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Wavpack Lossy Quality, As good as OGG, MPC or AAC?
bryant
post Apr 17 2003, 18:33
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QUOTE (Lev @ Apr 17 2003 - 03:38 AM)
Where can I get a Wavpack Encoder / Decoder / Plugin?  (Yes, I know, UTFS, sorry)

Normally, WavPack is available at www.wavpack.com but I am currently between hosting providers and (surprise!) it did not go exactly as planned. It should be resolved (no pun intended tongue.gif ) in a few hours.

BTW, for the purpose of evalulating WavPack's lossy quality it is important to use the "high" quality mode (which is not the default). This is an option to the command-line program (-h) and also available in Speek's frontend and Spoon's plugin for dBpowerAMP.
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john33
post Apr 17 2003, 19:58
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QUOTE (Lev @ Apr 17 2003 - 11:38 AM)
Where can I get a Wavpack Encoder / Decoder / Plugin?  (Yes, I know, UTFS, sorry)

At my 'Other Stuff' Mirror 1. smile.gif


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floyd
post Apr 17 2003, 21:46
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Anyone else sick of of sigs with lists of favorite codecs/commandlines etc.?
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Mac
post Apr 17 2003, 22:29
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Back to the original question... how good is Wavpacks lossy quality in comparison to the other codecs used here? I wouldn't stand a chance of ABX'ing myself, it doesn't go as low as 60kbs afaik smile.gif Someone with ears please do tell!


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den
post Apr 18 2003, 05:10
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@floyd
I know what you are saying, but I find having the sigs useful to see what others are trying. If it wasn't for these sigs, I wouldn't have tried Vorbis believe it or not... Also thanks to budgie, I was also enticed to try Wavpack. dry.gif

@everyone else
I think every forum needs a budgie. Otherwise people tend to get into the forum's main groove, and start answering every newbie inquiry with the standard answer. You might not agree with budgie and sometimes budgie posts opinions without backing it up, but the posts make you think outside the square you live in. wink.gif

@mac and others who are interested.
Curiosity killed this cat, so I dug up the latest wavpack and did some WinABX tests. I don't think of myself as having golden ears (I love Minidisc afterall!), but I can often pick out Ogg Vorbis q6, LAME aps and very occasionally fluke ABXing MPC q5 with my normal music, 70-90's rock/pop stuff. I've never tried the problem samples.

I tried the first 10 seconds of Mandela Day - Simple Minds from their Street Fighting Years CD. With LAME aps and Ogg Vorbis 1.0 q6 I can get this virtually everytime. Nothing major, just minor swirliness in some of the piano chords and something in the percussion not being quite as sharp., but it's very close. MPC q5 I'm usually just guessing!

With Wavpack 256 kbit lossy, I hit 15/15. Wavpack 320 kbit lossy, I hit 12/15. Wavpack 352 kbit lossy, I hit 8/15 initially and then got 10/15. The thing is though, I'm not hearing significant problems at any of these rates, the main thing I'm picking up is background hiss. It's slightly more pronounced in the Wavpack version, and it get's louder as you go down in bit rate. blink.gif

I tried 128 kbit without ABXing, and in this small segment, there were no killer artefacts that I could detect without concentrating. In comparison MP3 and Vorbis at these bitrates introduce an obvious wateryness in the piano stabs, and the percussion starts to smear.

What does this all mean? Maybe there is another option out there for archiving your CDs. Go Wavpack hybrid at whatever bitrate you can afford/put up with, keep the .wv file on your harddisk for listening, the odd transcode (in my case record to MD) and keep the .wvc (correction) files on CDRs. Then you have a set of reasonable quality lossy files for everyday use, and the same music in lossless when you need to do a serious transcode, or want the original wav file...

As I said, I don't have golden ears, and would love to read the opinions of some of the other members out there...

I can't easily post my samples for the time being, but perhaps some else can try some of their own music and post their thoughts...

Den

Editted to change second lossy to lossless in third last paragraph (19/4/2003)

This post has been edited by den: Apr 19 2003, 14:03


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den
post Apr 18 2003, 08:39
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Me again.

