):
The number of blur passes to apply. Default is <strong>1</strong>.
Must be a <strong>positive integer</strong> (<cite>npass &gt; 0</cite>).
Multiple passes result in a stronger blur effect but may increase processing time.</p></li>
</ul>
<p><strong>Returns</strong></p>
<ul class="simple">
<li><p><strong>None</strong> â€“ The function modifies <cite>surface_</cite> in place, with no return value.</p></li>
</ul>
<p><strong>Raises</strong></p>
<ul class="simple">
<li><p><strong>TypeError</st