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Re: PAR2 question

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Jim Leonard wrote:
) On Dec 27, 11:51?am, Industrial One <industrial_...@hotmail.com>
) wrote:
)> > You could "force" quickpar to "repair" the file if you lacked
)> > sufficient parity info, but there would be (in your above example) .1%
)> > bits incorrect all over the file. ?So what's worse: ?Knowing your file
)> > cannot be 100% repaired, or not knowing where in your file bits are
)> > incorrect?
)>
)> How do I do that? I don't see that option anywhere in Quickpar.
)
) By using quotes, I was implying a theoretical operation.  You cannot
) actually force quickpar (or PAR2, which is what you should actually be
) using since it's not memory-constrained, slow, or broken like quickpar
) is) to just make up parity information.

I'm not sure that it's even theoretically possible to have quickpar/par2
partially repair a file.  They use one CRC per block to identify the bad
blocks, and you need N 'good' blocks (of the N+M data+parity) to get the
original N data blocks back at all.  So too much damage is just too much
damage.


SaSW, Willem
-- 
Disclaimer: I am in no way responsible for any of the statements
            made in the above text. For all I know I might be
            drugged or something..
            No I'm not paranoid. You all think I'm paranoid, don't you !
#EOT

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Thread

PAR2 question Industrial One <industrial_one@hotmail.com> - 2011-12-25 13:25 -0800
  Re: PAR2 question Willem <willem@turtle.stack.nl> - 2011-12-25 23:16 +0000
    Re: PAR2 question Industrial One <industrial_one@hotmail.com> - 2011-12-26 08:33 -0800
      Re: PAR2 question Jim Leonard <mobygamer@gmail.com> - 2011-12-27 09:20 -0800
        Re: PAR2 question Industrial One <industrial_one@hotmail.com> - 2011-12-27 09:51 -0800
          Re: PAR2 question Jim Leonard <mobygamer@gmail.com> - 2011-12-29 09:10 -0800
            Re: PAR2 question Willem <willem@toad.stack.nl> - 2011-12-29 18:35 +0000
      Re: PAR2 question "Captain Obvious" <udodenko@users.sourceforge.net> - 2011-12-31 18:26 +0200

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