I've been doing some further testing, and again, I'm ABXing Wavpack lossy@352 consistently, but not from artifacts, just subtle differences in background hiss. Just to make sure I wasn't doing something weird, I tried to ABX Wavpack lossless, and as you would expect, I can't as it is identical. I just wanted to make sure that there wasn't some weird noise being added as I encoded. laugh.gif

Also in my last post, I commented regarding an informal listen at 128kbit being free of obvious artifacts. Ignore that statement, as I'm finding that when I use Speek's front end, I can't seem to compress anything below ~230 kbits. If I put in anything less than ~230, I still get a 230 kbit file with the stuff I'm testing. Everything above that works OK though, and I'm still impressed with the quality. rolleyes.gif

230kbit is still quite good, but the subtle background noise becomes more obvious in quiet passages. Not distracting, but you notice it because it's not normally there with the same passage as a musepack, or high bitrate mp3/vorbis file. I like how Wavpack does not add rubbish to the music as such, it just adds more hiss-like background noise, at least to my ears.

I'm going to dabble with this "codec" a bit more, and perhaps report my opinion later. I think I may have found a cool compromise for me, keeping the lossy files on my PC for everyday transcoding to Minidisc through foobar, and keeping the correction files backed up so I can go truly lossless when I choose. From here I going to rip and encode a bunch of my everyday listening stuff, and see how it goes.

Den.

This post has been edited by den: Apr 18 2003, 08:40


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JohnV
post Apr 18 2003, 09:12
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Thanks for the interesting reports, den. smile.gif


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rjamorim
post Apr 18 2003, 17:28
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I thank you too. I find listening tests with WavPack lossy mode very welcome, since it's an unique form of compression (comparing to the others discussed here), and there's a lack of comprehensive tests about it.

Cheers. smile.gif


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den
post Apr 21 2003, 11:14
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OK, some follow up comments about this rather unique form of audio compression.

My main interest here was to see if Wavpack lossy could provide a better compressed lossy source for further transcoding. Because I use Minidisc with its NetMD capability everything I transfer ends up in ATRAC3. I also have other devices that use other formats, and the Sony software is pretty ordinary for archiving and maintaining a music library, so I have been archiving everything as higher end vorbis, musepack and mp3 and then transcoding these as required into ATRAC. Lossless would be the ultimate for me, but I just don't have that much space for all my cds.

I took a favourite track of mine, Blue Monday - New Order (the original 12") and did the following:
1. Original wav into ATRAC3 via foobar and Sony OpenMG for replaygain.
2. Original wav into Wavpack lossy @ 320 kbits then to replaygain'd wav via foobar, then ATRAC3.
3. Original wav into mpc q6 (v1.15r) then replaygain'd wav via foobar, then ATRAC3.
4. Original wav into ogg q6 (v 1.0) then replaygain'd wav via foobar, then ATRAC3.
5. Original wav into mp3 aps via LAME 3.90.2 then replaygain'd wav via foobar then ATRAC3.
6. Original wav into ogg q3 then replaygain'd wav via foobar, then ATRAC3.
7. Original wav into mp3 128 CBR via LAME 3.90.2 then replaygain'd wav via foobar then ATRAC3.

I then transferred all of the above onto Minidisc and sat through them all, listening to certain sections, but particularly the classic drum machine intro, and snares at the end of the intro section, and the jet flyover in the middle.

I could wax lyrical about all sorts of little artifacts that popped up in different sections, but in summary, every track had some artifacts, thanks to the wonder of ATRAC3 encoding. (ATRAC3@132 kbit is kinda like mp3@128 kbit, the average listener will say, "wow, totally transparent, CD quality!!!", but some practice and intimate knowledge of the original recording will reveal minor artifacts. sad.gif )

What stood out though was the similarity between wavpack lossy and the original wav when listened to as ATRAC3 encodes on MD. They were effectively identical. As mentioned in my previous posts, there was a very slight increase in overall background noise as faint hiss, but it was very quiet, and this is an analogue recording anyway. The other minor ATRAC3 introduced artifacts were identical between wav and wavpack, despite the wavpack being a transcode.

