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<font size="+3"><b>dvdisaster</b></font>
<i>Version 0.72 (pl1)</i>
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<font size="+3"> </font><a href="http://dvdisaster.net/en/">To the Internet version</a>
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<font size="-1"><b>Contents</b></font>
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<tr><td colspan=3><font size="-1"><a href="index.html">Overview</a></font></td></tr>
<tr><td valign="top" width="1%">·</td><td colspan=2><font size="-1">Examples of the error correction</font></td></tr>
<tr><td valign="top" width="1%">·</td><td colspan=2><font size="-1"><a href="index20.html">dvdisaster complements quality scans</a></font></td></tr>
<tr><td valign="top" width="1%">·</td><td colspan=2><font size="-1"><a href="index30.html">Pro and con of dvdisaster</a></font></td></tr>
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<h3>Examples of the error correction</h3>
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<b>Recovery of aged media.</b> The medium processed here has become
discolored and partly unreadable in its outer region. A surface scan
yields about 23.000 unreadable sectors of 342.000 sectors total; resulting
in about 7,2% defective sectors.
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<tr><td align="center">Screen shot: Reading the defective medium.</td></tr>
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<b>Repairing the defective image.</b> The resulting image is still incomplete
since about 23.000 sectors could not be read. These sectors are now
reconstructed using
the error correction data created with dvdisaster.
During the recovery a maximum of 20 errors
per error correction block is encountered. This results in a peak
error correction load of 63%, meaning that this degree of damage is handled well
by error correction data created with default settings.
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<tr><td><font size="-1">Repairing the defective image.</font></td></tr>
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<b>Recovery needs error correction data:</b> The recovery process described above uses
error correction ("ecc") data.
Think of this data as a special
form of backup data (it needs less space than a normal backup, though).
Like an ordinary backup, the ecc data needs to be created
<i>before</i> the medium goes defective.<p>
So if you have a defective medium but never created ecc data for it - sorry,
your data is probably lost.<p>
<a href="index20.html">Why quality scans won't suffice...</a>
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<table cellpadding="10"><tr><td><a href="http://dvdisaster.net/legacy/en/index.html"><font size="-1">Old documentation (V0.70)</font></a></td></tr></table>
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<i> Copyright 2004-2009 Carsten Gnörlich.<br>
Verbatim copying and distribution of this entire article is permitted in any medium, provided this notice is preserved.
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distrib
>
Mandriva
>
2010.0
>
i586
>
media
>
contrib-release
>
by-pkgid
>
93f0f6b9dba72659e97f5e08b2db3f56
>
files
>
1022
