Re: Transparent compression in the FS

[John Bradford]

Quote from Robert Love <rml@xxxxxxxxx>:
> On Thu, 2003-10-16 at 14:56, Richard B. Johnson wrote:
> 
> > No! Not true. 'lossy' means that you can't recover the original
> > data. Some music compression and video compression schemes are
> > lossy. If you can get back the exact input data, it's not lossy.
> 
> ...and with an N-bit hash of M bits of data, where N<M, you cannot
> recover the original data...

I think the confusion has arisen because I said that you can't
compress N values in to <N values.  This is somewhat ambiguous, and
can be taken to mean either:

1. You can't loss-lessly compress N arbitrary values, in to less than
N arbitrary values using a certain mathematical transformation.

or

2. You can't loss-lessly compress all N combinations of M bits, in to
less than M bits, using any mathematical transformation.

Obviously interpretation 1 is incorrect, and interpretation 2 is
correct.

John.
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