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Wavpack Lossy Quality, As good as OGG, MPC or AAC?
Lev
post Apr 17 2003, 11:59
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I note that a certain pet bird has the signature line
QUOTE
WavPack (352/448 kbps) lossy for HQ lossy encodings and transcoding
LAME 3.90.2 (by Dibrom) --alt-preset extreme -Z --lowpass 21 or --alt-preset insane --lowpass 21 for my mp3s
MP2 384 kbps stereo for the classical music on my portable
MusePack 1.15r --insane --xlevel for archiving on CDs


Is he right in using WavPack, as opposed to MPC?

Something tells me the higher the bitrate, the more he likes it - There isn't an MP2 encoder as well tuned as Lame, and cranking the bitrate up to 384 isnt going to make the encoder more 'tuned'. And MPC insane / MP3 APX are virtually unnecessary overkills too; YMMV.


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bryant
post Apr 26 2003, 00:49
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Guruboolez:

I tried to find that sample but could only find one copy and it was compressed with something I couldn't figure out. Could you upload something for me (or point to where I might find it)?

I see what you are talking about, but it seems like it only occurs after the burst, right? This makes sense because there would be some trailing quantization noise there (which could sound like smearing), but there would not be anything before the burst (which is what I thought pre-echo was). I would still like to hear this sample, though.

HansHeijden:

Actually, Matt and I were in frequent contact during that time and traded ideas often. His lossy version was something that he put together in a couple hours IIRC and was really very simple. His lossless encoder was already dividing the audio into blocks, and so what he did was when he encoded each block he checked the level first and then made a decision as to how many LSBs to strip off all the raw samples before he compressed the whole block losslessly. The bits stripped off would obviously go into the "recovery" file (which I don't think he ever implemented). At around 400 kbps this was often transparent, and because his lossless compressor was so good it was very efficient.

The problem with this is that the quantization noise, while very low, can be jumping up and down 5 times per second in 6 dB steps. As long as it's completely inaudible that's fine, but as soon as it approaches the threshold of audibility you might start hearing those discontinuities and I suspect that they would be pretty obnoxious.

WavPack's lossy mode is implemented much later in the compression process and filters the quantization noise rate of change to prevent any audible jumps. I believe that this allows WavPack's lossy mode to be acceptable at lower bitrates because even when the noise approaches audibility it doesn't make itself too obvious. Matt and I discussed this and he decided that incorporating a similar scheme into Monkey's Audio would involve changing too much (and I think he didn't want to wander into the quagmire of lossy codecs).

There is room for improvement, however. For one thing, the lossy mode is currently strictly CBR. It would be possible to implement some simple psycho-acoustic algorithm to determine the relatve audibility of the quantization noise and adjust the bitrate accordingly (i.e. VBR).

Also, I have thought a little about some intelligent switching for joint stereo. As you point out, true stereo is the default and I did this because I found some samples where joint stereo generated some problems (loud sound in only one channel produces audible noise in the other quiet channel) even though most samples benefit from joint stereo. A simple algorithm could be devised to detect the problem cases and only switch to true stereo then.

JohnV:

