On Fri, 16 Jan 2004 17:47:37 +0000 (UTC)
(Stewart Pinkerton) wrote:

so you were saying that regardless of the encoding compressed files are
always different from the original.

Which is ********.

******** yoursel - whay the frell do you think it's called *lossy*
compression? *Of course* MP3 files are always different from the
original. Sheesh, whatta maroon!

You'll notice I didnt mention mp3 there at all, by the way...

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with ketchup.

On Fri, 16 Jan 2004 13:47:41 -0000, "Stimpy"
wrote:

Kurt Hamster wrote:

There are no gains with MP3 other than price and size.

Portability and convenience? The iPod and iTunes has changed the way I
listen to music. Might not be the same quality as my traditional system
but, fcuk it, if I can have a box the size of a fag packet holding 10,000
songs that I can listen to in the car or almost 30,000 songs (mainly at
320kbps) on my home MP3 jukebox then I'm willing to forego some quality for
the sheer convenience.

WTF? How far away from work *are* you, when you need 10,000 songs in
your iPod? Why not use just a couple of dozen or so at full .wav
quality?
--

Stewart Pinkerton | Music is Art - Audio is Engineering

On Fri, 16 Jan 2004 08:33:52 +0000, Ian Molton wrote:

On Fri, 16 Jan 2004 00:35:04 +0000
Kurt Hamster wrote:

******** to the encoding, the fact remains there are audible
differences between compressed files (at any bit rate) and
uncompressed audio.

Thats ******** because theres more than a couple of non-lossy compressed
formats out there... Also, bear in mind that an encoding doesnt have to
*compress* data at all, although usually encoded data is easier to
compress afterwards.

Look again. I said differences between compressed and non compressed. I
didn't say anything about encoding, non-lossy or otherwise.

the *compression* isnt what affects the quality though. the data is discarded in
the encoding part of the process. The actual compression in mp3 is non-lossy, as it happens.

Bull****. The compression algorithm is *extremely* lossy. What you are
talking about is the *decompression* process.

If you say so. Im not sure I want to argue about perceptual encoding with you though.

Perceptual encoding is a kludge however you look at it. It certainly
isn't an accurate representation of the source.

Fair enough. it might not be technically accurate. However if its sonically accurate
(ie. one cant hear the difference) then I dont care.

While true, this seems a poor excuse in a home system, where mass
storage of digital media is not a problem in 2004. Especially given
your whining about 'maximum accuracy'. Are you not familiar with the
expression 'garbage in, garbage out'?

Because you wanted linearity in the chain with regard to accuracy. Is
the source no longer part of the chain in your neck of the woods?

The content of the source has f*ck all to do with linearity.

That is about the dumbest thing you've said yet - which is an
achievement in itself!
--

Stewart Pinkerton | Music is Art - Audio is Engineering

On Fri, 16 Jan 2004 19:11:53 +0000 (UTC)
(Stewart Pinkerton) wrote:

the *compression* isnt what affects the quality though. the data is
discarded in the encoding part of the process. The actual compression
in mp3 is non-lossy, as it happens.

Bull****. The compression algorithm is *extremely* lossy. What you are
talking about is the *decompression* process.

No, Im talking about the encoding process. IIRC the compression used is
huffman or LZW (or some such). This is done AFTER the encoding process.

The content of the source has f*ck all to do with linearity.

That is about the dumbest thing you've said yet - which is an
achievement in itself!

Linearity is a property of the system, not the data you put into it.

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with
ketchup.

On Fri, 16 Jan 2004 18:30:46 +0000, Ian Molton wrote:

On Fri, 16 Jan 2004 17:47:37 +0000 (UTC)
(Stewart Pinkerton) wrote:

so you were saying that regardless of the encoding compressed files are
always different from the original.

Which is ********.

******** yoursel - why the frell do you think it's called *lossy*
compression? *Of course* MP3 files are always different from the
original. Sheesh, whatta maroon!

You'll notice I didnt mention mp3 there at all, by the way...

Indeed so, but we already know that you use MP3. Or were you going to
weasel out by claiming that you'd been talking about lossless
compression all along? Which would be a lie................
--

Stewart Pinkerton | Music is Art - Audio is Engineering

Hi,

In message , Ian Molton
writes
On Fri, 16 Jan 2004 19:11:53 +0000 (UTC)
(Stewart Pinkerton) wrote:

the *compression* isnt what affects the quality though. the data is
discarded in the encoding part of the process. The actual compression
in mp3 is non-lossy, as it happens.

