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Once more: Time for a new lossless codec comparision?, More comprehensive, more detail
ktf
post Apr 27 2012, 13:30
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Hi all,

The recent activity on the FLAC-dev mailing list (it's alive again!) has reminded me of something I announced some time ago here but didn't really finish: make a new comparison of lossless codec performance, because most tests are pretty outdated or not very comprehensive. While there isn't much development at the moment (which I pity) especially TAK has developed and I hope FLAC maintenance development will soon turn to improvement. wink.gif As I still have all code of last time I made a comparison (I got it cleaned up and running in about 2 hours) the hardest thing to get right is the selection of music. That's why I set up this thread.

Test structure
I will make several comparisons, as last time it became clear that codecs perform very different when given different material. This asks for several tests for different genres. Moreover, the overall test has to be balanced too. While my taste in music is quite diverse, I hope you can help me cover the voids. I've set up some categories, Heavy (mostly metal), Rock, Electronic, Pop, Jazz, World Music, Orchestral, (Classical) Chamber music, Single-instrument/voice and pre-mix material. The starred items will be included in the main test, I'll try to take 5 out of every 'main' genre. Every item (that is, every album) is equally weighted in the final comparison.

Your opinion is important! smile.gif
So, first of all, which 'main' genres are missing and which categories would you like to be included in the test? If you suggest a genre of category, please recommend me some CD's to buy which more or less 'span' the whole genre. Second, do you think these lists 'span' the whole genre depicted? Please keep in mind it is of course impossible to include every sub-genre, max 5 per genre would be nice.

Heavy
*Mercenary - 11 Dreams
*Dream Theater - Octavarium
Nightwish - Oceanborn
Linkin Park - Meteora
*System of a Down - Mezmerize
*Apocalyptica - Inquisition Symphony
*Metallica - Death Magnetic
Slipknot - All Hope is Gone
Blind Guardian - A Twist in the Myth

Rock (a.k.a less heavy)
*Paramore - Brand new Eyes
*Red Hot Chili Peppers - Stadium Arcadium
*Foo Fighters - Wasting Light
*Nickelback - Black Horse (Onder heavy?)
*Guns and Roses - Chinese Democracy
30 seconds to Mars - This is War
Muse - H.A.A.R.P. (live from Wembley)

Electronic
*Daft Punk - TRON Legacy R3CONF1GUR3D
*Daft Punk - Discovery (which is quite a different subgenre compared to previous entry)
*Tisto - In Search of Sunrise 7: Asia
*The Prodigy - Invaders must Die (?)
*NIN - The Slip (Is dat Electronic?)

Pop
*5CD's of various popsongs
*Duffy - Endlessly
*Coldplay - Viva la vida or death and all his friends
*Katie Melua - The Katie Melua Collection
*Avril Lavigne - Let Go
BLF - Umoja

Jazz, Soul
*The Rosenberg Trio - Djangologists (sample: http://www.youtube.com/watch?v=uOC-xZOWFnc)
*John Coltrane - Kind of Coltrane (Live at the half note '63, Vol 1 + 2)
*Joss Stone - Mind, Body and Soul
(I need some more here)

World music/Folk (very hard to define indeed cool.gif )
*Various - World Music Instruments, Single Reed Instruments (Clarinet)
*Fanfare Ciocarlia - Baro Biao (gypsy brass band)
(please suggest additions)

Orchestral
*Verdi Requiem
*Carneval des Animeaux
Le Sacre du printemps / Petrouchka
*Bach, Magnificat + Mahler, Symfonie nr. 1
Holst - The Planets
*The Lord of the Rings - Two Towers (complete recordings)

Chamber Music
*2 CD's worth of chamber music
*Some unaccompanied chamber choir recording

Single instrument
*EBU Sound Quality Assessment Material (SQAM) CD
Some of my chamber music recordings (hints for myself: kamermuziekexamen + KaMu-blend)
Excerpts from Yann Tiersens Good Bye Lenin and Amelie Poulain
*Ehren Starks - Lines Build Walls

Not categorized (only to balance the overall test)
*BLF - April (to add some slow, balad-like music)
*Halo: Reach soundtrack

*Some pre-mix, 24-bit material (chamber-music, orchestral music, jazz)

Finally, please don't get upset about the choices I made making this list, just tell what you think is wrong. My musical taste is mainly in classical, rock and metal, so I tried to do the others as well as I could. Music and it's divions into genres is subject of much debate, but that's not the point of this list.

