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Why is opus only good at 64/kbs
Warning
post Jan 26 2013, 10:31
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So I was very skeptical about opus when it sounded like a new OGG Vorbis hype where the codec is both free and crappy quality. I didn't think without SBR it would be able to compete with Nero HE-AAC. So I compared at different bitrates and opus always sounded worse. I decided to ABX at different bitrates, opus failed on 32 and 48 but not 64 where the treble was audibly brighter than Nero.

Ok you got me convinced that opus sounds better at 64 kb/s, why does it suck so bad at other bitrates? Also, why didn't you guys include WMA in your listening test along with opus? WMA has proven to be slightly superior quality to HE-AAC at 64 kb/s so maybe opus still has a competitor.

Also, fix your biased testing methodology and keep the bitrates as close as possible to the original! Jesus. My hypothetical codec produces output bitrates of 192 kb/s when my quality setting intends it to be half as less, I demand it to be nominated as capable of transparency at 16 kb/s. rolleyes.gif
Your unscientific results makes me keep clear of your website these days.
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db1989
post Jan 26 2013, 10:51
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QUOTE (Warning @ Jan 26 2013, 09:31) *
So I was very skeptical about opus when it sounded like a new OGG Vorbis hype where the codec is both free and crappy quality.
Yeah, you’re right; the many people who think it’s a great and promising new development in audio compression must be delusional.

And Ogg Vorbis “crappy quality” too? Relative to what? It tends to beat MP3.

QUOTE
I decided to ABX at different bitrates
Cool story. Where are your results? This certainly doesn’t belong in Listening Tests without, well, evidence of listening tests.

QUOTE
opus failed on 32 and 48 but not 64 where the treble was audibly brighter than Nero.
Were you ABXing the two lossy codecs against each other rather than against the lossless source?

QUOTE
Your unscientific results makes me keep clear of your website these days.
Given your attitude during this entire post, I don’t think much of value was lost.

This post has been edited by db1989: Jan 26 2013, 10:57
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LithosZA
post Jan 26 2013, 12:10
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QUOTE
Ok you got me convinced that opus sounds better at 64 kb/s, why does it suck so bad at other bitrates?


At very low bitrates HE-AAC v2 uses Parametric Stereo which Opus does not. At those rates Opus uses intensity stereo.
You could try to test both HE-AAC and Opus with mono recordings.

QUOTE
Also, fix your biased testing methodology and keep the bitrates as close as possible to the original!

What original? Do you mean 64Kbps? You know that all those codecs were tested at variable bitrate, right?

This post has been edited by LithosZA: Jan 26 2013, 12:17
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C.R.Helmrich
post Jan 26 2013, 12:18
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QUOTE (Warning @ Jan 26 2013, 11:31) *
Also, why didn't you guys include WMA in your listening test along with opus? WMA has proven to be slightly superior quality to HE-AAC at 64 kb/s ...

Where exactly was this proven? Please dig it out. I've done a MUSHRA test WMA vs. HE-AAC at 64 kbps once, and WMA was inferior. Which confirms the results of e.g. the IRT tests here (newer, WMA 8) and here (older, WMA 4) and Sebastian's test (WMA 10).

If by "biased testing methodology" you're referring to testing with VBR, then here's some recent discussion of that issue. I also prefer testing in CBR to avoid discussion/criticism on how the codec bitrates were calibrated for the test, but then again the codecs we generally test here are often used (and give slightly better quality) in VBR mode, so there's also some merit in testing them that way. You see, it's not that easy to decide.

I believe you should stay a bit longer here and read up on some more things before you accuse us of using unscientific methods.

Chris

This post has been edited by C.R.Helmrich: Jan 26 2013, 12:28


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IgorC
post Jan 26 2013, 17:29
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QUOTE (Warning @ Jan 26 2013, 06:31) *
Also, fix your biased testing methodology and keep the bitrates as close as possible to the original! Jesus. My hypothetical codec produces output bitrates of 192 kb/s when my quality setting intends it to be half as less ...

You have no clue what you're talking about, now do you?

