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<div class="headertitle"><div class="title">DownScalingAlgorithms<div class="ingroups"><a class="el" href="group___scaling_algorithms.html">ScalingAlgorithms</a></div></div></div>
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<p>Algorithms suitable for downscaling.
<a href="#details">More...</a></p>
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<tr class="heading"><td colspan="2"><h2 class="groupheader"><a id="func-members" name="func-members"></a>
Functions</h2></td></tr>
<tr class="memitem:ga3c46f2bebfe5add39863df37237d5dc9" id="r_ga3c46f2bebfe5add39863df37237d5dc9"><td class="memTemplParams" colspan="2">template&lt;typename ImageView &gt; </td></tr>
<tr class="memitem:ga3c46f2bebfe5add39863df37237d5dc9"><td class="memTemplItemLeft" align="right" valign="top">void&#160;</td><td class="memTemplItemRight" valign="bottom"><a class="el" href="group___down_scaling_algorithms.html#ga3c46f2bebfe5add39863df37237d5dc9">scale_lanczos</a> (ImageView input_view, ImageView output_view, std::ptrdiff_t a)</td></tr>
<tr class="memdesc:ga3c46f2bebfe5add39863df37237d5dc9"><td class="mdescLeft">&#160;</td><td class="mdescRight">Complete Lanczos algorithm. <br /></td></tr>
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<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<p>Algorithms suitable for downscaling. </p>
<p>These algorithms provide best results when used for downscaling. Using for upscaling will probably provide less than good results.</p>
<p>a single step of lanczos downscaling</p>
<p>Use this algorithm to scale down source image into a smaller image with reasonable quality. Do note that having a look at the output once is a good idea, since it might have ringing artifacts. </p>
<h2 class="groupheader">Function Documentation</h2>
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<h2 class="memtitle"><span class="permalink"><a href="#ga3c46f2bebfe5add39863df37237d5dc9">&#9670;&#160;</a></span>scale_lanczos()</h2>
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template&lt;typename ImageView &gt; </div>
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<td class="memname">void scale_lanczos </td>
<td>(</td>
<td class="paramtype">ImageView&#160;</td>
<td class="paramname"><em>input_view</em>, </td>
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<td class="paramtype">ImageView&#160;</td>
<td class="paramname"><em>output_view</em>, </td>
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<td class="paramtype">std::ptrdiff_t&#160;</td>
<td class="paramname"><em>a</em>&#160;</td>
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<p>Complete Lanczos algorithm. </p>
<p>This algorithm does full pass over resulting image and convolves pixels from original image. Do note that it might be a good idea to have a look at test output as there might be ringing artifacts. Based on wikipedia article: <a href="https://en.wikipedia.org/wiki/Lanczos_resampling">https://en.wikipedia.org/wiki/Lanczos_resampling</a> with standardinzed cardinal sin (sinc) </p>
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