Bull****. The compression algorithm is *extremely* lossy. What you are
talking about is the *decompression* process.

No, Im talking about the encoding process. IIRC the compression used is
huffman or LZW (or some such). This is done AFTER the encoding process.

It's been a long time, but if I recall, the process goes something like:

Decompose the signal into frames.
Analyse to determine the spectral energy distribution and break signal
into sub-bands.
Allocate bits to each sub-band according to the data rate set in codec.
Compare frequency distribution to psychoacoustic models stored in the
codec, and discard data that would not be perceived due to masking etc.
(This bit is lossy).
Huffman code the bitstream, compressing redundancies in the sample.
(Not lossy - it assigns 'symbols' to bit sequences to achieve
compression without loss).
Finally, format the bitstream.

I'm stretching my memory here, so I could be incorrect on the order of
things, and the above is way oversimplified. If anyone can be bothered,
the real story is at http://www.mpeg.org/MPEG/audio.html

--
Regards,
Glenn Booth

On Fri, 16 Jan 2004 19:23:44 +0000 (UTC)
(Stewart Pinkerton) wrote:


Indeed so, but we already know that you use MP3.

Among other things...

Or were you going to
weasel out by claiming that you'd been talking about lossless
compression all along?

No.

Which would be a lie................

Indeed it would. If I was claiming that.

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with ketchup.

On Fri, 16 Jan 2004 19:15:50 +0000, Ian Molton wrote:

On Fri, 16 Jan 2004 19:11:53 +0000 (UTC)
(Stewart Pinkerton) wrote:

the *compression* isnt what affects the quality though. the data is
discarded in the encoding part of the process. The actual compression
in mp3 is non-lossy, as it happens.

Bull****. The compression algorithm is *extremely* lossy. What you are
talking about is the *decompression* process.

No, Im talking about the encoding process. IIRC the compression used is
huffman or LZW (or some such). This is done AFTER the encoding process.

The encoding is part of the compression process. Don't be
disingenuous.

The content of the source has f*ck all to do with linearity.

That is about the dumbest thing you've said yet - which is an
achievement in itself!

Linearity is a property of the system, not the data you put into it.

Which part of 'garbage in, garbage out' did you fail to understand?
--

Stewart Pinkerton | Music is Art - Audio is Engineering

In article , Glenn Booth
wrote:
Hi,

In message , Ian Molton
writes

No, Im talking about the encoding process. IIRC the compression used is
huffman or LZW (or some such). This is done AFTER the encoding process.

It's been a long time, but if I recall, the process goes something like:

Decompose the signal into frames. Analyse to determine the spectral
energy distribution and break signal
into sub-bands.
Allocate bits to each sub-band according to the data rate set in
codec. Compare frequency distribution to psychoacoustic models stored
in the
codec, and discard data that would not be perceived due to masking etc.
(This bit is lossy).
Huffman code the bitstream, compressing redundancies in the sample.
(Not lossy - it assigns 'symbols' to bit sequences to achieve
compression without loss).
Finally, format the bitstream.

I'm stretching my memory here, so I could be incorrect on the order of
things, and the above is way oversimplified. If anyone can be bothered,
the real story is at http://www.mpeg.org/MPEG/audio.html

IIRC the above description is fairly accurate. There is also some loss due
to 'requantisation' where components that are regarded as 'unimportant, but
worth keeping' may be stored with relatively few bits. Hence in terms of
loss of details, the behaviour is slightly more compex than 'keep some
details and completely discard others'. But information is lost.

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html

On Fri, 16 Jan 2004 23:43:48 +0000 (UTC)
(Stewart Pinkerton) wrote:

No, Im talking about the encoding process. IIRC the compression used
is huffman or LZW (or some such). This is done AFTER the encoding
process.

The encoding is part of the compression process. Don't be
disingenuous.

I wasnt trying to be. Someone said the encoding process was irrelevant,
all that mattered was the compression. Ah, heres the quote - Kurt
Hamster wrote:

'******** to the encoding, the fact remains there are audible
differences between compressed files (at any bit rate) and
uncompressed audio.'

The content of the source has f*ck all to do with linearity.

That is about the dumbest thing you've said yet - which is an
achievement in itself!

Linearity is a property of the system, not the data you put into it.

Which part of 'garbage in, garbage out' did you fail to understand?

None of it. And a linear system will reproduce garbage without
distortion, although Im failing to see your point here (do you have
one?)

So, I repeat:

'Linearity is a property of the system, not the data you put
into it.'

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with
ketchup.