ent_reference_type&lt;const pixel&lt;ChannelValue,Layout&gt;, K&gt; {
<a name="l00169"></a>00169     <span class="keyword">typedef</span> <span class="keyword">typename</span> channel_traits&lt;ChannelValue&gt;::const_reference type;
<a name="l00170"></a>00170 };
<a name="l00171"></a>00171 
<a name="l00172"></a>00172 <span class="keyword">template</span> &lt;<span class="keyword">typename</span> ChannelValue, <span class="keyword">typename</span> Layout, <span class="keywordtype">int</span> K&gt;  
<a name=