How to calculate second order derivative on image
<p>I want to calculate second and third order derivative on image. I believe the best way is to derive a gaussian filter and then convolve with image.</p>

<p>For example for second order derive gaussian twice and convolve with image or for third order as well.</p>

<p>But another way that I want to ask you is, can we calculate second order with convolving two first derivative gaussian sequentially with image?
for ex. for ixx
we compute:</p>

<pre><code>[ix,iy]=imgradientxy(i);

[ixx,ixy]=imgradientxy(ix);
</code></pre>

<p>Is this true for calculating second order derivative?</p>