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Firefox Beta 15 supports the new Opus audio format

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Re: Firefox Beta 15 supports the new Opus audio format

#31

Post by polshaw »

makmanalp wrote: post #22

When they say perceptually lossless, by whose perception do they mean? Some definition of the average human?

My somewhat educated take on that is that 'perceptually lossless' refers to quality at which the source cannot be reliably picked from the source/encode in any sort of test that would pass as scientific, possibly outside of a few very rare edge cases (sound samples, not people). This happens at lower bitrates than many people might imagine, IIRC v2 lame (~192kbps) has not been reliably identified, nor vorbis v6 (~160kbps). So their claim of 'perceptually lossless' at 256kbps is neither surprising or impressive. (it may be competitive/better at those high bitrates and they are just being conservative with the claims).

Re: Firefox Beta 15 supports the new Opus audio format

#32

Post by SiVal »

notatoad wrote: post #20
slowpoke wrote: post #6

Earlier quoted context omitted.

Unfortunately, according to Wikipedia, Skype holds software patents on parts of the algorithm. Even though they said they'd make them avaiable royalty-free, this still means it isn't completely free.

in some ways, a perpetual unrestricted license is better than an unpatented algorithm. The big excuse for not adopting webm was "uncertainty" about the patent situation. If skype has the patents and is giving free licenses, there isn't any uncertainty here, you know that microsoft has no basis to ever sue.

This is true and is one reason that free things these days are given "licenses" instead of simply being declared by their makers to be in the public domain. The public domain isn't what it used to be.

Re: Firefox Beta 15 supports the new Opus audio format

#33

Post by makmanalp »

polshaw wrote: post #31
makmanalp wrote: post #22

When they say perceptually lossless, by whose perception do they mean? Some definition of the average human?

My somewhat educated take on that is that 'perceptually lossless' refers to quality at which the source cannot be reliably picked from the source/encode in any sort of test that would pass as scientific, possibly outside of a few very rare edge cases (sound samples, not people). This happens at lower bitrates than many people might imagine, IIRC v2 lame (~192kbps) has not been reliably identified, nor vorbis v6 (~160…

So if I'm getting this correctly, a computer test (not a person) has to look at two clips of audio and tell which is the source and which is encoded?

I'm surprised that 192k is actually indistinguishable. I thought some humans could tell the difference there.

Re: Firefox Beta 15 supports the new Opus audio format

#34

Post by SiVal »

Where is Google in all this? They must surely be aware of all such IETF projects. I can understand why Apple wasn't mentioned (Apple Island is a world unto itself to the maximum extent possible), but Google has usually pursued the opposite strategy. This seems like the sort of thing they would get behind unless there is some issue I'm unaware of, and it seems as though Mozilla would mention Google in this infomercial if they were backing it.

Re: Firefox Beta 15 supports the new Opus audio format

#35

Post by Cyranix »

polshaw wrote: post #31
makmanalp wrote: post #22

When they say perceptually lossless, by whose perception do they mean? Some definition of the average human?

My somewhat educated take on that is that 'perceptually lossless' refers to quality at which the source cannot be reliably picked from the source/encode in any sort of test that would pass as scientific, possibly outside of a few very rare edge cases (sound samples, not people). This happens at lower bitrates than many people might imagine, IIRC v2 lame (~192kbps) has not been reliably identified, nor vorbis v6 (~160…

Not a scientific test by any means, but for a quick and dirty take on the matter, here's the Great MP3 Bitrate Experiment courtesy of Coding Horror: http://www.codinghorror.com/blog/2012/06/concluding-the-grea...

Re: Firefox Beta 15 supports the new Opus audio format

#36

Post by taligent »

SiVal wrote: post #34

Where is Google in all this? They must surely be aware of all such IETF projects. I can understand why Apple wasn't mentioned (Apple Island is a world unto itself to the maximum extent possible), but Google has usually pursued the opposite strategy. This seems like the sort of thing they would get behind unless there is some issue I'm unaware of, and it seems as though Mozilla would mention Google in this infomercial…

Exactly that Apple Island with their industry standard H.264 and AAC files.

And Google with their proprietary WebM.

Re: Firefox Beta 15 supports the new Opus audio format

#37

Post by taligent »

ajasmin wrote: post #13
wmf wrote: post #5

Earlier quoted context omitted.

Doesn't Apple's lame excuse of unknown patents apply to all technologies?

Potentially yes. But Microsoft and Apple not supporting VP8 & WebM probably has more to do with these companies being part of MPEG LA (a firm which sell licenses for H.264 related patents).

It has nothing to do with that.

And everything to do with VP8/WebM being a proprietary, non standard at the time that the world consolidated on H.264. That and the fact that H.264 had hardware support when the iPods and Zunes were taking off.

Re: Firefox Beta 15 supports the new Opus audio format

#38

Post by wmf »

SiVal wrote: post #34

Where is Google in all this? They must surely be aware of all such IETF projects. I can understand why Apple wasn't mentioned (Apple Island is a world unto itself to the maximum extent possible), but Google has usually pursued the opposite strategy. This seems like the sort of thing they would get behind unless there is some issue I'm unaware of, and it seems as though Mozilla would mention Google in this infomercial…

Google has a big NIH conflict of interest since they bought GIPS. "On the audio side, we will initially support iSAC, iLBC, G.711, and DTMF, with iSAC being the default. It is a royalty free wideband codec optimized for speech, open sourced at webrtc.org." http://blog.chromium.org/2012/04/chromes-webrtc-roadmap.html It looks like somebody volunteered to add Opus to Chrome and was met with silence: https://groups.google.com/forum/?fromgroups#!topic/discuss-w...

Mozilla says "Audio codecs planned: G.711 & Opus. (Although royalty/license-free, we have no plans to support iLBC, iSAC and G.722)", so as it stands Firefox and Chrome could only interop with G.711 (aka uncompressed). https://wiki.mozilla.org/Platform/Features/WebRTC

Re: Firefox Beta 15 supports the new Opus audio format

#39

Post by taligent »

wmf wrote: post #12
supercow wrote: post #11

Earlier quoted context omitted.

Microsoft actually helped with the development of Opus according to the article. :)

I remember when MS participated in MPEG-4 development and then fought MPEG-4 for years.

And now getting sued by Google over FRAND patents defined in the H.264 standard.
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