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wavpack lossy for archive and transcoding, 512kbps
zorba
post Mar 10 2009, 20:02
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hello,

my recent rips have been done with Max : WavPack lossy at 512kbps.

then, I transcode them into ogg vorbis Q3 for portable and/or AAC in itunes.

What I like is fast encoding and fast transcoding while having a good size/quality ratio for both archive and portable use.
Do I need to pay attention to noise, even with those overkilling 512kb bitrates ?

I don't want lossless because it's too big and I'm not keen on blind tests.

thank you.
Z
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botface
post Mar 10 2009, 20:18
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QUOTE (zorba @ Mar 10 2009, 19:02) *
hello,

my recent rips have been done with Max : WavPack lossy at 512kbps.

then, I transcode them into ogg vorbis Q3 for portable and/or AAC in itunes.

What I like is fast encoding and fast transcoding while having a good size/quality ratio for both archive and portable use.
Do I need to pay attention to noise, even with those overkilling 512kb bitrates ?

I don't want lossless because it's too big and I'm not keen on blind tests.

thank you.
Z

If you don't fancy blind tests why not just spot-check a few tracks that you know very well. Preferably ones that will enable you to hear any possible noise problem. I used to use Wavpack Lossy at around 450kbps and never found noise to be a problem especially after Bryant added noise shaping a year or so back. These days I use LossyWav/Flac. Mainly because it is truly VBR so I don't have to worry that a difficult passage might find it running out of bits, which can conceivably happen with Wavpack - though, as I said I've never actually found noise to be a problem.
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shadowking
post Mar 11 2009, 06:27
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512k was flawless even in the earlier days without psy modeling or joint stereo - using the high mode .
In reality, You would be hard pressed to abx anything @ 400k these days with a strong setting like -hx4. I'd go even further and say that you can take things down to 350 k without sacrificing much quality as we now have basic psymodeling as in dynamic noise shaping + auto joint stereo. With the 4.50 encoder I find 270 k gives more or less a similar quality to 180 k traditional encoder. In addition, Guruboolez found that transcoding wavpack 350..400k was very close to perfection.

This post has been edited by shadowking: Mar 11 2009, 06:37


--------------------
Wavpack -b450s0.7
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zorba
post Mar 11 2009, 10:54
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thank you

I don't use dynamic noise shaping neither joint stereo nor -x,-h. Everything is set to auto with cdex (pc at job) and Max (mac at home).


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bryant
post Mar 13 2009, 18:37
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QUOTE (zorba @ Mar 11 2009, 01:54) *
I don't use dynamic noise shaping neither joint stereo nor -x,-h. Everything is set to auto with cdex (pc at job) and Max (mac at home).

Unless you specifically override it with the -s or -j options, you get dynamic noise shaping and joint stereo by default in lossy/hybrid mode in recent WavPack releases (at the CD sampling rate, anyway).

At a bitrate of 512 kbps, I am confident that audible degradation (even for transcoding) will never be an issue. I use 384 kbps for the same purpose, and your bitrate will give over 8 dB less noise than that. Being able to specify something like -x4 would be better in some obscure cases, but the advantage of fast encoding goes away then.
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zorba
post Mar 13 2009, 21:44
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QUOTE (bryant @ Mar 13 2009, 18:37) *
QUOTE (zorba @ Mar 11 2009, 01:54) *
I don't use dynamic noise shaping neither joint stereo nor -x,-h. Everything is set to auto with cdex (pc at job) and Max (mac at home).

Unless you specifically override it with the -s or -j options, you get dynamic noise shaping and joint stereo by default in lossy/hybrid mode in recent WavPack releases (at the CD sampling rate, anyway).

At a bitrate of 512 kbps, I am confident that audible degradation (even for transcoding) will never be an issue. I use 384 kbps for the same purpose, and your bitrate will give over 8 dB less noise than that. Being able to specify something like -x4 would be better in some obscure cases, but the advantage of fast encoding goes away then.


thanks Bryant,

well, I'm trying to transcode some wavpack lossless into wavpack lossy 512.

I wanted to use MAX by sbooth.org to get those lossy files but I experience some trouble with it. How can I be sure that MAX goes right and deals with the lossless hybrid version (WV+WVC) when his fellowpart PLAY (Mac player) seems to fail with lossless : when I look at the bitrate of some albums in TRACK INFO with PLAY : it shows only 400kb. As if MAX was dealing with only WV without carrying for the correction files.

Those WVC files are in the same folder that WV files, then I don't know if MAX can do the job when PLAY seems not to be able to play correction files.



PS: Lossless Wavpack with correction files are dating from my Windows times with EAC.

This post has been edited by zorba: Mar 13 2009, 21:47
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bryant
post Mar 14 2009, 01:32
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QUOTE (zorba @ Mar 13 2009, 12:44) *
Those WVC files are in the same folder that WV files, then I don't know if MAX can do the job when PLAY seems not to be able to play correction files.

This has been a question on a few occasions. It's easy for a program that use the libwavpack library to handle the .wvc files, but sometimes they don't and it's not always obvious. I have a plan to create a special test file that sounds completely different when you use the .wvc file to make it easy to tell, but I haven't yet. sad.gif

With a player, an easy way to tell would be to try to rename or move the wvc file in the middle of a track. If the OS lets you do that, then the file is probably not being used.

For a conversion it might be more difficult to do that. What you could do, however, is do the conversion of a track, then rename or move the wvc file, then do the conversion again (somehow not overwriting your previous file). Then you could compare the two results to see if they were identical. If the target was a WavPack file you could just compare the length in bytes; if the source was different the odds are overwhelming that the converted file would be different length. Obviously if you were converting to an uncompressed wav then you would have to actually compare the bytes.

Good luck! smile.gif

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zorba
post Mar 14 2009, 11:55
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thanks,

I'm going to try to move or rename a wvc file when playing the wv.

Actually, I'm at job now (PC). My files are on mac (home) but I'm not sure OSX behaves like Windows.

Anyway, I'll check tonight.
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zorba
post Mar 16 2009, 09:37
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So, I encoded a few tracks from wavpack to ogg with Max (mac os).

I did it 4 times :
- wvc and wv are in the same folder
- wvc and wv are in the same folder and I rename the wvc during the encoding
- wvc and wv are in the same folder, wvc has a different name
- wvc is deleted before the encoding


Ogg files are exactly the same size in bytes : 3 369 703 bytes

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zorba
post Mar 16 2009, 10:51
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same test with correction files and XLD

there seems to be some differences with ogg and mp3

however, if I try to encode to wav, the target files are exactly the same with
WV + WVC
WV + WVC renamed
WV + WVC deleted

????
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