To use a common American expression, I will try to avoid letting lossy compression become my Vietnam. smile.gif
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Posts in this topic
- Lev   Wavpack Lossy Quality   Apr 17 2003, 11:59
- - budgie   Lev: Hahaha... you are very, but very witty pet. ...   Apr 17 2003, 12:03
- - Garf   I don't know - what MP2 encoder do you use and...   Apr 17 2003, 12:14
- - Jan S.   First of all a lowpass at 21KHz is insane. Most mo...   Apr 17 2003, 12:30
- - westgroveg   Very original, I don't ever recall some one st...   Apr 17 2003, 12:33
- - Lev   QUOTE The normal lowpass the presets use should be...   Apr 17 2003, 12:38
- - Garf   QUOTE (westgroveg @ Apr 17 2003 - 01:33 PM)Ed...   Apr 17 2003, 12:50
- - Lev   QUOTE It will be interesting to see the results MP...   Apr 17 2003, 13:54
- - budgie   QUOTE (Jan S. @ Apr 17 2003 - 03:30 AM)First ...   Apr 17 2003, 14:22
- - budgie   QUOTE (westgroveg @ Apr 17 2003 - 03:33 AM)It...   Apr 17 2003, 14:34
- - Lev   QUOTE Most modern crappy-shitty CD players maybe c...   Apr 17 2003, 14:57
- - Garf   QUOTE Most modern crappy-shitty CD players maybe c...   Apr 17 2003, 15:02
- - Garf   Specifically: QUOTE Once the quality exceeds what...   Apr 17 2003, 15:10
- - budgie   QUOTE (Lev @ Apr 17 2003 - 05:57 AM)--bah.....   Apr 17 2003, 15:11
- - Lev   QUOTE Stop repeat BS you read here and there on th...   Apr 17 2003, 15:17
- - Garf   QUOTE Dear Lev, it really doesn't matter, if y...   Apr 17 2003, 15:18
- - budgie   Garf: QUOTE Last I looked, MPC at standard level ...   Apr 17 2003, 15:35
- - Garf   QUOTE If you read carefully, I wrote (Not in the s...   Apr 17 2003, 15:47
- - Garf   QUOTE I tested a lot with Vorbis 1.0 at -q4 and th...   Apr 17 2003, 15:51
- - Lev   QUOTE Why was SACD or DVD-A developed? Companies a...   Apr 17 2003, 15:53
- - westgroveg   I may be wrong but doesn't SACD & DVD-A al...   Apr 17 2003, 16:11
- - guruboolez   And better spatial restitution (multichannel)   Apr 17 2003, 16:14
- - Garf   QUOTE I may be wrong but doesn't SACD & DV...   Apr 17 2003, 16:19
- - Ardax   QUOTE (Garf @ Apr 17 2003 - 11:19 AM)QUOTE E...   Apr 17 2003, 16:32
- - Messer   QUOTE (Garf @ Apr 17 2003 - 03:47 PM)But you ...   Apr 17 2003, 17:28
- - bryant   QUOTE (Lev @ Apr 17 2003 - 03:38 AM)Where can...   Apr 17 2003, 18:33
- - john33   QUOTE (Lev @ Apr 17 2003 - 11:38 AM)Where can...   Apr 17 2003, 19:58
- - floyd   Anyone else sick of of sigs with lists of favorite...   Apr 17 2003, 21:46
- - Mac   Back to the original question... how good is Wavpa...   Apr 17 2003, 22:29
- - den   @floyd I know what you are saying, but I find havi...   Apr 18 2003, 05:10
- - den   Me again. I've been doing some further testin...   Apr 18 2003, 08:39
- - JohnV   Thanks for the interesting reports, den.   Apr 18 2003, 09:12
- - rjamorim   I thank you too. I find listening tests with WavPa...   Apr 18 2003, 17:28
- - den   OK, some follow up comments about this rather uniq...   Apr 21 2003, 11:14
- - Peter Harris   QUOTE (den @ Apr 21 2003 - 05:14 AM)1. Origin...   Apr 21 2003, 17:41
- - Moneo   I did a little test to see how wavpack hybride mod...   Apr 21 2003, 18:09
- - rjamorim   I would believe Den used settings where codecs bec...   Apr 21 2003, 18:10
- - sony666   QUOTE (Peter Harris @ Apr 21 2003 - 05:41 PM)...   Apr 21 2003, 18:11
- - rjamorim   @moneo: have you tried doing the inverse with APE+...   Apr 21 2003, 18:15
- - Moneo   QUOTE (rjamorim @ Apr 21 2003 - 06:15 PM)have...   Apr 21 2003, 19:34
- - rjamorim   QUOTE (Moneo @ Apr 21 2003 - 03:34 PM)rjamori...   Apr 21 2003, 22:22
- - den   Just to clarify a few things - Yes, I chose the m...   Apr 21 2003, 22:54
