126 lines
5.2 KiB
PHP
126 lines
5.2 KiB
PHP
<?php
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# dvdisaster: English homepage translation
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# Copyright (C) 2004-2012 Carsten Gnörlich
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#
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# UTF-8 trigger: äöüß
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#
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# Include our PHP sub routines, then call begin_page()
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# to start the HTML page, insert the header,
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# navigation and news if appropriate.
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require("../include/dvdisaster.php");
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begin_page();
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?>
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<!-- Insert actual page content below -->
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<h3 class="top">Using dvdisaster the wrong way</h3>
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Joe bets on his media keeping their content
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without additional protection.<p>
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<table width="100%">
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<tr>
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<td class="w15p">10. Feb. 2004</td>
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<td class="w65x"><img src="../images/good-cd.png" alt="Icon: Good medium (without read errors)"></td>
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<td class="w65x"><img src="../images/good-cd.png" alt="Icon: Good medium (without read errors)"></td>
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<td>Joe creates two CDs containing important data. But he does not
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make any provisions against data loss on those media.</td>
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</tr>
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<tr><td colspan="4"> <hr> </td></tr>
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<tr>
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<td>14. May 2005</td>
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<td><img class="valignt" src="../images/good-cd.png" alt="Icon: Good medium (without read errors)"></td>
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<td><img class="valignt" src="../images/good-cd.png" alt="Icon: Good medium (without read errors)"></td>
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<td>Joe uses his CDs regularly. After one year they are still perfectly
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readable.</td>
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</tr>
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<tr><td colspan="4"> <hr> </td></tr>
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<tr>
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<td>19. Aug 2007</td>
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<td><img class="valignt" src="../images/bad-cd.png" alt="Icon: Damaged medium (partially unreadable)"></td>
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<td><img class="valignt" src="../images/good-cd.png" alt="Icon: Good medium (without read errors)"></td>
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<td>After two more years Joe notices that some data on one CD is no
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longer readable.</td>
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</tr>
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<tr>
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<td align="right"><a href="howtos10.php">scanning</a></td>
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<td align="center"><img class="valignt" src="../images/down-arrow.png" alt="Icon: Arrow down"></td>
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<td align="center"><img class="valignt" src="../images/down-arrow.png" alt="Icon: Arrow down"></td>
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<td></td>
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</tr>
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<tr>
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<td>20. Aug 2007</td>
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<td><img class="valignt" src="../images/bad-cd.png" alt="Icon: Damaged medium (partially unreadable)"></td>
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<td><img class="valignt" src="../images/bad-cd.png" alt="Icon: Damaged medium (partially unreadable)"></td>
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<td>Joe downloads dvdisaster and performs
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<a href="howtos10.php">a read error scan</a>.
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He finds out that the CD contains 25000 unreadable sectors. A scan
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of the second CD reveals that it has developed 1500 unreadable sectors
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gone unnoticed so far. </td>
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</tr>
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<tr>
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<td align="right">reading</td>
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<td align="center"><img class="valignt" src="../images/down-arrow.png" alt="Icon: Arrow down"></td>
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<td align="center"><img class="valignt" src="../images/down-arrow.png" alt="Icon: Arrow down"></td>
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<td></td>
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</tr>
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<tr><td colspan="4"> <p> </td></tr>
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<tr>
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<td>21. Aug 2007</td>
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<td><img class="valignt" src="../images/bad-image.png" alt="Icon: Partial image"></td>
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<td><img class="valignt" src="../images/bad-image.png" alt="Icon: Partial image"></td>
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<td>Joe uses dvdisaster to
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read as much sectors as possible from the
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defective media. But since he does not have error correction data
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there is no way of recalculating the unreadable sectors.</td>
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</tr>
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<tr>
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<td align="right">many reading<br>attempts</td>
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<td align="center"><img class="valignt" src="../images/down-arrow.png" alt="Icon: Arrow down"></td>
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<td align="center"><img class="valignt" src="../images/down-arrow.png" alt="Icon: Arrow down"></td>
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<td></td>
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</tr>
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<tr><td colspan="4"> <p> </td></tr>
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<tr>
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<td>05. Sep 2007</td>
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<td><img class="valignt" src="../images/bad-image.png" alt="Icon: Partial image"></td>
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<td><img class="valignt" src="../images/good-image.png" alt="Icon: Complete image"></td>
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<td>Joe takes advantage of dvdisaster's feature to complete images
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through multiple reading passes. He moves the defective images to
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several computers to perform reading attempts with different drives.
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After two weeks of trying at least all missing sectors from the second
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CD have been read. However on the first CD still 21000 sectors
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remain unreadable by any drive he tried.</td>
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</tr>
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<tr>
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<td align="right">only one CD<br>recovered</td>
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<td align="center"><img class="valignt" src="../images/down-arrow.png" alt="Icon: Arrow down"></td>
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<td align="center"><img class="valignt" src="../images/down-arrow.png" alt="Icon: Arrow down"></td>
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<td></td>
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</tr>
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<tr><td colspan="4"> <p> </td></tr>
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<tr>
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<td>06. Sep 2007</td>
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<td><img class="valignt" src="../images/bad-cd.png" alt="Icon: Damaged medium (partially unreadable)"></td>
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<td><img class="valignt" src="../images/good-cd.png" alt="Icon: Good medium (without read errors)"></td>
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<td>Joe dismisses the first CD as unrecoverable and considers himself lucky
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to have a complete image from the second CD again.
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However if he had created error correction data in time, he'd probably <sup>1)</sup>
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saved two weeks of reading attempts and recovered the contents from both CDs.</td></tr>
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</table>
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<hr>
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<sup>1)</sup>The error correction assumes a typical aging process.
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If the CD gets severely damaged it becomes unrecoverable even with
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error correction data. Do not rely on dvdisaster alone for protecting
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important data; instead employ additional measures like creating
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additional copies on different types of media.
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<!-- do not change below -->
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<?php
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# end_page() adds the footer line and closes the HTML properly.
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end_page();
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?>
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