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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

#11

Post by wissler »

azakai wrote: post #9
wissler wrote: post #8

Earlier quoted context omitted.

There is no such thing as "unencumbered by patents". Unless you have a technology that has already been tested thoroughly in the courts, which is the only way you can really determine whether something would be deemed to violate a patent or not, you simply can't know.

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…

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.

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

#12

Post by wissler »

azakai wrote: post #9
wissler wrote: post #8

Earlier quoted context omitted.

There is no such thing as "unencumbered by patents". Unless you have a technology that has already been tested thoroughly in the courts, which is the only way you can really determine whether something would be deemed to violate a patent or not, you simply can't know.

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…

Related:

http://www.mpegla.com/main/pid/vp8/default.aspx

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

#13

Post by tqs »

AceJohnny2 wrote: post #4

I'm not familiar with Opus. Can someone tell me if it is able to dynamically adapt quality based on available bandwidth? If it loses packets in the stream, do we get a 'skip' in the audio or does the quality go down?

It is absolutely able to dynamically adapt based on bandwidth, and is robust to packet loss. It was designed for that :)

http://www.opus-codec.org/ https://wiki.xiph.org/OpusFAQ

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

#14

Post by wmf »

wissler wrote: post #12
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…

Related: http://www.mpegla.com/main/pid/vp8/default.aspx

No updates for 18 months. Did they find any patents?

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

#15

Post by wmf »

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.

The problem is that they never develop firmware updates so if those DSPs don't support yet another open codec on release day, they never will.

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

#16

Post by wissler »

wmf wrote: post #14
wissler wrote: post #12

Earlier quoted context omitted.

Related: http://www.mpegla.com/main/pid/vp8/default.aspx

No updates for 18 months. Did they find any patents?

The mere threat is enough to keep people from investing much in these "alternatives." E.g., Steve Jobs wrote:

"All video codecs are covered by patents," Jobs wrote from his iPad. "A patent pool is being assembled to go after Theora and other 'open source' codecs now. Unfortunately, just because something is open source, it doesn’t mean or guarantee that it doesn’t infringe on others patents. An open standard is different from being royalty free or open source."

You can bet that if Theora ever got traction and seriously interrupted MPLA's revenue stream, there would be suits. Before that time it'd be pointless for them to sue.

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

#17

Post by jmillikin »

mcantor wrote: post #7

I'm not an audio guy. Can anyone explain like I'm five why this new codec was needed? How does it affect me as a consumer of audio? Who out there was saying "Gosh, I want to do X, but it's really tough because existing codecs force me to choose between high quality and low delay"? What is an example of "X" in that sentence?

X = {voip, videoconferencing}

Say you wanted to write a live audio chat app to talk to your friends. If you'd chosen the Speex codec, then voice would come over fine, but trying to show off your new guitar skills would fail because what they heard would sound horrible.

If you'd chosen the Vorbis codec, then everything would sound great, but there'd be a weird "lag" between participants, as if one of them were on the moon. Also, adding too many listeners would severely strain your internet connection's capacity.

Opus has latencies as good as Speex, and can be high-, medium-, or low-quality depending on bandwidth needs.

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

#19

Post by tveita »

AceJohnny2 wrote: post #4

I'm not familiar with Opus. Can someone tell me if it is able to dynamically adapt quality based on available bandwidth? If it loses packets in the stream, do we get a 'skip' in the audio or does the quality go down?

> Can someone tell me if it is able to dynamically adapt quality based on available bandwidth?

Depends on what you mean. It is a variable bitrate codec, and the encoder can easily adjust the bitrate of the stream. But you would need a way to discover the available bandwidth and communicate it to the encoder - Opus is just a codec, not a container or streaming protocol.

> If it loses packets in the stream, do we get a 'skip' in the audio or does the quality go down?

The standard doesn't mandate a specific way to deal with packet loss, but the reference implementation tries to handle this gracefully. [1]

Some properties of the encoding facilitate this: for instance, packets can optionally include a reduced-bitrate encoding of the previous packet to provide redundancy. [2]

[1] http://tools.ietf.org/html/rfc6716#section-2.1.8

[2] http://tools.ietf.org/html/rfc6716#section-4.4

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

#20

Post by bicknergseng »

mtgx wrote: post #5

I expect Firefox and Chrome to adopt this within months, but IE10 is coming out soon. Does it mean it won't have it? And then we'll have to wait another year or more for IE11 to implement it? Not to mention IE9 and IE8 will probably never get it. I also assume WebM will replace Vorbis with Opus very soon?

While MS might not take full advantage of it, IE 10 will have silent updates. I would hope that would mean they drop the monolithic update strategy.
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