QUOTE (Warning @ Jan 26 2013, 06:31) *
Your unscientific results makes me keep clear of your website these days.

Dear Mr "8-posts", you're free to go wherever you want. Don't worry, we won't miss you either.

Have a nice day.

This post has been edited by IgorC: Jan 26 2013, 17:30
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greynol
post Jan 26 2013, 17:44
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I'm guessing he's in violation of TOS #12, though I can't prove it at the moment.

Nevertheless, I must agree that these nonsensical and unfounded "contributions" are part of the problem rather than the solution. Our forum is better off without them. Please run along if you can't be constructive, Warning.

This post has been edited by greynol: Jan 26 2013, 18:14


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Kamedo2
post Jan 26 2013, 22:24
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QUOTE (Warning @ Jan 26 2013, 18:31) *
My hypothetical codec produces output bitrates of 192 kb/s when my quality setting intends it to be half as less, I demand it to be nominated as capable of transparency at 16 kb/s. rolleyes.gif

I failed to understand this sentence. My guess is like this:

In the last Opus 64k public test, the codecs and settings were calibrated to provide ~64kbps on a large variety of music, but these tests tend to use harder samples and Vorbis used 73.4kbps for the tested samples, which are typically hard. This means, Vorbis will use about 54.6kbps for easier samples, which is somewhat worrisome and annoys me but not something I'd consider unscientific.

However, if Vorbis allocate only 32kbps for easy samples people typically don't test, words like "abuse" or "cheat" would come up to my mind. This hypothetical hyper-VBR allocates more bits to the hard samples people typically test, and "abusing" easy samples exists in calibration albums but people don't test.

Ideally, average bitrates of test samples should be close to calibration albums by including enough easy samples, but preference for harder samples is unavoidable sometimes. My opinion is that testers calculate calibrate_albums_bitrate*2 - tested_samples_bitrate and make sure it isn't extremely low. When it is, add more easy samples.
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Warning
post Jan 26 2013, 22:56
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Results:

CODE
ABC/HR Version 1.0, 6 May 2004
Testname: grcitrance MP4/OPUS

1R = M:\grcopus32.wav
2L = M:\grc64MP4.wav
3L = M:\grc64MP4cbr.wav
4R = M:\grc32MP4.wav
5L = M:\grcopus48.wav
6R = M:\grcopus64.wav
7R = M:\grc48MP4.wav

---------------------------------------
General Comments:

---------------------------------------
1R File: M:\grcopus32.wav
1R Rating: 2.5
1R Comment: Extremely rough
---------------------------------------
2L File: M:\grc64MP4.wav
2L Rating: 3.6
2L Comment: Kinda duller and the upper freqs are distorted
---------------------------------------
3L File: M:\grc64MP4cbr.wav
3L Rating: 3.6
3L Comment: cant tell apart from sample2, I believe it's slightly better
---------------------------------------
4R File: M:\grc32MP4.wav
4R Rating: 2.4
4R Comment: Somewhat less rough than sample1 but has reduced stereo
---------------------------------------
5L File: M:\grcopus48.wav
5L Rating: 2.9
5L Comment: Less distortion than 1 but more than 2 and 3
---------------------------------------
6R File: M:\grcopus64.wav
6R Rating: 4.1
6R Comment: Noticeably rougher treble than original and slightly dull but otherwise pretty good
---------------------------------------
7R File: M:\grc48MP4.wav
7R Rating: 2.8
7R Comment: It has less distortion in the upper freqs than 5 but sounds duller like the upper freq was cut completely and stereo is reduced
---------------------------------------
ABX Results:
Original vs M:\grcopus32.wav
    9 out of 10, pval = 0.011
Original vs M:\grc64MP4.wav
    10 out of 10, pval < 0.001
Original vs M:\grc64MP4cbr.wav
    10 out of 10, pval < 0.001
Original vs M:\grcopus64.wav
    10 out of 11, pval = 0.006
M:\grc64MP4.wav vs M:\grc64MP4cbr.wav
    3 out of 5, pval = 0.500


OGG sounds worse than Nero AAC, your own listening tests proved it before you started biasing the results.

