Re: [LAD] Better lossless compressions?

On Tuesday 22 June 2010, Adrian Knoth wrote:
>On Tue, Jun 22, 2010 at 06:38:45AM -0400, Gene Heskett wrote:
>> >from TFA:
>> >: Implemented in a DSP chip or microprocessor, this simple compressor
>> >: requires about 50 instructions per sample. However, lossless
>> >: compression ratios fall between 1.3:1 and 2:1 on baseband signals.
>> >
>> >So a size of 75% expected and on occasion down to 50% after
>> > compression. How is that compared to existing implementations?
>>
>> It was the lossless claim that got my attention, Jens. I am well aware
>> that current compressors can beat that at "acceptable" quality. But an
>> ogg at q7
>
>Jens was never talking about lossy "compression", which I call data
>reduction to avoid the ambiguity with real compression (as in ZIP).
>
>Lossless audio coding is nothing new, FLAC has been around for years.
>Your referenced codec achives 1.3:1 to 2:1. One can compare this to some
>values provided here:
>
>
> http://web.inter.nl.net/users/hvdh/lossless/lossless.htm
>
>
>These are all lossless codecs, and as one can see, only few manage to
>come close to 2:1 (50% compression).
>
>However, results for predictive coding (derivation based approaches)
>vary a lot depending on the input signal. As a rule of thumb, a pure
>sine is easier to predict than noise, which more or less is the
>mathematical equivalent of randomness (I'm sure Fons could go into
>detail here, if necessary).
>
>
>Long story short: I don't think your link contains something
>extra-ordinary, just another me-too approach of well-known techniques.
>It might save you a few bits, but you'll have to measure it. Fire up
>octave, load the matlab script, encode a wave file and compare it to
>FLAC.
>
>If your referenced algorithm gives striking results, then convince
>everybody to forget about FLAC and use this new algo instead. Let me
>predict that neither the first nor the latter will happen. ;)
>
>
>That's more or less the end of the story. Any further discussion would
>only make sense with measured results at hand.
>
>
>HTH

I certainly won't argue with that assessment. In truth, I had forgotten
about flac too, possibly another sign of CRS that goes with age.

-- 
Cheers, Gene
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
All components become obsolete. 
	-- Murphy's Computer Laws n�8
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