Thanks in advance!


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Haubi
post Apr 29 2012, 15:56
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Great idea! It's really time to make a new comparison to see the power of TAK against other lossless codecs and maybe to push the evaluation of FLAC and others!

I think, if we get more than 5 CDs per category, it shouldn't be bad for the test because the more stuff the merrier the comparison!
My opinion so far:

Heavy
-- Apocalyptica (very special kind of metal, that doesn't fit in this category)
+ Pantera - A Vulgar Display of Power (well known)
+ Nightwish (very famous)
+ Children of Bodom - Hate Crew Deathroll

Rock
+ Nirvana - Nevermind (rock reference)

Elektronic
+ The Prodigy - Invaders Must Die (One of them is a MUST)
+ The Prodigy - The Fat Of The Land (One of them is a MUST)
+ Skrillex - Scary Monsters & Nice Sprites


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ktf
post Apr 29 2012, 18:34
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QUOTE (Haubi @ Apr 29 2012, 16:56) *
I think, if we get more than 5 CDs per category, it shouldn't be bad for the test because the more stuff the merrier the comparison!

Problem is the run-length of this test. 40CD's (5 CDs of 8 genres) would have a run-length of ~ 40 hours and some of these codecs run at only 2 to 3 times realtime (it was ~ 1.4x on my older laptop, it will probably be about 2.5x with my new one) so running such a test would then take several days... of course, this can be split up in several runs, but if this test grows to, say, 100 albums, this test might take over a week. rolleyes.gif

QUOTE
Heavy
-- Apocalyptica (very special kind of metal, that doesn't fit in this category)

Right, I'll put that one under the not categorized 'balancing' group.

Thanks for the additions. I'll take them into consideration.

This post has been edited by ktf: Apr 29 2012, 18:37


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Porcus
post Apr 29 2012, 20:16
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Noise? Like Merzbow? Hardly much compressible ... I can report some figures when I get home to my collection.

In the opposite direction: Bobby "Don't Worry, Be Happy" McFerrin has a live album called The Voice, which consists only of his voice a cappella. An interesting one.


(Myself I have enough music to do a comparison off my own collection. What stops me, is that I am missing a test suite which can to the job automatically and reliably ... (the Good Thing to use, I guess, would be some Linux live distribution running from RAM, and which does not try to go online for updates and download them ...) -- plus the fact that I don't really think people care that much anymore.)


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kornchild2002
post Apr 29 2012, 21:50
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In terms of electronic music, I would look at throwing a dubstep band/artist in there like the previously suggest Skrillex. I think Nero should be thrown in there with the album Welcome Reality. To me, it spans various electronic sub-genres and kind of has them all covered. As for NIN, I don't know if I would consider them electronic. They have released some electronic sounding albums (Ghosts comes to mind) but they also have some industrial and metal elements. I would also take Meteora out of the heavy category since it is more hard rock. There are other entries featuring chug-chug-chug riffs. Otep had a new album that came out a few months ago. Marilyn Manson even has an album coming out which is supposed to be more of a return to his older style.

Lastly, I wouldn't put Death Magnetic on there and instead focus on a more traditional metal album such as Megadeth - Thirteen or Anthrax - Worship Music. My main argument against Death Magnetic is that it is mastered pretty poorly and I don't think it is a good representation of what you would find in the genre. Had Metallica not blown it out of proportion, I would keep it on there but I think a different album should be used that better represents the genre.