I'm aware the tests are VBR, they STILL have to match the target bitrate as much as possible for the test to be scientific. All the bitrates in my test are VBR but they also are adjusted to be as close to 32, 48 or 64 kb/s as possible, I'm not gonna allow opus to go all the way up to 80 if the target is 64. Not too hard to comprehend. The truth is in the middle. Stop going to extremes and thinking CBR is your only other option. Do VBR and adjust the quality setting to match the bitrate. Stop thinking in black and white.

And I've been lurking here since 2007, thanks. I just rarely post. You run a tightly-moderated fascist hierarchy and are overrun with trolls and people with serious problems. I'll move to North Korea if I wanna deal with that.

I never use parametric stereo, I add -he to Nero. PS makes everything sound worse.

WMA superiority: http://en.wikipedia.org/wiki/Windows_Media...o#Sound_quality I can't find the PDF at the moment, the link is outdated.

QUOTE
I'm guessing he's in violation of TOS #12, though I can't prove it at the moment.


And the fascistic impulse reveals itself already, didn't take too long I see. I wonder why many don't post here...

This post has been edited by Warning: Jan 26 2013, 22:57
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IgorC
post Jan 26 2013, 23:05
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Achtung! Das ist sehr gut! biggrin.gif
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saratoga
post Jan 26 2013, 23:10
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QUOTE (Warning @ Jan 26 2013, 16:56) *
WMA superiority: http://en.wikipedia.org/wiki/Windows_Media...o#Sound_quality I can't find the PDF at the moment, the link is outdated.


Thats WMA Pro, not WMA. They're different formats. WMA Pro is often compared here, but less often as it is essentially a dead format at this point.
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IgorC
post Jan 26 2013, 23:19
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Exactly. As poll 2013 has indicated that only two persons here use wma. If nobody uses it, nobody will test it. I'm not going to test it just for theory. It is a dead format.

This post has been edited by IgorC: Jan 26 2013, 23:41
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saratoga
post Jan 26 2013, 23:20
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QUOTE (Warning @ Jan 26 2013, 16:56) *
Results:


Unless I'm misunderstanding something, you rated opus as the best quality for each bitrate?

Why do you think its worse then AAC?

QUOTE (Warning @ Jan 26 2013, 16:56) *
I'm aware the tests are VBR, they STILL have to match the target bitrate as much as possible for the test to be scientific. All the bitrates in my test are VBR but they also are adjusted to be as close to 32, 48 or 64 kb/s as possible, I'm not gonna allow opus to go all the way up to 80 if the target is 64. Not too hard to comprehend. The truth is in the middle. Stop going to extremes and thinking CBR is your only other option. Do VBR and adjust the quality setting to match the bitrate. Stop thinking in black and white.


Thats not a very useful methodology IMO for testing VBR codecs. The entire point of VBR is to maximize quality for a given bitrate. Forcing a certain bitrate is fine, but at that point you might as well just use CBR as doing so defeats the purpose of VBR.

QUOTE (Warning @ Jan 26 2013, 16:56) *
And I've been lurking here since 2007, thanks. I just rarely post. You run a tightly-moderated fascist hierarchy and are overrun with trolls and people with serious problems. I'll move to North Korea if I wanna deal with that.


FYI this kind of ranting makes you sound like you're insane.
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db1989
post Jan 26 2013, 23:31
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QUOTE (Warning @ Jan 26 2013, 21:56) *
OGG sounds worse than Nero AAC, your own listening tests proved it before you started biasing the results.

Show us this supposed “biasing”.

If anything, Vorbis has not been tested recently because of its having been overtaken by other formats (as was shown in 2011’s multi-format listening test) and its being in line to be replaced by Opus. Still, it is not particularly bad, as you seem to be trying to portray it. Perhaps you should redirect your little crusade against MP3 instead, since it does considerably worse and yet is significantly more popular. Then your frustrated energies might go somewhere.

QUOTE
And I've been lurking here since 2007, thanks. I just rarely post. You run a tightly-moderated fascist hierarchy and are overrun with trolls and people with serious problems. I'll move to North Korea if I wanna deal with that.

