hetman wrote: post #53
azakai wrote: post #9

Earlier quoted context omitted.

Even if it was tested by the courts, you can appeal. And even after the appeal, you can appeal to a higher court, all the way to the Supreme. And even if was tested there, congress can pass a law that allows it. And even if that happens the Supreme court can strike down the law. And even if that happens, the public can mount a revolution and tear down the legal system. But, practically speaking, Opus has extremely go…

Yeah. The public is going to mount a revolution over a music format. I don't think being contrary for its own sake is helpful here. The whole point of "tested by the courts" is that it's already gone through the appeals process. As in, you have the final decision you're going to get out of the courts.

The courts determine the applicability of single patents, or a single parties patents (e.g. in cases of misconduct). There is no legal process that can prove something non-infringing, unless you expect something to go to court millions of times.

But this doesn't mean that something can't be designed in a way which avoids all known, and much unknown risk, and licensed in a way which makes frivolous attack less likely.

The obsessives here somes forget that when we talk about comparing things what matters is the relative merits. The commercial codes are absolutely and uncertainly encumbered. And the commercial codec providers have generally had a poor track record of creating codecs unencumbered by third party rights (mostly because they don't make an effort to: they erroneously assume the regular royalties will satisfy all comers). Opus doesn't have these issues and even compared to most software an effort was made to avoid infringement, but nothing can escape the impossibility of absolute certainty under the current patent system.

Re: It’s Opus, it rocks and now it’s an audio codec standard

#65

Post by wissler »

ZeroGravitas wrote: post #57
wissler wrote: post #11

Earlier quoted context omitted.

No matter how many times I'm downvoted, it's still not unencumbered. It's simply not in the nature of our patent system that something this complex can be unencumbered, unless it's with respect to an expired patent. I know my position causes a lot of cognitive dissonance with people, because it implies that the system is fundamentally unfair. Well, you can either take the red or the blue pill.

I believe the system is fundamentally unfair, but also think that you are the one that's bought into their propaganda to the point that you're not thinking straight. Particularly as you naively think that an expired patent is enough to protect you from the system.

"Particularly as you naively think that an expired patent is enough to protect you from the system."

Note that I said with respect to...

Re: It’s Opus, it rocks and now it’s an audio codec standard

#66

Post by ZoFreX »

masklinn wrote: post #63
ZoFreX wrote: post #60

Earlier quoted context omitted.

If you were using AAC (or anything else that's more advanced than MP3) a 3MB file would actually be listenable for a short song. A 150MB FLAC file would be about 20-30 minutes long (based on a typical bitrate of 700-1000 kilobits per second).

> If you were using AAC (or anything else that's more advanced than MP3) a 3MB file would actually be listenable for a short song. Even mp3 works for "a short song", that's not the context of my comment though, its context is a 150MB FLAC file (~300MB bitstream) recompressed to 3MB with Opus. > A 150MB FLAC file would be about 20-30 minutes long A point I noted in my comment.

Oops, I misread your comment quite heavily. Apologies for the extremely redundant follow-up!

Re: It’s Opus, it rocks and now it’s an audio codec standard

#67

Post by pslam »

randallu wrote: post #6
nvmc wrote: post #2

MP3 is getting very long in the tooth, not to mention the fact that it's encumbered by patents. A new codec would be nice, but hardware adoption of the codec will take a while. Long enough, dare I say, to kill it dead in the water.

Why would you say that? Most "hardware" decoders are DSPs that run software loaded onto them at runtime. This goes for anything with an OMAP, Tegra or Samsung (Samsung's own decode block) SoC in (that I know for sure) and probably almost everything else. Tegra3 and OMAP4 can decode WebM in hardware, for example.

Almost no hardware audio decoders use DSPs, or at least actually need to, since about a decade or more now.

The manufacturers you mention use DSPs for bad reasons - usually the inertia of software already using a coprocessor and not being willing to license a new codec for the general purpose core. Audio decoding and encoding is an extremely low percentage of available CPU, and it's just not worth off-loading it.

Video is another matter, at least when talking about HD. It's still very much worth using special purpose DSPs for that.

For audio, the existence of hardware DSPs is simply not a barrier to entry.

Re: It’s Opus, it rocks and now it’s an audio codec standard

#68

Post by azakai »

nullc wrote: post #52
azakai wrote: post #30

Earlier quoted context omitted.

> I expect Firefox and Chrome to adopt this within months, Firefox already adopted it (it's in nightly builds). Chrome seems to have WontFixed it, http://code.google.com/p/chromium/issues/detail?id=104241

It's actually in Firefox 15, not just nightly. People on Reddit are saying chrome's position has reversed but I don't have a link. Works in Opera already if you have gstreamer's opus plugin, and they've apparently said they'll ship it.

The chrome bug just changed from WontFix to Available.
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