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<span class="fxxl"><b>dvdisaster</b></span>
<i>Version 0.72.6 / 0.79 (devel-3)</i>
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<span class="fxxl"> </span><a href="http://dvdisaster.net/en/">To the Internet version</a>
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<tr><td style="width:1%; vertical-align:top;">·</td><td colspan=2><span class="fs"><a href="index10.html">Examples of the error correction</a></span></td></tr>
<tr><td style="width:1%; vertical-align:top;">·</td><td colspan=2><span class="fs">dvdisaster complements quality scans</span></td></tr>
<tr><td style="width:1%; vertical-align:top;">·</td><td colspan=2><span class="fs"><a href="index30.html">Pro and con of dvdisaster</a></span></td></tr>
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<h3 class="top">dvdisaster as a complement to quality scans</h3>
<a href="qa.html#pipo">Quality scans</a>, e.g. C2 error or PI/PO scans are a valuable
tool for testing the results of the media writing process.<p>
But quality scans are <b>not</b> a reliable means of <b>predicting
the lifetime</b> of optical media. <br>
Consider we are looking for the right time
to copy a worn-out medium onto a new one:
<ul>
<li>Too early: Copying media because of a bad quality scan is cost-ineffective.
Sometimes such media remain readable much longer than expected.<p></li>
<li>Too late: When the quality scan reveals unreadable sectors some
data has already been lost.<p></li>
<li>Right before the medium fails: The ideal case, but how to tell?
</ul>
However, we could do it the dvdisaster way:
<ul>
<li><a href="howtos20.html">Create error correction data</a> for the medium.<p></li>
<li><a href="howtos10.html">Scan the medium</a> regularly. Use it until the first read errors occur.<p></li>
<li><a href="howtos40.html">Recover</a> the read errors <a href="howtos40.html">using the error correction data</a>.
Write the recovered image to a new medium.</li>
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<a href="index30.html">Pro and con of dvdisaster at a glance...</a>
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<i> Copyright 2004-2014 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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