Idiocy alert re: mp3

From Edison cylinders to pre-amps to ProTools: talk about it here.
User avatar
krabapple
Posts: 1615
Joined: Wed Apr 16, 2003 4:19 pm

Idiocy alert re: mp3

Postby krabapple » Fri Dec 31, 2004 5:32 pm

I just had to share:

http://www.quadraphonicquad.com/forums/ ... to=newpost

//

Perceptual encoding is a psychoacoustical con trick.
It is Audio snake oil.
You cannot throw away most of the data and still expect it to be exactly the same as it was before.
This is nonsense.

Interestingly enough, the same con is now being done with pictures and video too.
If perceptual compression is really that good, then why are JPEG/MPEG so artifact riddled - and it is far easier to fool the eye than the ear.

Those who claim that 320Kbps MP3 is CD quality - well, words fail me they really do.

Last word from me on this one, as there is no way the pro MP3 mob will ever admit they got conned, so there is no point even attempting to prove different.

Imagine, if you will...
If MP3 is really that good, why are all the 2" multitrack tapes not all archived as MP3 files instead of on that high maintenance tape, or as 24/96 and even 24/192
digital transfers?
because you cannot throw away the data, that is why! It will not be the same quality.
"I recommend that you delete the Rancid Snakepit" - Grant

User avatar
Rspaight
Posts: 4386
Joined: Wed Apr 30, 2003 10:48 am
Location: The Reality-Based Community
Contact:

Postby Rspaight » Fri Dec 31, 2004 7:13 pm

Hell, if he wants to take lossless pictures with his digital camera and store three images per memory card so he's not bothered with "artifact riddling" on his family snaps, that's fine.

Ryan
RQOTW: "I'll make sure that our future is defined not by the letters ACLU, but by the letters USA." -- Mitt Romney

User avatar
krabapple
Posts: 1615
Joined: Wed Apr 16, 2003 4:19 pm

Postby krabapple » Sat Jan 01, 2005 9:30 pm

At least one brave soul there has now taken me up on my offer to test the audibility of high-quality mp3 compression.
"I recommend that you delete the Rancid Snakepit" - Grant

RDK
Posts: 136
Joined: Wed Apr 16, 2003 5:51 pm

Postby RDK » Sat Jan 01, 2005 11:51 pm

Krab, I envy your ability to withstand the pain of banging your head into the wall as much as you must do. Hilarious thread that!
ray

Dob
Posts: 903
Joined: Sun Aug 01, 2004 2:14 pm
Location: Detroit

Re: Idiocy alert re: mp3

Postby Dob » Sun Jan 02, 2005 9:36 am

Neil Wilkes wrote:You cannot throw away most of the data and still expect it to be exactly the same as it was before...If MP3 is really that good, why are all the 2" multitrack tapes not all archived as MP3 files?

I admit that I don't have much experience with MP3s or with the science behind data compression, but I don't understand why these two statements are being ridiculed. They seem reasonable to me.

Krabapple wrote:At least one brave soul there has now taken me up on my offer to test the audibility of high-quality mp3 compression.

I'd be willing to take you up on it as well. I've only listened critically to a few MP3 files but I think I was able to tell the difference. Obviously, these weren't blind tests.
Dob
-------------------
"Democracy is a pathetic belief in the collective wisdom of individual ignorance" -- HL Mencken

User avatar
Rspaight
Posts: 4386
Joined: Wed Apr 30, 2003 10:48 am
Location: The Reality-Based Community
Contact:

Re: Idiocy alert re: mp3

Postby Rspaight » Sun Jan 02, 2005 10:00 am

Dob wrote:
Neil Wilkes wrote:You cannot throw away most of the data and still expect it to be exactly the same as it was before...If MP3 is really that good, why are all the 2" multitrack tapes not all archived as MP3 files?

I admit that I don't have much experience with MP3s or with the science behind data compression, but I don't understand why these two statements are being ridiculed. They seem reasonable to me.


For me, at least, it's ridiculous because the guy is willfully ignoring the whole point of MP3, which is to create an aurally acceptable version of a digital audio file in a tiny space. It was never intended as an archival medium for keeping reference copies of analog recordings.

I have to wonder if all these MP3-hatin' folks never watch movies made after 1992 in order to avoid those nasty lossy-compressed Dolby Digital, DTS and SDDS formats.