Yeah, you probably should stay away. At least then we’ll have one less of those trolls that you mentioned.

I also note your defaulting to the hoary old epithet fascist, as if it’s anything other than a meaningless crutch for people with a chip on their shoulder who want to try to discredit someone who doesn’t agree with them with the maximal chance of getting approval from easily impressed onlookers.

Thankfully, though, the site does not go to the opposite extreme by being an enforced democracy; otherwise, ideas like yours in this thread would get much more traction than they deserve.

QUOTE
And the fascistic impulse reveals itself already, didn't take too long I see. I wonder why many don't post here...

OK! Bye now!
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greynol
post Jan 26 2013, 23:32
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...and with this discussion the troll count just increased by one. wink.gif

EDIT: I see the obvious irony was not overlooked in the previous post.

Please, how is accusing this forum of being biased and run by fascists be interpreted as anything other than trolling?

This post has been edited by greynol: Jan 26 2013, 23:41


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Warning
post Jan 27 2013, 00:03
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QUOTE
Unless I'm misunderstanding something, you rated opus as the best quality for each bitrate?


Only for 64 kb/s did it sound undeniably better, for the others I reluctantly rated it higher because I preferred the more dynamic stereo that opus retained at the expense of being more distorted. It was a choice of choosing from higher quality mono to lower quality stereo. I have another sample that suffers far harder from this distortion and sounds a lot worse than HE-AAC at the same bitrate and you don't even need to ABX to notice.

QUOTE
Why do you think its worse then AAC?


Because it sounds like garbage.

QUOTE
Thats not a very useful methodology IMO for testing VBR codecs. The entire point of VBR is to maximize quality for a given bitrate.


If your given bitrate is 64, don't let me see anything higher on the results page, or lower for that matter.

QUOTE
Forcing a certain bitrate is fine, but at that point you might as well just use CBR as doing so defeats the purpose of VBR.


Except CBR is a lot worse quality at the same output filesize than VBR. I guess the only reason people abandoned MP3 CBR is because they wanted to see what kinda strange numbers their encoder will pick in VBR? *facepalm*

QUOTE
FYI this kind of ranting makes you sound like you're insane.


Wasting your life on a website run by moderators with micropenis syndrome who run the place like their personal dollhouse sounds far more retarded to me. It's not surprising to see what kind of people it largely ends up with as exemplified by a post in the "what's your favorite format and why" poll by a guy who said he likes ATRAC the most because it feels warmest to him and then getting attacked by a pack of dorks for breaking some rule that forbids subjective opinions without an ABX test.......... in a thread where his subjective, meaningless opinion was outright asked for. Y'all need to chill out and take a pill sometime.
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db1989
post Jan 27 2013, 00:27
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QUOTE (Warning @ Jan 26 2013, 23:03) *
Wasting your life on a website run by moderators with micropenis syndrome who run the place like their personal dollhouse sounds far more retarded to me.
You’re really going all-out to be original, hilarious, and not at all thoughtless with your cosmopolitan array of epithets here, aren’t you? Boring gendered insults and accusations regarding mental health… It’s like I don’t even want to argue back because it just doesn’t seem worth it.

QUOTE
It's not surprising to see what kind of people it largely ends up with as exemplified by a post in the "what's your favorite format and why" poll by a guy who said he likes ATRAC the most because it feels warmest to him and then getting attacked by a pack of dorks for breaking some rule that forbids subjective opinions without an ABX test.......... in a thread where his subjective, meaningless opinion was outright asked for.
Nonsense. The question would have been in reference to objective features such as support in hardware/software, feature-set, licensing, etc. To paint it as anything else is indicative of your having a seriously incorrect mental picture of and/or misrepresenting grudge against this site, which makes it your objections to it ever less tenable in either case.
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saratoga
post Jan 27 2013, 00:37
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QUOTE (Warning @ Jan 26 2013, 18:03) *
QUOTE
Unless I'm misunderstanding something, you rated opus as the best quality for each bitrate?


