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is Ogg Vorbis the best Lossy encoder? (what is?)
snadge
post Jun 8 2011, 04:01
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ive been trying to find out which encoder produces the best audio quality at similar bitrates (say 128k) to other lossy encoders - ive seen a couple of reviews and tests and they seem to point to Ogg Vorbis as being the better encoder - I encoded a WAV file to MP3, AAC, WMA & Vorbis all at 128k CBR and while it was hard to tell any difference the Ogg Vorbis was pumping out higher frequencies at 20Khz + and the rest were up to 18Khz (according to spectrum on Foobar2000)

the only gripe is during conversion Ogg Vorbis was the only one that didnt have the Tag info from the WAV file.

can anyone lead me to more listening test results and the likes so i can ascertain for myself? - i would like others views on "best lossy codec" etc

I read on Wikipedia that AAC at 128k is supposedly Transparent to the lossless source according to listening tests by M-PEG for ITU or something? - I was hoping to adopt AAC as my default rip codec as I have an iPod and MP3 player that plays AAC - but Iam in the market for a new media-player so all this is irrelevant as I can buy something to suite.

thanks in advance for replies smile.gif

please be gentle...im a noob at all this,

This post has been edited by snadge: Jun 8 2011, 04:17


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Xanikseo
post Jun 10 2011, 01:00
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QUOTE (pdq @ Jun 9 2011, 14:25) *
QUOTE (snadge @ Jun 9 2011, 08:56) *
have I got it wrong? sorry...noob... Dynamics I thought meant the audible range from low notes to the highest note you can hear? and VBR on quiet sections of music may be cutting out some higher frequencies that may be playing during that section giving it less 'range' where-as CBR would have that constant higher ceiling making the higher notes more audible?? - correct me if im wrong..im still learning


Yes, VBR uses less bits where less are needed, but where less are needed the encoded audio tends to be more true to the original, not less.

So true. When I see an album/song with a lower bitrate than the target bitrate, I am surer that it is being encoded well - that is, truer to the original. When the bitrate increases, it is a sign that vorbis is less able to encode as accurately, and therefore has to compensate by increasing the bitrate.

I think of VBR as a trick, to make a codec look better than it actually is. VBR means that all the moments in the music that the encoder can't encode well (due to the deficiencies of the design of the codec) can go to ridiculous bitrates to hide the deficiencies of the encoder. But to make up for all the space that has been wasted due to said deficiencies, it cuts back on the bitrate when the encoder comes to a part of the music that the codec can easily handle (where the codec was well designed/thought of). In the end, you have no idea that the codec was struggling to encode part of your file accurately because it all evens out, and you end up getting your target bitrate. Of course if the VBR algorithm itself isn't well designed, then the bitrate will not increase enough at the points where it is needed, and vice versa, and the deficiencies of the encoder are more noticeable. However vorbis has a very good VBR algorithm that has been tweaked a lot over the years by the likes of Aoyumi.

...So back to the point, you should be happy with parts of the file that go below the target bitrate, rather than unhappy.
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db1989
post Jun 10 2011, 01:30
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QUOTE (Xanikseo @ Jun 10 2011, 01:00) *
QUOTE (pdq @ Jun 9 2011, 14:25) *
Yes, VBR uses less bits where less are needed, but where less are needed the encoded audio tends to be more true to the original, not less.
So true. When I see an album/song with a lower bitrate than the target bitrate, I am surer that it is being encoded well - that is, truer to the original. When the bitrate increases, it is a sign that vorbis is less able to encode as accurately, and therefore has to compensate by increasing the bitrate.
Quality setting being equal, from the encoder having to allocate more bits to encode a particular source file, it does not follow that the resulting lossy file is any farther removed from its source than is a file of a lower bitrate from its source. It simply means the encoder judged it required more bits to attain the same (approximate) quality. That’s the entire point of settings based on quality rather than bitrate, after all!

QUOTE
I think of VBR as a trick, to make a codec look better than it actually is.
Way off track, though there’s little point going into great depth (as if I even could!) when there’s bound to be plenty of documentation on VBR explaining its actual rationale. But in short: The best lossy encoder in the world would still benefit from a VBR model because all passages of audio are not created equal. It has nothing (necessarily) to do with inherent incompetence of either the encoder or its format as a whole.

QUOTE
But to make up for all the space that has been wasted due to said deficiencies, it cuts back on the bitrate when the encoder comes to a part of the music that the codec can easily handle (where the codec was well designed/thought of). In the end, you have no idea that the codec was struggling to encode part of your file accurately because it all evens out, and you end up getting your target bitrate.
Sounds like ABR to me, your aforementioned misconception notwithstanding.