You may even want to think about throwing some country on there. My experience with the genre is that it is very similar to pop but you may want to get all of your bases covered.
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saratoga
post Apr 29 2012, 22:07
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QUOTE (Porcus @ Apr 29 2012, 15:16) *
(Myself I have enough music to do a comparison off my own collection. What stops me, is that I am missing a test suite which can to the job automatically and reliably ... (the Good Thing to use, I guess, would be some Linux live distribution running from RAM, and which does not try to go online for updates and download them ...) -- plus the fact that I don't really think people care that much anymore.)


Or just a perl/python/whatever script that depended on having the codecs installed on the command line. Then you could install an interpreter and test stuff from Windows too.

We used to have something like that for rockbox test files, where you'd just download one flac and a script would convert it into a half dozen different formats for testing.
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Porcus
post Apr 30 2012, 21:35
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QUOTE (kornchild2002 @ Apr 29 2012, 22:50) *
Lastly, I wouldn't put Death Magnetic on there and instead focus on a more traditional metal album such as Megadeth - Thirteen or Anthrax - Worship Music. My main argument against Death Magnetic is that it is mastered pretty poorly


It might be interesting to see how the formats/encoders do fare on these brickwalled recordings. Suggestion: make a selection of those and label them separately as 'prisoners of loudness war' as if that were a searate genre. (Eat that, Lars Ulrich.)


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Porcus
post Apr 30 2012, 21:47
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QUOTE (saratoga @ Apr 29 2012, 23:07) *
Or just a perl/python/whatever script that depended on having the codecs installed on the command line. Then you could install an interpreter and test stuff from Windows too.


Sure, for size. For reliable results when it comes to speed, you depend on your OS not starting any CPU- or hard drive-intensive processes in the meantime.


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IgorC
post Apr 30 2012, 23:02
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ktf,

it might worth to look for the most used lossless codecs here 2012 ripping/encoding poll

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GeSomeone
post May 1 2012, 16:47
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Apocalyptica is orchestral, isn't it?
If you want to cover the more traditional "Electronic" you should consider (any) Kraftwerk, Klaus Schulze or (not any) Vangelis.
As for Jazz, maybe a "classic" like Miles Davis - Kind of Blue.
If you want to add traditional Country, any album from Alison Krauss+Union Station would do.
For chamber music how about Vivaldi's the four seasons (performance of your choice).

I'm not trying to come up with rare albums, rather the more common ones. It adds up quickly and, if necessary, you could bring it down again to a fewer, most specific for the genre selection.
You have already 2 live albums on the list, those might have as an added characteristic crowd noise/applause. That's OK, I would only suggest, not too many of those.

This post has been edited by GeSomeone: May 1 2012, 17:06
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icstm
post May 1 2012, 17:28
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sorry to sound silly, but what are we hoping to find?
Surely we are only talking about ~5-10% compression differences?
So are we doing compression vs CPU usage? or vs Time taken (as a proxy?)
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derty2
post May 1 2012, 17:36
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IMHO, no test should be without the king of instruments --the church organ-- and here is a benchmark example that will raise the hairs on the back of your neck:

Helmut Walcha, playing "Bach - Toccata and Fugue in D minor BWV 565", on the the Organ of St. Laurens Church, Alkmaar, Holland (1956)

and it is one of the tracks on this CD at ArkivMusic.com
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kwanbis
post May 1 2012, 18:31
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To make it more representative, I would add some salsa, mambo, and reggaeton.


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ktf
post May 1 2012, 18:43
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QUOTE (Porcus @ Apr 29 2012, 21:16) *
Noise? Like Merzbow?


I'm not into that genre at all... but AFAIK it's not really popular. I might be a nice testcase for encoders but this test is not really about that kind of extremes smile.gif

QUOTE
In the opposite direction: Bobby "Don't Worry, Be Happy" McFerrin has a live album called The Voice, which consists only of his voice a cappella.

Thanks for the suggestion.


QUOTE
(Myself I have enough music to do a comparison off my own collection. What stops me, is that I am missing a test suite which can to the job automatically and reliably ... (the Good Thing to use, I guess, would be some Linux live distribution running from RAM, and which does not try to go online for updates and download them ...) -- plus the fact that I don't really think people care that much anymore.)


