 class="keywordtype">void</span></div><div class="line"><a name="l00027"></a><span class="lineno">   27</span>&#160;        &gt;</div><div class="line"><a name="l00028"></a><span class="lineno">   28</span>&#160;<span class="keyword">struct </span>row_buffer_helper</div><div class="line"><a name="l00029"></a><span class="lineno">   29</span>&#160;{</div><div class="line"><a name="l00030"></a><span class="lineno">   30</span>&#160;    <span class="keyword">using</span> element_t = Pixel;</div><div class="lin