All of the others showed varying degrees of additional artifacts introduced by transcoding. In terms of my preference quality wise, mpc q6 was the next best, followed closely by mp3 aps and vorbis q6. The mpc added some subtle clicks and pops in the drum machine intro, while the last two introduced additional smearing in the drum machine intro and snares. (I'm guessing the mp3 and vorbis are adding some extra pre-echo to ATRAC3's pre-echo.) Then the low bit rate mp3 and vorbis really showed what transcoding can do to your music. THe drum machine beats started to run together, with pre and post echo. I'm sure to many of my friends they would still be very acceptable for everyday listening, but not so good when you have heard better.

It would appear to me now, that my best choice is wavpack lossy @ 320 kbits, (perhaps with the correction files archived somewhere as well) seeing as I regularlly transcode to MD, and sometimes mp3. For others who transcode, there could be something here for you as well.

Den.


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Peter Harris
post Apr 21 2003, 17:41
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QUOTE (den @ Apr 21 2003 - 05:14 AM)
1. Original wav into ATRAC3 via foobar and Sony OpenMG for replaygain.
2. Original wav into Wavpack lossy @ 320 kbits then to replaygain'd wav via foobar, then ATRAC3.
3. Original wav into mpc q6 (v1.15r) then replaygain'd wav via foobar, then ATRAC3.
4. Original wav into ogg q6 (v 1.0) then replaygain'd wav via foobar, then ATRAC3.
5. Original wav into mp3 aps via LAME 3.90.2 then replaygain'd wav via foobar then ATRAC3.
6. Original wav into ogg q3 then replaygain'd wav via foobar, then ATRAC3.
7. Original wav into mp3 128 CBR via LAME 3.90.2 then replaygain'd wav via foobar then ATRAC3.

Apples to oranges. Congratulations on showing that Wavpack lossy @320kbps can beat everyone else at ~200kbps (Except for 6 and 7 which are ~112 and 128kbps, of course).
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Moneo
post Apr 21 2003, 18:09
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I did a little test to see how wavpack hybride mode would perform compared to a quick-n-dirty musepack+monkey's audio combo.

The original .wav file was 54 072 524 bytes in size ("The Sails of Charon" performed by Yngwie Malmsteen).

1. I encoded it to .mpc using mppenc 1.14 with --quality 8 --xlevel.

2. Then, I decoded the mpc file to .wav

3. Using mix-paste with "invert" checked in Cooledit, I subtracted the decoded wav from the original, and then encoded the resulting "difference" file with monkey's audio using "extra-high" compression. Note that for some reason mix-pasting difference file over decoded mpc gave some very rare last-bit errors (72 in total for that file).

I compared the file sizes with wavpack 3.97 hybrid mode using -b352 -c -h as well as the original file compressed with monkey's audio "extra high"..

The results were:

.mpc file size - 10206936 bytes (266 kbit/s)
difference.ape - 30494008 bytes
total mpc+ape size - 40700944 bytes

.wv file size - 13491318 bytes (352 kbit/s, as expected)
.wvc file size - 25959505 bytes
total wv+wvc size - 39450823 bytes.

Original compressed with monkey's audio was 38014984 bytes,
and the total size of original.ape and original.mpc was 48221920 bytes.

Thus, encoding to mpc and then compressing the difference with monkey's audio makes certain sense, as it offers a 15% improvement over keeping both the lossless encoding of the original and the mpc file.

Compared to this "mpc+ape hybride encoding" biggrin.gif, wavpack hybride mode at 352 kbps offers an additional 3% decrease in size, at the expence of a larger lossy file, as well as (according to den) decreased transparency.

This post has been edited by Moneo: Apr 21 2003, 18:14
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rjamorim
post Apr 21 2003, 18:10
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I would believe Den used settings where codecs become transparent, rather than caring about bitrate consistency.


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sony666
post Apr 21 2003, 18:11
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QUOTE (Peter Harris @ Apr 21 2003 - 05:41 PM)
QUOTE (den @ Apr 21 2003 - 05:14 AM)
1. Original wav into ATRAC3 via foobar and Sony OpenMG for replaygain.
2. Original wav into Wavpack lossy @ 320 kbits then to replaygain'd wav via foobar, then ATRAC3.
3. Original wav into mpc q6 (v1.15r) then replaygain'd wav via foobar, then ATRAC3.
4. Original wav into ogg q6 (v 1.0) then replaygain'd wav via foobar, then ATRAC3.
5. Original wav into mp3 aps via LAME 3.90.2 then replaygain'd wav via foobar then ATRAC3.
6. Original wav into ogg q3 then replaygain'd wav via foobar, then ATRAC3.
7. Original wav into mp3 128 CBR via LAME 3.90.2 then replaygain'd wav via foobar then ATRAC3.