- - den   OK, just snuck in two more test tracks, the same s...   Apr 22 2003, 01:40
- - rjamorim   Great! Truly great. Thanks a lot for your test...   Apr 22 2003, 01:49
- - den   @Moneo Sorry for not respondng earlier. I probabl...   Apr 22 2003, 05:42
- - bryant   QUOTE (den @ Apr 21 2003 - 01:54 PM)Wavpack d...   Apr 22 2003, 05:55
- - hans-jürgen   QUOTE (den @ Apr 22 2003 - 06:42 AM)As far as...   Apr 22 2003, 14:22
- - den   hans-jürgen wrote QUOTE I don't mean to spoil ...   Apr 22 2003, 14:56
- - Mac   I have wanted to test this out myself, but sadly I...   Apr 22 2003, 15:43
- - den   Mac, I can't comment on the Winamp plug-in as...   Apr 22 2003, 16:06
- - rjamorim   QUOTE (den @ Apr 22 2003 - 12:06 PM)Very conv...   Apr 22 2003, 16:15
- - den   @ rjamorim 1. As far as I can tell, you can't...   Apr 23 2003, 02:05
- - rjamorim   QUOTE (den @ Apr 22 2003 - 10:05 PM)2. I foll...   Apr 23 2003, 02:16
- - den   I do know a few things about C programming actuall...   Apr 23 2003, 04:37
- - KikeG   Den, I suggest that if you do further testing, you...   Apr 23 2003, 08:04
- - den   Thanks KikeG. Apart from the tests I've poste...   Apr 23 2003, 08:38
- - Lev   Just Failed to ABX WavPack @ 320 with flying colou...   Apr 23 2003, 21:41
- - den   QUOTE I had absolutely no idea what I was looking ...   Apr 24 2003, 01:51
- - den   I couldn't resist trying wavpack with some of ...   Apr 25 2003, 01:22
- - guruboolez   Tried with castanet2.wav file : 255 kbps (mesure...   Apr 25 2003, 02:56
- - den   Thanks for your post guruboolez. It's good to...   Apr 25 2003, 03:16
- - Delirium   Thanks for the results; they're very interesti...   Apr 25 2003, 04:15
- - budgie   I think it's really good that I could contribu...   Apr 25 2003, 12:39
- - 2Bdecided   This is a very interesting thread. One interesting...   Apr 25 2003, 14:11
- - Garf   Just for the record, shorten has a lossy mode too.   Apr 25 2003, 14:39
- - HansHeijden   Here is that tread again David, with posts about l...   Apr 25 2003, 15:02
- - Garf   QUOTE (den @ Apr 25 2003 - 02:22 AM)I'm t...   Apr 25 2003, 15:29
- - Garf   QUOTE (budgie @ Apr 25 2003 - 01:39 PM), but ...   Apr 25 2003, 15:36
- - 2Bdecided   QUOTE (HansHeijden @ Apr 25 2003 - 02:02 PM)H...   Apr 25 2003, 15:47
- - budgie   QUOTE (Garf @ Apr 25 2003 - 06:36 AM)It's...   Apr 25 2003, 15:53
- - HansHeijden   Hmm, it seems the lossy ape dll (from may 2001, ve...   Apr 25 2003, 19:07
- - JohnV   QUOTE (budgie @ Apr 25 2003 - 02:39 PM)For my...   Apr 25 2003, 19:19
- - bryant   First of all, I'd like to thank everyone who h...   Apr 25 2003, 20:14
- - guruboolez   QUOTE (bryant @ Apr 25 2003 - 08:14 PM)Also, ...   Apr 25 2003, 20:45
- - HansHeijden   Bryant, I made a lossy ape of your sample, and mad...   Apr 25 2003, 20:55
- - JohnV   LOL.. now bryant is dragged to the lossy quality b...   Apr 25 2003, 21:44
- - HansHeijden   Bryant, the -j1 switch you mention indeed gives mu...   Apr 25 2003, 22:47
- - Dibrom   QUOTE (budgie @ Apr 25 2003 - 07:53 AM)QUOTE ...   Apr 26 2003, 00:14
- - bryant   Guruboolez: I tried to find that sample but could...   Apr 26 2003, 00:49
- - guruboolez   Here is the sample, compressed by a simple but imp...   Apr 26 2003, 01:04
- - den   @HansHeijden Thanks for making me aware of the los...   Apr 26 2003, 10:16
- - den   Just did a quick and dirty ABX test of wavpack los...   Apr 26 2003, 10:51
- - bryant   Guruboolez: Thanks for the sample. I didn't r...   Apr 28 2003, 21:19
- - den   Thanks for the info bryant. I concur that the joi...   Apr 29 2003, 01:23


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