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donkey7



Joined: 31 Jan 2005
Posts: 127
Location: Poland, Malopolska
donkey7
how the recovery volumes works?

i have seen they in winrar and tested it. if you have n recovery volumes then you can recover *any* n missing volumes. at first sight it seems to be a magic Smile

i have thought a little about that. i invented a way to recover only one volume. you can do this in this way:
- xor all volumes (i mean xor first bytes from all volumes, then xor second bytes from all volumes...) and you get recovery volume,
- you can recover any missing volume by xoring all volumes you have (including recovery volume)
- you can recover only one missing volume,

the algorithm that recover any missing n volumes is included in unrar sources in files recvol.cpp and rs.cpp.

can you explain this algorithm for me in easy way?

sorry for bad english.

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Keep coding!
Post 30 Jun 2005, 12:54
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donkey7



Joined: 31 Jan 2005
Posts: 127
Location: Poland, Malopolska
donkey7
hmm, difficult question ?? Wink
Post 05 Jul 2005, 20:37
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f0dder



Joined: 19 Feb 2004
Posts: 3170
Location: Denmark
f0dder
Probably similar to .par files - http://www.slyck.com/ng.php?page=6
Post 05 Jul 2005, 20:46
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donkey7



Joined: 31 Jan 2005
Posts: 127
Location: Poland, Malopolska
donkey7
thanks, very much appreciated. this was exactly what i want.
Post 07 Jul 2005, 20:56
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f0dder



Joined: 19 Feb 2004
Posts: 3170
Location: Denmark
f0dder
glad to help Smile
Post 07 Jul 2005, 23:22
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