Ryan
RQOTW: "I'll make sure that our future is defined not by the letters ACLU, but by the letters USA." -- Mitt Romney

Dob
Posts: 903
Joined: Sun Aug 01, 2004 2:14 pm
Location: Detroit

Re: Idiocy alert re: mp3

Postby Dob » Sun Jan 02, 2005 11:42 am

Rspaight wrote:...willfully ignoring the whole point of MP3, which is to create an aurally acceptable version of a digital audio file in a tiny space.

Right...but isn't he making the point that there is a difference between "aurally acceptable" and "aurally identical"? It seems to me that the argument hinges on whether or not any compression whatsoever is perceptible, not acceptable.
Dob

-------------------

"Democracy is a pathetic belief in the collective wisdom of individual ignorance" -- HL Mencken

User avatar
Rspaight
Posts: 4386
Joined: Wed Apr 30, 2003 10:48 am
Location: The Reality-Based Community
Contact:

Postby Rspaight » Sun Jan 02, 2005 12:05 pm

Right...but isn't he making the point that there is a difference between "aurally acceptable" and "aurally identical"? It seems to me that the argument hinges on whether or not any compression whatsoever is perceptible, not acceptable.


I read his post as putting forth the proposition that anything lossy-compressed (MP3, AAC, MD, DVD, JPEG, DD, DTS, HDTV, DBS, etc.) isn't worth listening to or looking at, simply due to the fact of its having been lossy-compressed -- then offering as supporting evidence the fact that no one uses MP3 to create reference archives of 2" analog master tapes.

I don't think that anyone is arguing that lossy-compressed files are "exactly" the same as they were before -- that's the whole definition of lossy compression. But that's the straw man Neil is attempting to construct.

Ryan
RQOTW: "I'll make sure that our future is defined not by the letters ACLU, but by the letters USA." -- Mitt Romney

User avatar
lukpac
Top Dog and Sellout
Posts: 4591
Joined: Wed Apr 02, 2003 11:51 pm
Location: Madison, WI
Contact:

Re: Idiocy alert re: mp3

Postby lukpac » Sun Jan 02, 2005 12:51 pm

Dob wrote:Right...but isn't he making the point that there is a difference between "aurally acceptable" and "aurally identical"? It seems to me that the argument hinges on whether or not any compression whatsoever is perceptible, not acceptable.


As Ryan pointed out, I don't think that's the case.

At any rate, it seems perfectly logical to me that good compression can be something that is totally unnoticeable to humans at one iteration, but could become audible if done over and over. Think about changing the volume on something a hair. If that "hair" is small enough, you won't notice it. You may not even notice it after 5 "hairs". But keep going, and there will be a point where you'll notice that the volume is different.

Heck, what an analog tape copy? You might not notice *any* difference one generation down, or even a few. But keep copying over and over, and things *will* sound different.
"I know because it is impossible for a tape to hold the compression levels of these treble boosted MFSL's like Something/Anything. The metal particulate on the tape would shatter and all you'd hear is distortion if even that." - VD

User avatar
krabapple
Posts: 1615
Joined: Wed Apr 16, 2003 4:19 pm

Postby krabapple » Sun Jan 02, 2005 8:21 pm

Dob, the reason Neil's statement is pig-stupid is because he's using terms so loosely that it's just a string a straw men -- even *after* i've explained the criteria that go into mp3 quality. Mp3 is one of hte most highly- and rigoroously tested areas of audio there is.

My position, supported by my own experiences and by testing done by the hydrogenaudio.org folks, is that you can throw away data and have the file be *audibly* identical to the original.

It will of course be quite easily *measurably* different from the original. And the amount of data thrown away will of course be *one* of the determinants of audible difference. Others include the nature of the codec and the source file. Thus there are limits to how much data can be thrown away for a given source file using a given codec, before audible artifacting kicks in. These niceties of argument seem entirely beyond Neil's ability to wrap his brain around.

As to why mp3 isn't an archiving medium, that's because once data is thrown away, it's gone forever...which could conceivably limit downstream manipulation. *Lossless* compression could well become the archiving method of choice, though. (I believe lossy video compression is used for film archiving, though)


I will be happy to make ayou a comparison disc where you can test your own ability to tell original from data compressed copy, by sound alone. Originally I'd made a disc of 19 different tracks, each presenting in A/B/X format, , but it seems perhaps more reasonable (and more statistically valid) for you to pick some tracks you know well, and if I have any of them, have me make a disc of them.
"I recommend that you delete the Rancid Snakepit" - Grant

Dob
Posts: 903
Joined: Sun Aug 01, 2004 2:14 pm
Location: Detroit

Re: Idiocy alert re: mp3

Postby Dob » Sun Jan 02, 2005 8:26 pm

lukpac wrote:At any rate, it seems perfectly logical to me that good compression can be something that is totally unnoticeable to humans at one iteration...Think about changing the volume on something a hair. If that "hair" is small enough, you won't notice it.