Apples to oranges. Congratulations on showing that Wavpack lossy @320kbps can beat everyone else at ~200kbps (Except for 6 and 7 which are ~112 and 128kbps, of course).

hmm agreed... at least I would have been interested how MPC insane/braindead compares to wavpck 320k for the sake of fairness (not that I would use/recommend such high MPC settings, as stated that -q6 is already very close).
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rjamorim
post Apr 21 2003, 18:15
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@moneo: have you tried doing the inverse with APE+MPC to see if the result is really the same as the original wav?

I personally would still prefer using Wavpack hybrid. First because it's easier biggrin.gif, second because I can play back losslessly if the correction file is in the same directory. I can't do that with APE+MPC.


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Moneo
post Apr 21 2003, 19:34
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QUOTE (rjamorim @ Apr 21 2003 - 06:15 PM)
have you tried doing the inverse with APE+MPC to see if the result is really the same as the original wav?

Yes.

There were 72 last significant bit errors. I think that it was because of the difference between two files going over 16 bit treshold at these positions.

I also agree that the whole process is very clumsy. smile.gif

rjamorim
According to den, mpc at --quality 5 sounded transparent to him, and wavpack's lossy encoding at 352 kbps didn't. That's what I mean by "decreased transparency". I didn't perform any listening tests myself.

Edit: using a simple utility that subtracts wavs and gives bit-identical results, diff.ape increases by only 24 bytes, so the results are essentially the same.

This post has been edited by Moneo: Apr 21 2003, 20:00
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rjamorim
post Apr 21 2003, 22:22
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QUOTE (Moneo @ Apr 21 2003 - 03:34 PM)
rjamorim
According to den, mpc at --quality 5 sounded transparent to him, and wavpack's lossy encoding at 352 kbps didn't. That's what I mean by "decreased transparency".  I didn't perform any listening tests myself.

That's true.

BTW: @Den: are you using WavPack lossy at high quality mode? (-h)


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den
post Apr 21 2003, 22:54
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Just to clarify a few things -

Yes, I chose the mpc q6, vorbis q6, lame aps based on what either I have tended to find is transparent, or what others (including myself) have used when transcoding, either to MD, or to mp3s for their friends. laugh.gif On many other threads in this forum, members have mentioned transcoding from mpc q6/ vorbis q6 to mp3 for sharing, car players, portables, etc. Transcoding also seems to be budgies main use for wavpack lossy.

Yes I am using the high quality option in wavpack. Haven't tried it without.

Apples to oranges, I agree. I am going to repeat the test sometime to with more closely matching bitrates. After all mpc, vorbis and mp3 @ 320 kbits could be closer to the wave and wavpack results in terms of less introduced artifacts from transcoding, but I suspect that won't be the case. Wavpack doesn't apply any signficant psychoacoustic modelling AFAIK, it just applies its normal lossless compression, and then starts throwing away "the least significant bits" to get to the specified bitrate. (Would love a clarification of what that means from the developer wink.gif ) The others apply specific models, and will all introduce some artifacts at any bitrate. It's a case of whether they can be heard or not. As has been posted on here many times, if you take a problem sample, even with mpc, and keep upping the bitrate, some artifacts do not go away, they just become less obvious, even at q10. I suspect something similar will happen with mpc in this case, and these will be "amplified" by the transcode to ATRAC3 but I need to test.

Lastly, I included the last two for comparison, and also because I intend to use these results to educate some of my brothers in the MD 'hood. They all like to talk about how 128 kbit from Kazaa rulz, and low bitrate oggs are perfect on their MDs. laugh.gif

After all, if I can get a similar, or better result for my particular needs (transcoding to MD) with a higher bitrate mpc, vorbis or mp3, which is still below 320 kbit, this lossy wavpack option has less appeal, but on the other hand, these others don't offer a lossless mode if I retain the correction file elsewhere. biggrin.gif

I have a heap of other tests I wish to perform, and as I progress, I'll post the results.

