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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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post Jan 27 2013, 02:26
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@seren
I don't use 32 kb/s for music, but I'm hoping it will happen someday. The original format of the song I uploaded is .MOD and it's only 15KB which gives it a bitrate of 1.2 kb/s and even lower when compressed.

@saratoga
I've explained myself numerous times, I won't do it a third. Also, choosing MP3 for quality isn't a wise choice given its inefficient block sizes and other numerous design flaws make it incapable of transparency at any bitrate.

@db1989
You're just being ignored, for now anyway. I intended to respond but posts concerning the original topic came back up so I went with the flow.

@greynol
I never said anything about archival quality.

@C.R.Helmrich
I increased Opus' delay to the maximum 60ms to produce that sample. Is this close to AAC's? I'm aware it was intended for VoiP but your latest listening test got my attention when I heard AAC has finally been made obsolete, so I was puzzled why this was only true for one bitrate? No I haven't ABX'd higher bitrates but since I do not intend to switch to Opus even if it is only slightly higher quality, I'm not wasting the time. USAC is due which will crush both AAC and Opus.
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C.R.Helmrich
post Jan 27 2013, 13:00
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Good morning,

QUOTE (Warning @ Jan 27 2013, 03:26) *
I increased Opus' delay to the maximum 60ms to produce that sample. Is this close to AAC's?

QUOTE
This I doubt. AAC-He is not really intended to be transparent.

OK, some clarification is necessary here.

HE-AAC has a frame length of 2048 samples in the normal dual-rate mode, and with its 50% window overlap, one frame spans 4096 input samples = 93 ms @ 44.1 kHz. Opus has very little frame overlap, which makes efficiency go down on tonal signals. So even 60-ms windows in Opus wouldn't be enough to get to the efficiency Level of HE-AAC. And IIRC Opus doesn't have 60-ms windows. I think the developers once mentioned here that the CELT block size can never be more than 20 ms, so a 60-ms frame just contains 3 blocks. Yes, if the block size were 40 ms, it would probably sound better.

HE-AAC is in fact intended to be transparent. In downsampled SBR mode, you can move your SBR start frequency up to 16 kHz or more, i.e. into (nearly) inaudible regions. But nobody uses it that way because then it gives no advantage over AAC-LC.

QUOTE ( @ Jan 27 2013, 03:49) *
QUOTE (Warning @ Jan 26 2013, 18:03) *
AAC will have better technical quality, retaining more inaudible, high-frequency parts

Hey Chris,

Are you OK with this? I'm not!

If you define technical quality as e.g. "maintaining efficiency on different input signal characteristics", I'm perfectly OK with this. The rest is mostly a sign of encoder tuning and has nothing to do with the particular formats.

Some last words to Warning: please stop the cursing! What's the point of calling people trolls etc.

And please upload a FLAC of 30 seconds of that MIDI-like item. And upload it in the Upload forum.