QUOTE
Of course if the VBR algorithm itself isn't well designed, then the bitrate will not increase enough at the points where it is needed, and vice versa, and the deficiencies of the encoder are more noticeable. However vorbis has a very good VBR algorithm that has been tweaked a lot over the years by the likes of Aoyumi.
As have the VBR algorithms of all the leading audio codecs. Again, it has nothing to do with intrinsic deficiencies of lossy audio encoding. VBR just is logical given the heterogenous nature of most source material. It makes sense that end-users would prefer oscillating bitrate to disruptive changes in quality.

This post has been edited by dv1989: Jun 10 2011, 01:48
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Posts in this topic
- snadge   is Ogg Vorbis the best Lossy encoder? (what is?)   Jun 8 2011, 04:01
- - SonicBooom!   I hope I'll not get bashed for I am not truly ...   Jun 8 2011, 04:36
- - snadge   thanks for the info im glad you told me about re...   Jun 8 2011, 04:58
- - terhardp   I'm saying this from my personal view, not bas...   Jun 8 2011, 07:10
|- - snadge   QUOTE (terhardp @ Jun 8 2011, 07:10) I...   Jun 8 2011, 17:32
|- - saratoga   QUOTE (snadge @ Jun 8 2011, 12:32) I play...   Jun 8 2011, 18:52
|- - snadge   QUOTE (saratoga @ Jun 8 2011, 17:52) QUOT...   Jun 9 2011, 14:03
|- - DonP   QUOTE (snadge @ Jun 9 2011, 08:03) [ he i...   Jun 9 2011, 15:26
- - googlebot   What is the best car?   Jun 8 2011, 07:43
|- - Lorem Ipsum   The Batmobile.   Jun 8 2011, 08:07
|- - Cron   QUOTE (googlebot @ Jun 8 2011, 08:43) Wha...   Jun 8 2011, 08:10
- - smok3   if planing to rockbox, i would check battery eatin...   Jun 8 2011, 19:15
- - C.R.Helmrich   @ snadge: regarding quality, have a look at http:/...   Jun 8 2011, 19:45
- - Xanikseo   Regarding that link, it's only really useful f...   Jun 8 2011, 22:03
|- - Canar   QUOTE (Xanikseo @ Jun 8 2011, 14:03) Howe...   Jun 8 2011, 22:56
- - snadge   thanks for all the great replies... so, do you th...   Jun 9 2011, 13:43
- - lvqcl   Dynamics? What is it?   Jun 9 2011, 13:49
|- - snadge   QUOTE (lvqcl @ Jun 9 2011, 12:49) Dynamic...   Jun 9 2011, 13:56
|- - pdq   QUOTE (snadge @ Jun 9 2011, 08:56) QUOTE ...   Jun 9 2011, 14:25
- - Xanikseo   QUOTE (pdq @ Jun 9 2011, 14:25) QUOTE (sn...   Jun 10 2011, 01:00
|- - dv1989   QUOTE (Xanikseo @ Jun 10 2011, 01:00) QUO...   Jun 10 2011, 01:30
- - smok3   QUOTE (DonP @ Jun 9 2011, 16:26) QUOTE (s...   Jun 10 2011, 07:10
|- - DonP   QUOTE (smok3 @ Jun 10 2011, 01:10) QUOTE ...   Jun 10 2011, 12:44
|- - saratoga   QUOTE (smok3 @ Jun 10 2011, 02:10) QUOTE ...   Jun 10 2011, 15:32
- - smok3   saratoga, andless is working with my old musepack ...   Jun 12 2011, 11:02
- - Xanikseo   QUOTE (dv1989 @ Jun 10 2011, 01:30) Quali...   Jun 12 2011, 14:07
|- - saratoga   QUOTE (Xanikseo @ Jun 12 2011, 09:07) Whe...   Jun 12 2011, 18:10
- - dv1989   While your post is considered and doesn’t look par...   Jun 12 2011, 17:16
- - Xanikseo   I do accept that vbr is necessary, music does cons...   Jun 12 2011, 20:08
|- - saratoga   QUOTE (Xanikseo @ Jun 12 2011, 15:08) Whe...   Jun 12 2011, 21:09
- - Xanikseo   I meant what kind of signal would represent a prob...   Jun 13 2011, 00:09
- - [JAZ]   @Xanikseo: While everything is representable by se...   Jun 13 2011, 09:46
|- - saratoga   QUOTE ([JAZ] @ Jun 13 2011, 04:46...   Jun 13 2011, 17:14
- - Xanikseo   I never said that you should use a square waves as...   Jun 15 2011, 23:20
- - K-Meleon   @OP: This test shows that 96 kbps QuickTime AAC is...   Jun 16 2011, 07:25
- - B7k   QUOTE (K-Meleon @ Jun 16 2011, 02:25...   Jun 27 2011, 06:47


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