Den.


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den
post Apr 22 2003, 01:40
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OK, just snuck in two more test tracks, the same song (Blue Monday - New Order) encoded in mpc@q10 (beyond braindead!) and LAME 3.90.2 MP3@insane. The mp3 was obviously at 320 kbits, and the mpc was just under. (~315 IIRC, I don't have the files here on this PC).

As I suspected, these could be still be distinguished from the wav and wavpack lossy examples when transcoded into ATRAC3@132 kbit and played back on Minidisc. The mpc was still very good, but there were discernible small pops and squeaks between the beats in the drum machine intro. Once things got going in the middle of the song, the rest of it was very close to the wav/wavpack samples.

The LAME track was also signficantly better than the previous mp3 and vorbis tracks, but still slightly behind mpc@q6 tested previously. There were some extra noises and slight smearing in the intro and the highhat and snare sounds, but it was significantly better than the vorbis q6 and LAME aps tracks. When the song gets into the thick of it, the bass guitar "melody" and percussion sections were also not quite as "punchy" as the wav/wavpack/mpc examples. I'm guessing that most of this is due to the double pre-echo on pre-echo from both mp3/vorbis and ATRAC3. When listened in isolation, these effects are hardly noticeable, but they become more obvious listening to the tracks back to back.

I also tried to blind ABX test my tracks. It isn't easy to ABX test with Minidisc, but I got my wife to shuffle tracks around without telling me the selection, and when doing this, I could consistently group the wave/wavpack lossy together, mpc q10/q6/LAME api together, LAME aps/vorbis q6 together and mp3 128kbit/vorbis q3 together, but not readily distingush within each of these groupings, every single time.

This is telling me that Wavpack lossy@320 is probably the best for my minidisc transcoding needs, so it might be time for me to update my signature! laugh.gif

I still want to try some straight comparisons between Wavpack lossy, Vorbis, Musepack and LAME without the transcode to Minidisc at a later date, but would be interested to hear other points of view on Wavpack lossy's usefulness as a lossy codec.

Hope this has been useful.

Den.


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rjamorim
post Apr 22 2003, 01:49
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Great! Truly great. Thanks a lot for your tests, Den. They are definitely very helpful.

QUOTE
This is telling me that Wavpack lossy@320 is probably the best for my minidisc transcoding needs, so it might be time for me to update my signature!


Indeed. smile.gif


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den
post Apr 22 2003, 05:42
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@Moneo

Sorry for not respondng earlier. I probably didn't make myself clear. As far as transparency was concerned, Wavpack lossy at 352 and 320 kbit is effectively transparent to me. It sounds the same in terms of the actual music with no audible artifacts. What I was ABXing every time was a slight increase in background hiss. At these bitrates, the hiss was very slight, but with the volume cranked up, it was there. I've gotta say that to pick it, I had the volume considerably higher than what was actually comfortable for listening to the music itself and the drum machine intro was hurting my ears. laugh.gif Not exactly normal listening conditions.

Your hybrid MPC+Monkey's is an interesting point, and I've heard of others who package Ogg vorbis and FLAC files together. As Rjamorim has said though, the Wavpack is certainly easy to convert backwards and forwards. If you happen to have the .wv file by itself, it is lossy, but if you happen to copy the .wc file across into the same folder, instant lossless instead. Very convenient.

My last tests also showed that even at MPC q10 transcoded to ATRAC3 was not transparent against original wav direct to ATRAC3, but Wavpack @ 320 kbit was if you were not listening for the slight increase in background hiss.

Thanks for your comments, and also others who reminded me of the importance of comparable bit rates.

Den.

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bryant
post Apr 22 2003, 05:55
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QUOTE (den @ Apr 21 2003 - 01:54 PM)
Wavpack doesn't apply any signficant psychoacoustic modelling AFAIK, it just applies its normal lossless compression, and then starts throwing away "the least significant bits" to get to the specified bitrate. (Would love a clarification of what that means from the developer wink.gif )

First of all, Den, thanks a lot for testing out WavPack and taking the time to describe your results. I appreciate it.

