">#ifdef BOOST_GIL_IO_ENABLE_GRAY_ALPHA</span></div><div class="line"><a name="l00056"></a><span class="lineno">   56</span>&#160;<span class="keyword">using</span> gray_alpha8_pixel_t = pixel&lt;uint8_t, gray_alpha_layout_t&gt;;</div><div class="line"><a name="l00057"></a><span class="lineno">   57</span>&#160;<span class="keyword">using</span> gray_alpha16_pixel_t = pixel&lt;uint16_t, gray_alpha_layout_t&gt;;</div><div class="line"><a name="l00058"></a><span class="lineno">   58</span>&#160;<span class="k