On 1 May 2000, Stainless Steel Rat wrote:
> * "Jiawei Ye" <[EMAIL PROTECTED]> on Mon, 01 May 2000
> | If "compression" is defined as you did (you defined CD-DA as
> | "compression"), no digital mobile phone system will exist in the US,
> | 'cause "the FCC does not allow compression or encryption"
>
> There is no One True Definition of compression. The definition of
But there are many incorrect ones...
> compression used in the communications industry has a narrow scope. To the
> comms guys and the FCC, compression is an algorithmic transformation of
> clear data into coded data, and data loss is usually not allowed. To them,
Key word there. "usually". Which would imply that it is sometimes
allowed. Hmm. Also, since CDMA does lossy compression, and is allowed by
the FCC, well, that would seem to suggest that the comms guys you like to
talk about so much seem quite happy with lossy compression. The GSM comms
guys outside the US definitely seem happy with that...
> "lossy compression" is an oxymoron. This is the correct definition to use
> when discussing communications systems, which is what I was doing.
Compression was traditionally lossless because originally nobody knew how
to make lossy compression systems that worked well. Originally all
compression was lossless; now compression is divied into lossy and
lossless.
> By that definition, ATRAC is not compression. But by our consensus, ATRAC
> is compression. We have decided that the comms definition is too narrow
"our" includes professionals in the field. So I figure that we're safe in
considering it a good definition.
> for our needs, so we use a different definition, one with a broader scope.
Newer, not just different.
> Instead of an algorithmic transformation, compression is the process of
ATRAC is an algorithm. GSM is an algorithm. MPEG is an algorithm.
> reducing data so as to require less space to store or less carrier capacity
...reducing data so as to require less digital bits to transmit. The
increase in carrier capacity or decrease in storage space are just side
effects; the critical reason it's considered compression is because there
are less bits needed to transmit the signal.
> to transmit. By this definition, the sampling rate cutoff used by PCS and
> GSM is considered to be a compression scheme.
You are making the same mistake over and over. You are trying to look at
analog and digital signals and claiming that because some particular way
of encoding analog signals may take up more space than another particular
way of encoding digital signals, therefore it's a form of compression.
Analog to digital covnersion is NOT compression. CITE A SOURCE if you are
going to continue to assert this.
Sadly, I haven't found a source that stated that ADC was not compression;
most people in the field would never even consider that as a possibility.
So, if you wish to continue to assert something that the rest of the list
disagrees with, perhaps you could just find us somebody else who agrees
with you? It's getting tiring to see you constantly making incorrect
claims and arguing "I think it should be this way!". It isn't. Sorry.
> So, back to the original point. Is the sampling rate cutoff used by CD-DA
> sampling a form of lossy compression? By the very strict definition of the
> comms industry, no. By the very broad definition of the MD community, yes.
By your incorrect extrapolation of our definition, yes. But you do appear
to be the only one here who appears to believe this.
I must again point out that the creators of ATRAC, and many other
standards such as MPEG believe that their systems are forms of
compression. If professionals in the field of data compression believe
that lossy compression is still compression, you'd better have more reason
to argue than "I disagree".
It's amusing, it was originally suggested that I take the debate to this
list so that my innacurate information would be corrected by the list
members. So far it would seem that most of the corrections have been made
to rat's info, and by many people other than me...
gopi.
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