Chris

This post has been edited by C.R.Helmrich: Jan 27 2013, 13:10


--------------------
If I don't reply to your reply, it means I agree with you.
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Posts in this topic
- Warning   Why is opus only good at 64/kbs   Jan 26 2013, 10:31
- - db1989   QUOTE (Warning @ Jan 26 2013, 09:31) So I...   Jan 26 2013, 10:51
- - LithosZA   QUOTE Ok you got me convinced that opus sounds bet...   Jan 26 2013, 12:10
- - C.R.Helmrich   QUOTE (Warning @ Jan 26 2013, 11:31) Also...   Jan 26 2013, 12:18
- - IgorC   QUOTE (Warning @ Jan 26 2013, 06:31) Also...   Jan 26 2013, 17:29
- - greynol   I'm guessing he's in violation of TOS #12,...   Jan 26 2013, 17:44
- - Kamedo2   QUOTE (Warning @ Jan 26 2013, 18:31) My h...   Jan 26 2013, 22:24
|- - DonP   QUOTE (Kamedo2 @ Jan 26 2013, 16:24) Howe...   Jan 27 2013, 14:06
- - Warning   Results: CODEABC/HR Version 1.0, 6 May 2004 Testn...   Jan 26 2013, 22:56
|- - saratoga   QUOTE (Warning @ Jan 26 2013, 16:56) WMA ...   Jan 26 2013, 23:10
|- - saratoga   QUOTE (Warning @ Jan 26 2013, 16:56) Resu...   Jan 26 2013, 23:20
||- - Warning   QUOTE Unless I'm misunderstanding something, y...   Jan 27 2013, 00:03
||- - db1989   QUOTE (Warning @ Jan 26 2013, 23:03) Wast...   Jan 27 2013, 00:27
||- - saratoga   QUOTE (Warning @ Jan 26 2013, 18:03) QUOT...   Jan 27 2013, 00:37
|- - db1989   QUOTE (Warning @ Jan 26 2013, 21:56) OGG ...   Jan 26 2013, 23:31
|- - DonP   QUOTE (Warning @ Jan 26 2013, 16:56) I...   Jan 27 2013, 14:37
- - IgorC   Achtung! Das ist sehr gut!   Jan 26 2013, 23:05
- - IgorC   Exactly. As poll 2013 has indicated that only two ...   Jan 26 2013, 23:19
- - greynol   ...and with this discussion the troll count just i...   Jan 26 2013, 23:32
- - Warning   http://www.sendspace.com/file/x4ec7d AAC and opus...   Jan 27 2013, 01:07
|- - Nick.C   QUOTE (Warning @ Jan 27 2013, 00:07) .......   Jan 27 2013, 01:14
||- - Warning   QUOTE (Nick.C @ Jan 27 2013, 01:14) QUOTE...   Jan 27 2013, 01:26
||- - greynol   QUOTE (Warning @ Jan 26 2013, 16:26) I...   Jan 27 2013, 01:50
|- - db1989   QUOTE (Warning @ Jan 27 2013, 00:07) You ...   Jan 27 2013, 01:23
|- - saratoga   QUOTE (Warning @ Jan 26 2013, 19:07) EDIT...   Jan 27 2013, 01:24
||- - Warning   QUOTE (saratoga @ Jan 27 2013, 01:24) I t...   Jan 27 2013, 01:34
||- - saratoga   QUOTE (Warning @ Jan 26 2013, 19:34) QUOT...   Jan 27 2013, 01:44
|||- - NullC   This thread is generally awesome. I mostly _expec...   Mar 2 2013, 01:22
||- - db1989   Whether or not Iím being automatically ignored her...   Jan 27 2013, 01:50
||- - C.R.Helmrich   QUOTE (Warning @ Jan 27 2013, 02:34) The ...   Jan 27 2013, 01:50
||- - saratoga   QUOTE (C.R.Helmrich @ Jan 26 2013, 19:50)...   Jan 27 2013, 02:13
|- - Seren   QUOTE (Warning @ Jan 27 2013, 08:07) AAC ...   Jan 27 2013, 01:33
- - greynol   @Chris: That's not the point. We don't ju...   Jan 27 2013, 02:14
- - Warning   @seren I don't use 32 kb/s for music, but I...   Jan 27 2013, 02:26
|- - saratoga   QUOTE (Warning @ Jan 26 2013, 20:26) @sar...   Jan 27 2013, 02:37
||- - Warning   QUOTE (saratoga @ Jan 27 2013, 02:37) I d...   Jan 27 2013, 03:03
||- - saratoga   QUOTE (Warning @ Jan 26 2013, 21:03) QUOT...   Jan 27 2013, 03:19
|||- - Warning   QUOTE (saratoga @ Jan 27 2013, 03:19) Tha...   Jan 27 2013, 06:23
|||- - IgorC   QUOTE (Warning @ Jan 27 2013, 02:23) So w...   Jan 27 2013, 14:07
||- - greynol   QUOTE (Warning @ Jan 26 2013, 18:03) AAC ...   Jan 27 2013, 03:49
|- - C.R.Helmrich   Good morning, QUOTE (Warning @ Jan 27 2013, ...   Jan 27 2013, 13:00
|- - greynol   QUOTE (C.R.Helmrich @ Jan 27 2013, 04:00)...   Jan 27 2013, 14:57
|- - C.R.Helmrich   QUOTE (greynol @ Jan 27 2013, 14:57) Ok g...   Jan 27 2013, 15:10
- - greynol   TOS 8 and 2. Your posting style (it is painfully ...   Jan 27 2013, 06:52
- - [JAZ]   I was tempted to reply to this thread yesterday bu...   Jan 27 2013, 09:46
- - db1989   It didnít take long for the nose-thumbing tantrum ...   Jan 27 2013, 12:43
- - greynol   You better go back and re-read. My Blade comment w...   Jan 27 2013, 15:17
- - Omicron   My encoded AAC is much worse than yours. And that ...   Feb 21 2013, 17:21
- - Warrior_   I'm posting to announce I've done ABX list...   Mar 1 2013, 22:32
|- - greynol   QUOTE (Warrior_ @ Mar 1 2013, 13:32) Abou...   Mar 2 2013, 02:15
|- - IgorC   QUOTE (Warrior_ @ Mar 1 2013, 18:32) Nero...   Mar 2 2013, 20:39
- - db1989   Sup Warning. Bye Warning. P.S. I hope the terribl...   Mar 1 2013, 23:17
- - IgorC   How can they compare audio files by images which w...   Mar 2 2013, 03:03
- - db1989   Part of me would like to enumerate all the ways in...   Mar 2 2013, 03:10
- - splice   Woo. I could feel the hairs growing on the palms o...   Mar 2 2013, 11:18
|- - Dynamic   QUOTE (splice @ Mar 2 2013, 10:18) I unde...   Mar 4 2013, 20:24
- - splice   Thank you for the explanation. I've noticed si...   Mar 4 2013, 21:06


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