n class="n">h2</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span> <span class="n">C2</span> <span class="o">=</span> <span class="kc">None</span><span class="p">,</span> <span class="n">htype</span> <span class="o">=</span> <span class="s1">&#39;deg&#39;</span><span class="p">):</span>
<span class="w">    </span><span class="sd">&quot;&quot;&quot;</span>
<span class="sd">    Compute a hue difference, dH = 2*C1*C2*sin(dh/2)</span>
<span class="sd">    </span>
<span class="sd