I run all tests from RAM, and I wrote the test in PHP. It depends on some linux-specific tools like time and du for measuring used CPU time and disk usage. I'll run all tests on an idle PC from a ramdisk (which is not easy to set up in Windows too)

QUOTE (kornchild2002 @ Apr 29 2012, 22:50) *
In terms of electronic music, I would look at throwing a dubstep band/artist in there like the previously suggest Skrillex. I think Nero should be thrown in there with the album Welcome Reality. To me, it spans various electronic sub-genres and kind of has them all covered. As for NIN, I don't know if I would consider them electronic. They have released some electronic sounding albums (Ghosts comes to mind) but they also have some industrial and metal elements. I would also take Meteora out of the heavy category since it is more hard rock. There are other entries featuring chug-chug-chug riffs. Otep had a new album that came out a few months ago. Marilyn Manson even has an album coming out which is supposed to be more of a return to his older style.

I'll put NIN under heavy (labeled as industrial) and remove Meteora. I'll consider your suggested additions

QUOTE
Lastly, I wouldn't put Death Magnetic on there and instead focus on a more traditional metal album such as Megadeth - Thirteen or Anthrax - Worship Music. My main argument against Death Magnetic is that it is mastered pretty poorly and I don't think it is a good representation of what you would find in the genre. Had Metallica not blown it out of proportion, I would keep it on there but I think a different album should be used that better represents the genre.

I was hoping my collections would suffice for most categories, and I don't have any 'trash metal' besides that. However, I'll take a look wink.gif

QUOTE
You may even want to think about throwing some country on there. My experience with the genre is that it is very similar to pop but you may want to get all of your bases covered.

As I live in The Netherlands, I'm not familiar with country. As far as I know it, it should be put under world music/folk, but again, I really don't know anything about country.

QUOTE (Porcus @ Apr 30 2012, 22:35) *
[...]
It might be interesting to see how the formats/encoders do fare on these brickwalled recordings. Suggestion: make a selection of those and label them separately as 'prisoners of loudness war' as if that were a searate genre. (Eat that, Lars Ulrich.)


That would probably be interesting test case indeed.


QUOTE (Porcus @ Apr 30 2012, 22:47) *
[...]
Sure, for size. For reliable results when it comes to speed, you depend on your OS not starting any CPU- or hard drive-intensive processes in the meantime.


With 'time' I can measure CPU and 'real' time elapsed. In the test, I fetch both and check whether they match to 'verify' my results. smile.gif

QUOTE (IgorC @ May 1 2012, 00:02) *
it might worth to look for the most used lossless codecs here 2012 ripping/encoding poll


Thanks. I'll put a litte more focus on ALAC this time I guess smile.gif

Woops, I see there's a limit to the number of quote blocks I can include in my post... strange?

This post has been edited by ktf: May 1 2012, 18:57


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Porcus
post May 1 2012, 18:43
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QUOTE (icstm @ May 1 2012, 18:28) *
sorry to sound silly, but what are we hoping to find?
Surely we are only talking about ~5-10% compression differences?
So are we doing compression vs CPU usage? or vs Time taken (as a proxy?)


I don't think this is a silly question at all. I am not even sure if there is much need for this test at all, but if it is, then I think your suggestion is probably the best comparison to make, along with ranking by size (as if speed were no objective).

For example, in addition to comparing size, what about the following: make a regression line time vs size, and for each codec report -- relative to the regression line -- the compression gain (positive or negative) or the time gain; The latter is probably a better suggestion, as we have two time variables (encoding and decoding) -- then one could report that codec X encodes 1% slower but decodes 5% faster than average?

This post has been edited by Porcus: May 1 2012, 18:49


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ktf
post May 1 2012, 18:50
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I'll continue tongue.gif

QUOTE (GeSomeone @ May 1 2012, 17:47) *
Apocalyptica is orchestral, isn't it?


