Data formats was Re: Rescue of data from Pioneer 10 & 11 tapes at JPL needed.Vintagecomputers slated for demolition.

[Randy McLaughlin]

From: "Nico de Jong" <nico at FARUMDATA.DK>
Sent: Wednesday, June 08, 2005 1:28 PM


> > > ... but I dont have the foggiest idea
> > >whether the data is "decodeable". The best way to save the data, is to
> get a
> > >copy of the program which wrote the data in the first place. I have the
> > >funny feeling that the data is written in _huge_ blocks.
> > >
>
> > Two things needed, a tape drive and something to interpret
> > the data. Many times, important information about the
> > data is external to the recorded data on the tape.
> >
> > Like pdf or zip files, I suspect that some pieces may
> > be missing to recover the information. I doubt that
> > the major issue is the obsolete computer.
>
> I quite agree, in a broad sense. I'm presently doing some digging in files
> coming from an 8" floppy originating from a CT Scanner. The data is
> perfectly readable, but part of the data is compressed, and no details on
> decompression are available. And the manufacturer cant/wont assist.
>
> Anyway, the first thing to do is to copy things to a modern media; data
> manipulation can be worried about later.
>
> So, let's try to read a tape...
>
> Nico

The problem is if the data format is not documented.  Adobe understood that
when they developed PostScript and PDF's, both are well documented.

If you have data with an unknown format then you can speend years trying to
understand it, Egyptian hieroglyphs were made readable by using the Rosetta
stone.  Adobe's documentation of both the PostScript and PDF formats are the
rosetta stones for their respective formats.

The information written in hieroglyphics as been translated to current
languages including english.  The original hieroglyphs are kept, I expect
PDF's to be treated similarly.  In the future as newer formats are created I
expect automated proceedures will exist to translate PDF's to newer formats
maybe akin to the babel project.

Some have recommended use PostScript as a document archival medium.  Adobe
knows the limitations of PostScript better than anyone else and they decided
that is is not the right format.  They created the PDF format for the exact
task at hand.

I would never post a document as a series of individual pages.  PDF is the
structure that defines what the document is.

I expect that in the future many better systems will not only be developed
but will have wide spread acceptance.  Right now only PDF's have universal
acceptance.


Randy
www.s100-manuals.com