Only for 64 kb/s did it sound undeniably better, for the others I reluctantly rated it higher because I preferred the more dynamic stereo that opus retained at the expense of being more distorted. It was a choice of choosing from higher quality mono to lower quality stereo.


If you don't think it sounds better, then you shouldn't have rated it higher.

IMO the problem here is that you either did the test wrong, or did the test right and don't agree with yourself. I think you need to figure out what it is you believe before posting such strong statements that may or may not be correct.

QUOTE (Warning @ Jan 26 2013, 18:03) *
If your given bitrate is 64, don't let me see anything higher on the results page, or lower for that matter.


If you're testing CBR, sure. But for VBR that will not give you very meaningful results IMO.

QUOTE (Warning @ Jan 26 2013, 18:03) *
Except CBR is a lot worse quality at the same output filesize than VBR. I guess the only reason people abandoned MP3 CBR is because they wanted to see what kinda strange numbers their encoder will pick in VBR? *facepalm*


Wait, so CBR is worse quality, but you think people shouldn't have abandoned it? Why would you recommend someone use settings that you believe don't work as well?

QUOTE (Warning @ Jan 26 2013, 18:03) *
Wasting your life on a website run by moderators with micropenis syndrome who run the place like their personal dollhouse sounds far more retarded to me. It's not surprising to see what kind of people it largely ends up with as exemplified by a post in the "what's your favorite format and why" poll by a guy who said he likes ATRAC the most because it feels warmest to him and then getting attacked by a pack of dorks for breaking some rule that forbids subjective opinions without an ABX test.......... in a thread where his subjective, meaningless opinion was outright asked for. Y'all need to chill out and take a pill sometime.


I understand that you're angry, but silly rants like this don't help your cause. They just make you seem bigoted and ignorant. You need to calm down and then think carefully about what you want to say.
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Warning
post Jan 27 2013, 01:07
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http://www.sendspace.com/file/x4ec7d

AAC and opus at 32 kb/s VBR but both ended up at the exact same filesize. I'd include original wav but didn't feel like uploading 25MB so it's compressed at -q 0.75 and I think qualifies well enough as the original.

You don't even need to ABX to hear what complete shit opus sounds like with this sample. HE-AAC sounds almost transparent, though I'm sure an ABX would help me notice the flaws.

To the best of my knowledge, opus is not related to USAC which is emerging as the next future standard in audio to succeed AAC which I guess means opus will eventually be trashed by superior quality like OGG was by AAC and I hope it does.

EDIT: saratoga, re-read my post. Given your obvious trolling, you're on ignore.

This post has been edited by Warning: Jan 27 2013, 01:13
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Nick.C
post Jan 27 2013, 01:14
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QUOTE (Warning @ Jan 27 2013, 00:07) *
.... I'd include original wav but didn't feel like uploading 25MB....

Why not compress it with FLAC and upload it?


--------------------
lossyWAV -q X -a 4 --feedback 4| FLAC -8 ~= 320kbps
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db1989
post Jan 27 2013, 01:23
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QUOTE (Warning @ Jan 27 2013, 00:07) *
You don't even need to ABX to hear what complete shit opus sounds like with this sample. HE-AAC sounds almost transparent
Aside from your usual exaggerated language, I agree with both of these points. So? It’s one sample. I’d like to think you’ve compared Opus with other codecs across a very broad range of samples and types of material to arrive at your current, authoritatively marketed conclusion.

And anyway, what is the ultimate purpose of this? ‘I don’t like Opus at these very low bitrates, therefore it should be abolished immediately; if you still don’t believe me, listen to this barrage of insults, and PLEASE PAY ATTENTION TO ME’

Whether you like it or not, many people want and will support a forward-looking open codec. Perhaps you should either ignore it or change your approach to aid its development constructively rather than continuing this apparent vendetta.

Or, if you don’t want to do that, I’m sure there are other sites where you can be consoled by others with a similar grudge; here, you’ll probably just get more frustrated, and something tells me you don’t need any more of that.

No one will refuse constructive feedback. But you have to approach it that way. You can’t just storm in and insult everyone and expect people to consider the finer aspects of what you’re saying. See how much delay that caused?