No. If it should be categorized, it is 'heavy' or 'chamber music'. They're only with four, that doesn't make an orchestra cool.gif

QUOTE
If you want to cover the more traditional "Electronic" you should consider (any) Kraftwerk, Klaus Schulze or (not any) Vangelis.
As for Jazz, maybe a "classic" like Miles Davis - Kind of Blue.
If you want to add traditional Country, any album from Alison Krauss+Union Station would do.
For chamber music how about Vivaldi's the four seasons (performance of your choice).


Thanks for the additions.

QUOTE
I'm not trying to come up with rare albums, rather the more common ones.

Which makes it easy for me to get hold of it. Thanks!

QUOTE
You have already 2 live albums on the list, those might have as an added characteristic crowd noise/applause. That's OK, I would only suggest, not too many of those.


Actually, most orchestral items are live as well, but there you won't hear much 'live noises'. Besides that, it is very relevant for the other genres. I'll keep it in mind, thanks.

QUOTE (icstm @ May 1 2012, 18:28) *
sorry to sound silly, but what are we hoping to find?
Surely we are only talking about ~5-10% compression differences?
So are we doing compression vs CPU usage? or vs Time taken (as a proxy?)


When comparing between encoders (all encoding the same stuff) there is little interesting to see. This test will update the results, as the last comprehensive test I could find has been some years ago, so this will update these results.

However, last time I found that between genres, encoders can perform different. Wavpack for example, did worse on single-instrument music compared to the other encoders. Probably this will show up with other source material as well. This will point out area's of improvement for certain codecs.

As said earlier, most people won't care much anymore. My motivation was the recent 'awakening' of the FLAC-mailinglist smile.gif

QUOTE (derty2 @ May 1 2012, 18:36) *
IMHO, no test should be without the king of instruments --the church organ-- ...

Oh, right, I forgot to add one. I'll use organ spectacular by Jean Guillou, which is IMO very nicely recorded.

QUOTE (kwanbis @ May 1 2012, 19:31) *
To make it more representative, I would add some salsa, mambo, and reggaeton.

Can you suggest some albums?


QUOTE (Porcus @ May 1 2012, 19:43) *
QUOTE (icstm @ May 1 2012, 18:28) *
sorry to sound silly, but what are we hoping to find?
Surely we are only talking about ~5-10% compression differences?
So are we doing compression vs CPU usage? or vs Time taken (as a proxy?)


I don't think this is a silly question at all. I am not even sure if there is any need for this. And if it is, then I think your suggestion is probably the best comparison, along with ranking by size (speed no objective).

Speed no objective? I really won't compress my files to the heaviest Optimfrog compression. While such a list would state it as top-ranked (3 percentpoint better than FLAC -8) decoding ate 50% CPU on my previous computer. Even in seeking you would notice a lag. Speed still is an objective.

There is no need. I just want to make a fair comparison with all styles equally balanced. Current test seem to lack that.

QUOTE
For example, in addition to comparing size, what about the following: make a regression line time vs size, and for each codec report the compression gain relative to the regression line, or the time gain. (The latter is probably a better suggestion, as we have two time variables (encoding and decoding) -- then one could report that codec X encodes 1% slower but decodes 5% faster than average?)

That's an option, but the problem is choosing that line. Tastes differ (there seem to be people actually using the OFR-setting I mentioned above) and I guess the usual graph will supply more information.

This post has been edited by ktf: May 1 2012, 18:53


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Porcus
post May 1 2012, 19:02
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QUOTE (ktf @ May 1 2012, 19:50) *
Speed no objective? I really won't compress my files to the heaviest Optimfrog compression
[...]


I didn't say I wanted anyone to subscribe to the 'speed no objective' point of view, but I still think that there should be a ranking by compression alone (ranked as if speed were no objective).


QUOTE (ktf @ May 1 2012, 19:50) *
That's an option, but the problem is choosing that line. Tastes differ (there seem to be people actually using the OFR-setting I mentioned above) and I guess the usual graph will supply more information.

Regression, as computed from all the encoders?


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ktf
post May 1 2012, 20:35
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QUOTE (Porcus @ May 1 2012, 20:02) *
Regression, as computed from all the encoders?