The easiest way to describe the way the lossy mode works is to compare it to regular lossless. Anyone who has messed around with lossless audio compression has noticed that the lower the sound level of the track, the better the compression. In fact, just by reducing the level of an audio sample it's possible to get just about any arbitrarily low bitrate. This could be done manually by normalizing a track down to (for example) 10%, then losslessly compressing it, then cranking it back up after decompression. This would work fine, but the problem is that the quantization noise added would be constant throughout the track and so it would probably be audible during the quiet portions and you would still be wasting resolution during the loud parts. The whole problem here is that the ear works logarithmically and PCM is just too, well, linear!

The way WavPack lossy works is to modulate the added noise continuously so that it is [hopefully] always masked by the music to the same degree. This means modulating slowly enough that it doesn't spike during transients (or when the predictor is adjusting) but quickly enough that it doesn't become audible during quiet parts of the music.

If you want a more detailed description of that's going on there's a few paragraphs about it at the beginning of the words4.c module of the source code also.
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hans-jürgen
post Apr 22 2003, 14:22
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QUOTE (den @ Apr 22 2003 - 06:42 AM)
As far as transparency was concerned, Wavpack lossy at 352 and 320 kbit is effectively transparent to me. It sounds the same in terms of the actual music with no audible artifacts. What I was ABXing every time was a slight increase in background hiss. At these bitrates, the hiss was very slight, but with the volume cranked up, it was there.

I don't mean to spoil your party, but background hiss (slight or not) is an artifact. wink.gif


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den
post Apr 22 2003, 14:56
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hans-jürgen wrote
QUOTE
I don't mean to spoil your party, but background hiss (slight or not) is an artifact.


Yep. you're absolutely right. Just to clarify, when I used the word artifact above, I am referring to the audible, additional sounds that are being added and alterations to the actual music itself. These include pops, clicks, smeared attacks, fluttery decays during sustained notes, ringing and others. All of these were detectable to some degree in all of the mpc, vorbis and mp3 transcoded ATRAC files at all tested bit rates. I could not detect any of the above characteristics over those introduced by ATRAC on top of the original wav file when I transcoded from Wavpack lossy @ 320 however.

Instead Wavpack introduced this slight hiss, and yes, it is technically an artifact. I should have expressed this differently. What I meant was that to my ears, it was preferable to have a slight, but barely perceptible increase in background hiss, over the quite distracting additional noises that were being introduced by the other codecs. Some mp3 portables I have listened to in the past added more hiss than Wavpack during playback due to their cheap circuits. My MD at least seems to be based on high quality clean sounding electronics. wink.gif Which makes the hiss a little easier to detect.

Some people might prefer the extra bits and pieces added to the music, others might prefer the hiss. I prefer the hiss.

Thanks for the advice regarding my terminology. smile.gif It's worth getting it right.

Den.


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Mac
post Apr 22 2003, 15:43
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I have wanted to test this out myself, but sadly I managed to lose around half of my files while formatting my computer sad.gif

I hear that the Winamp (or whatever) plugin can automatically detect the correction file and play back lossless files to you if the lossy & correction are in the same directory... how much strain does this add to the decoding process, it's taking 2 streams and adding them together on the fly to my imagination, does this provide a significant increase in decode time/difficulty?

I have to say, I'm interested by the sound of this encoder smile.gif


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den
post Apr 22 2003, 16:06
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Mac,

I can't comment on the Winamp plug-in as I have only tried foobar which plays Wavpack back natively.

On my Duron 700 desktop system though, foobar plays back the lossy, or the lossy + correction file without any difficulty. I haven't checked CPU usage, but it doesn't choke, and you can seek through the files readily, although seeking is not quite as quick to respond as the other lossy formats, like mp3, mpc.

As you say, when foobar only sees the .wv file in the directory, you get lossy. If the .wc file happens to be present as well, you get lossless. Very convenient, and very easy to switch between lossy to lossless by copying or removing the .wc file. B)

I haven't noticed any significant slowdown when using the correction file to get lossless, but I haven't tested it thoroughly.

Den.


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