This post has been edited by db1989: Jan 27 2013, 01:31
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saratoga
post Jan 27 2013, 01:24
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QUOTE (Warning @ Jan 26 2013, 19:07) *
EDIT: saratoga, re-read my post. Given your obvious trolling, you're on ignore.


I think I'm raising fair points here. You can't just rate Opus higher quality in your listening test and decide that its lower quality. The fact that you have suggests that you have either done the test incorrectly, or that you in fact are confused about the relative quality of the samples. Surely you can see that contradictions like this indicate a problem?
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Warning
post Jan 27 2013, 01:26
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QUOTE (Nick.C @ Jan 27 2013, 01:14) *
QUOTE (Warning @ Jan 27 2013, 00:07) *
.... I'd include original wav but didn't feel like uploading 25MB....

Why not compress it with FLAC and upload it?


Because I didn't feel like uploading 12.5MB. smile.gif
I've examined the -q 0.75 MP4 with a spectrograph and it only has a couple holes in the very top 20khz shelf in the noise pouches between the spikes of the percussion, so even if you could hear 20khz it wouldn't have a loud enough intensity to be audible and even if you could still hear it, you're missing a few pouches of noise. Not a big deal.
I'll upload a FLAC if people insist, though.
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Seren
post Jan 27 2013, 01:33
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QUOTE (Warning @ Jan 27 2013, 08:07) *
AAC and opus at 32 kb/s VBR HE-AAC sounds almost transparent

Yikes, I'm glad I don't have those ears...
QUOTE (Warning @ Jan 27 2013, 08:07) *
it's compressed at -q 0.75 and I think qualifies well enough as the original.

Really....?

QUOTE (Warning @ Jan 27 2013, 08:07) *
AAC and opus at 32 kb/s VBR

I feel sorry for anyone that has to resort to 32kb/s for music...
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Warning
post Jan 27 2013, 01:34
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QUOTE (saratoga @ Jan 27 2013, 01:24) *
I think I'm raising fair points here. You can't just rate Opus higher quality in your listening test and decide that its lower quality. The fact that you have suggests that you have either done the test incorrectly, or that you in fact are confused about the relative quality of the samples. Surely you can see that contradictions like this indicate a problem?


In the particular sample I tested, I didn't find opus lower or higher quality in the 32 or 48 bitrates, I just found it different, like the developers sacrificed sample quality to retain stereo dynamics. AAC could do that too. I rated opus samples higher reluctantly because they had better stereo in a song where sample quality wasn't as important as stable stereo.

The question is, how does Opus or any codec only have an advantage at one bitrate? It should be higher quality in all cases.
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saratoga
post Jan 27 2013, 01:44
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QUOTE (Warning @ Jan 26 2013, 19:34) *
QUOTE (saratoga @ Jan 27 2013, 01:24) *
I think I'm raising fair points here. You can't just rate Opus higher quality in your listening test and decide that its lower quality. The fact that you have suggests that you have either done the test incorrectly, or that you in fact are confused about the relative quality of the samples. Surely you can see that contradictions like this indicate a problem?


In the particular sample I tested, I didn't find opus lower or higher quality in the 32 or 48 bitrates, I just found it different, like the developers sacrificed sample quality to retain stereo dynamics. AAC could do that too. I rated opus samples higher reluctantly because they had better stereo in a song where sample quality wasn't as important as stable stereo.


According to your test results, you did find it higher quality at all bitrates, hence its a little strange that you're trying to claim otherwise. If you really think that the Opus sample did worse, then you screwed up the test.

QUOTE (Warning @ Jan 26 2013, 19:34) *
The question is, how does Opus or any codec only have an advantage at one bitrate? It should be higher quality in all cases.


There is no reason to think this. Different codecs work better at different bitrates. For example, at 32kbps I'd strongly prefer AAC-HE to MP3. At 192kbps, I prefer MP3.

Furthermore, for any given sample, two equally good codecs will tend to do better or worse then each other based on chance. Usually if you want to find out how two codecs compare, you pick a number of samples and evaluate all of them and then average the scores.
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