I guess I don't understand what you mean by regression... unsure.gif

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db1989
post May 1 2012, 21:09
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http://en.wikipedia.org/wiki/Linear_regression

QUOTE (ktf @ May 1 2012, 19:50) *
[] the problem is choosing that line.

In statistics, linear regression is an approach to modeling the relationship between a scalar dependent variable y and one or more explanatory variables denoted X.
In statistics, simple linear regression is the least squares estimator of a linear regression model with a single explanatory variable. In other words, simple linear regression fits a straight line through the set of n points in such a way that makes the sum of squared residuals of the model (that is, vertical distances between the points of the data set and the fitted line) as small as possible.
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ktf
post May 1 2012, 22:06
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QUOTE (db1989 @ May 1 2012, 22:09) *


Thanks, I was thinking of the word regression as they use it in software engineering. tongue.gif

I wonder whether linear regression would be the method to choose. If you would sacrifice going from 200x realtime to 101x realtime for 1 %-point, would you sacrifice going from 100x to 1x for the same 1%-point extra gain? If I would draw this same straight line through this half-logarithmic graph, how is it called?

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Porcus
post May 2 2012, 00:13
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QUOTE (ktf @ May 1 2012, 23:06) *
regression as they use it in software engineering. tongue.gif


In the very least it wasn't http://newagevillage.com/wiki/index.php/Past_Life_Regression .


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kwanbis
post May 2 2012, 04:35
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QUOTE (ktf @ May 1 2012, 17:50) *
Can you suggest some albums?

Let me see what I can do.


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TBeck
post May 2 2012, 22:13
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For quite some time i wanted to write kind of a manual for audio compression tests but never had enough time to do it properly...

Therefore only some quick remarks.

Common properties important for efficiency differences in arbitrary order:

1) Does a file contain relative silent parts?
This for instance reveals weaknesses of the final residual coding stage.
Typical files: Classic, Singer-Songwriter, LossyWav
2) Fast alterations of the signal characteristics?
Reveals, how fast a codec adapts to changes.
Typical files: Electronic, Percussion
3) Predominant tonal instrument or vocal?
Benefits extremely from a good and long predictor.
Typical files: speech, solos in classic, singer-songwriter, some jazz, (extremely) harpsichord
4) A special but not so rare case: Is a file lowpassed, maybe with a lower-bitrate-mp3-like spectrum?
Some codecs don't provide sufficent accuracy for the predictors in this case.

Well, i do care for all these factors, because i want to tune Tak for every aspect. But obviously their importance depends on the individual taste and music selection.

How to create a representative test collection?

If i only knew...

But i know about some pitfalls:

Mastering is a very important factor, especially since the begin of the loudness war. If you only use highly dynamically compressed sources, you really don't have to care much about the specific details listed above!

Because mastering of newly released music has become so important, i usually don't add whole cds to my test collection, but choose 3 songs, either randomly or by properties. Better more cds with possibly different masterings.

Some codecs apply very special techniques, which can result in quite extreme compression improvements, but only for relatively few cds. But if you happen to have overly many in your test set, this will severily reduce the represenetativity of your test. Another point for a many-cds-few-songs-approach.

The newest version of Optimfrog for instance can detect increases of the volume performed during the mastering process, determine the amplification factor, reverse the amplification and code a much lower signal. This can sometimes result in more than 10 percent better compression! I know about it, because i have investigated a similar approach for TAK. I found most opportunities in older masterings (1980-1990) of classic music released by one german label.

Sorry, not enough time to go into more detail...

Hope it helps a bit

Thomas



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saratoga
post May 3 2012, 00:04
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Is there some collection of losslessly encoded, public domain music that would be suitable for testing? Having the tracks freely available would certainly make duplicating and updating the test easier.
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TBeck
post May 7 2012, 20:20
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My primary test set consists of all the files which still seem to be available at rarewares.org: 30-seconds-samples

I can't say they are representative for some special musical taste, but i found that they are affecting nearly any compression-relevant codec properties i could identify.

It would be very nice, if you could include this (quite small) set into your tests.

This post has been edited by TBeck: May 7 2012, 20:23
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