I think that would depend on the "starting point." For example, if the starting point for the volume was a "hair" above silence (say 1/2 db), you just might notice a reduction to silence. It would be much harder to perceive a 1/2 db reduction at 100db.

If the sound of 16/44.1 happened to be just barely acceptable, and if the CD-A standards dictating the amount of data needed were perfectly efficient, any compression at all might be audible. But if the sound of 16/44.1 is more than good enough, or if there were data efficiencies to be gained from a different protocol (or both), it stands to reason that a certain amount of compression, or data loss, would not be audible.

The tricky part is figuring out just where that audibility threshold is. Some might say that this threshold is not a point, but an area -- with fluctuating borders that are dependent on many other factors, not least the individual listener.

Something else to ponder...if we accept that there is some amount of inaudible compression available for 16/44.1, doesn't that mean that we automatically have to deny the audible benefits of any sort of oversampling, or larger samples? That may be one reason for the refusal to accept the idea of inaudible compresion.
Dob

-------------------

"Democracy is a pathetic belief in the collective wisdom of individual ignorance" -- HL Mencken

User avatar
krabapple
Posts: 1615
Joined: Wed Apr 16, 2003 4:19 pm

Postby krabapple » Mon Jan 03, 2005 1:14 am

The idea of 'inaudible compression' is only unacceptable to people who know nothing of perceptual masking and its crucial role in codec development. This isn't brand new stuff, nor is it controversial in science. Nor does it follow that successfful data compression renders frequency sampling higher than 44 kHz moot. Moving the sample rate higher during *recording* can have benefits for filter design, and moving to higher bit depths eases digital postprocessing.

Audio *upsampling*, of the type offered on some high-end home digital playback devices, though, has not been proven to be anything more than a crock.
"I recommend that you delete the Rancid Snakepit" - Grant

User avatar
Rspaight
Posts: 4386
Joined: Wed Apr 30, 2003 10:48 am
Location: The Reality-Based Community
Contact:

Postby Rspaight » Mon Jan 03, 2005 9:22 am

Audio *upsampling*, of the type offered on some high-end home digital playback devices, though, has not been proven to be anything more than a crock.


Is this because the audbility benefits of moving beyond 16/44 have not been established?

I know that video upsampling, which many DVD players now offer via a digital connection to a HDTV, does actually work. It's not as good as true HD, but the interpolation algorithms do produce an improvement over straight 480p.

Ryan
RQOTW: "I'll make sure that our future is defined not by the letters ACLU, but by the letters USA." -- Mitt Romney

Dob
Posts: 903
Joined: Sun Aug 01, 2004 2:14 pm
Location: Detroit

Postby Dob » Mon Jan 03, 2005 11:33 am

krabapple wrote:...people who know nothing of perceptual masking and its crucial role in codec development.

Since I have no idea what that means, I guess it's safe to say I know nothing about it!

Moving the sample rate higher during *recording* can have benefits for filter design, and moving to higher bit depths eases digital postprocessing.

In layman's terms, does this mean that SACD can potentially sound better than redbook?
Dob

-------------------

"Democracy is a pathetic belief in the collective wisdom of individual ignorance" -- HL Mencken

Dob
Posts: 903
Joined: Sun Aug 01, 2004 2:14 pm
Location: Detroit

Postby Dob » Mon Jan 03, 2005 11:41 am

Rspaight wrote:I know that video upsampling, which many DVD players now offer via a digital connection to a HDTV, does actually work. It's not as good as true HD, but the interpolation algorithms do produce an improvement over straight 480p.

I've heard of these...have you had a chance to see one in action? I'm way behind on this stuff...it was only two months ago that I finally got a TV (high def) that has component inputs. I was amazed at the improvement of component inputs over the S-video inputs (comparing DVD/component to laserdisc/S-video, which may not be a fair comparison).

My TV has the digital inputs as well, but I'm thinking on holding off on a DVD with digital outs in favor of HD-DVD. But that's probably a long ways off.
Dob

-------------------

"Democracy is a pathetic belief in the collective wisdom of individual ignorance" -- HL Mencken