t parameter is <code/>PatchRelativeSigma</code>
which expresses the amount of smoothing applied to the image in the
normalised patch frame. By default this is set to 1.0, but can be
reduced to get sharper patches. Of course, the amount of
smoothing is bounded below by the resolution of the input image: a
smoothing of, say, less than half a pixel cannot be recovered due to
the limited sampling rate of the latter. Moreover, the patch must be
sampled finely enough to avoid aliasing (see next).</p>

<p>The last