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Why no Vorbis 2-pass?
Phaedras
post Dec 31 2002, 13:59
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I know this question has been brought up before, most specifically on the Vorbis mailing list, but I still don't quite understand why 2-pass encoding isn't supported by Oggenc. Sure, the savings are minimal, but isn't that what lossy coding is all about? To make every bit count?
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gameplaya15143
post Aug 25 2006, 01:27
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2pass encoding is only usefull to speed up the process of getting the most quality out of a given file size (I say 'speed up' because trial & error is the alternative method).

I have yet to see any circumstance where 2pass audio encoding is more usefull than 1pass vbr rolleyes.gif
Does anybody know of any at all?

For video encoding 2pass is very usefull, since the trial & error method is extremely time consuming.


--------------------
Vorbis-q0-lowpass99
lame3.93.1-q5-V9-k-nspsytune
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fpi
post Aug 25 2006, 08:21
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QUOTE (gameplaya15143 @ Aug 24 2006, 18:27) *
I have yet to see any circumstance where 2pass audio encoding is more usefull than 1pass vbr rolleyes.gif
Does anybody know of any at all?


Rehuff can be used only with a two pass encoding (altought this is not the same two pass of video encoding, this is really a two pass).
More infos on rehuff:
http://lists.xiph.org/pipermail/vorbis-dev...ust/018522.html
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Posts in this topic
- Phaedras   Why no Vorbis 2-pass?   Dec 31 2002, 13:59
- - Benjamin Lebsanft   maybe in the future rehuff could be integrated, ma...   Dec 31 2002, 14:06
- - john33   On a single example, rehuff compresses a 6016Kb fi...   Dec 31 2002, 14:24
- - Benjamin Lebsanft   it would be a nice feature to play with and if its...   Dec 31 2002, 14:28
- - robUx4   In video, double pass is not used for saving space...   Dec 31 2002, 15:12
- - Tripwire   I don't know if this is doable, but a 2nd pass...   Dec 31 2002, 15:56
- - Slo Mo Snail   How do you want to detect artefacts? There's n...   Dec 31 2002, 16:02
- - amp   QUOTE I don't know if this is doable, but a 2n...   Dec 31 2002, 16:41
- - john33   @amp: Your explanation is perfectly understandable...   Dec 31 2002, 18:26
- - tangent   QUOTE (robUx4 @ Dec 31 2002 - 10:12 PM)In vid...   Jan 1 2003, 11:10
|- - PatchWorKs   Up! QUOTE (tangent @ Jan 1 2003, 12...   Aug 18 2006, 17:15
- - Mgz   WMAv9 support 2-pass encoding,too /me   Jan 1 2003, 11:20
- - Mac   Going back to john33, saving 3kbs is exactly what ...   Jan 1 2003, 12:00
- - dev0   Besides from the various problems reported about r...   Jan 1 2003, 12:08
- - john33   For those who are interested, oggenc2.2 is now ava...   Jan 1 2003, 12:37
- - kheops   it's a big improvement, i hope we'll see t...   Jan 1 2003, 13:31
- - sven_Bent   does the ogg vidoe container support the rehuff sa...   Jan 1 2003, 14:02
- - john33   QUOTE (sven_Bent @ Jan 1 2003 - 01:02 PM)does...   Jan 1 2003, 14:19
- - schlauf   OK, now I post it here. I just tried the --rehuff...   Jan 1 2003, 16:32
- - S_O   QUOTE Now, having tried to encode this CD, I have ...   Jan 1 2003, 17:21
- - john33   Hmmm, I can't comment at this time other than ...   Jan 1 2003, 17:25
- - schlauf   Yeah, that GraphEdit-Thingo works indeed. Unfortun...   Jan 1 2003, 18:06
- - john33   BTW, I was just trawling through the vorbis-dev ma...   Jan 2 2003, 23:06
- - rc55   John, It seriously makes me bang my head against ...   Jan 6 2003, 01:32
- - LCtheDJ   Yesterday I downloaded oggenc2.2 and tested it usi...   Jan 30 2003, 17:59
- - john33   QUOTE (LCtheDJ @ Jan 30 2003 - 04:59 PM)Yeste...   Jan 30 2003, 18:17
- - LCtheDJ   I see ICL7, optimised for Pentium 4 links for ogge...   Jan 30 2003, 18:44
- - Bedeox   Great work! Now I can increase quality of my f...   Jan 30 2003, 18:45
- - schlauf   QUOTE (LCtheDJ @ Jan 30 2003 - 06:59 PM)Yeste...   Jan 30 2003, 18:48
- - john33   QUOTE (LCtheDJ @ Jan 30 2003 - 05:44 PM)I see...   Jan 30 2003, 19:14
- - DSPguru   QUOTE (kheops @ Jan 1 2003 - 03:31 PM)it...   Jan 30 2003, 19:18
- - john33   QUOTE (Bedeox @ Jan 30 2003 - 05:45 PM)Great ...   Jan 30 2003, 19:19
- - LCtheDJ   Sorry folks, I must have been spacing out yesterda...   Jan 30 2003, 19:35
- - Bedeox   Even worse results here... foobar2000 consumes 100...   Jan 31 2003, 08:22
- - schlauf   QUOTE (Bedeox @ Jan 31 2003 - 09:22 AM)This d...   Jan 31 2003, 08:47
- - Bedeox   Libvorbis should recover from such error properly....   Jan 31 2003, 09:40
- - kheops   thanks DSPguru, i hope we will see again this 2 pa...   Jan 31 2003, 10:54
- - Garf   QUOTE (Bedeox @ Jan 31 2003 - 09:22 AM)<ed...   Jan 31 2003, 11:17
- - Bedeox   Yes, but are they REALLY incorrect? I'll check...   Jan 31 2003, 11:28
- - john33   Comment from Segher, the author of the rehuff rout...   Jan 31 2003, 11:51
- - Bedeox   Reread my post, I stated what's probably incor...   Jan 31 2003, 11:53
- - Bedeox   Look at this... OGG Rehuffed OGG NOT Rehuffed Thi...   Jan 31 2003, 12:55
- - schlauf   There's one more bug to report with oggenc 2.2...   Jan 31 2003, 18:23
- - Garf   Rehuff does not work with mono files IIRC.   Jan 31 2003, 18:33
- - john33   QUOTE (Garf @ Jan 31 2003 - 05:33 PM)Rehuff d...   Jan 31 2003, 19:24
- - Garf   QUOTE (john33 @ Jan 31 2003 - 08:24 PM)QUOTE ...   Jan 31 2003, 19:37
- - Bedeox   Will somebody post here rehuffed and rehuffed/remu...   Jan 31 2003, 20:01
- - callmeace   I did follow the announcement about Rehuff back in...   Mar 25 2004, 03:11
- - mmortal03   yeah, I'd like to know too   Mar 25 2004, 17:25
- - Thomas   Please add 2-pass Vorbis support!   Jul 21 2004, 09:25
- - gameplaya15143   2pass encoding is only usefull to speed up the pro...   Aug 25 2006, 01:27
|- - fpi   QUOTE (gameplaya15143 @ Aug 24 2006, 18:2...   Aug 25 2006, 08:21
- - HbG   What about listening tests where a specific averag...   Aug 25 2006, 02:00


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