tiplication of
them.</p>

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<h1 id="tut.covdet.descr">Computing descriptors</h1>
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<p><code/><a href=../matlab/vl_covdet.html>vl_covdet</a></code> can also compute descriptors. Three are
supported so far: SIFT, LIOP and raw patches (from which any other
descriptor can be computed). To use this functionality simply add an
output argument:</p>

<div class="highlight"><pre>