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<h1><a class="anchor" id="rgb2pct">rgb2pct.py </a></h1><p>Convert a 24bit RGB image to 8bit paletted</p>
<h2><a class="anchor" id="rsynopsis">
SYNOPSIS</a></h2>
<div class="fragment"><pre class="fragment">
rgb2pct.py [-n colors] [-of format] source_file dest_file
</pre></div><h2><a class="anchor" id="rdescription">
DESCRIPTION</a></h2>
<p>This utility will compute an optimal pseudo-color table for a given RGB image using a median cut algorithm on a downsampled RGB histogram. Then it converts the image into a pseudo-colored image using the color table. This conversion utilizes Floyd-Steinberg dithering (error diffusion) to maximize output image visual quality.</p>
<dl>
<dt><b>-n</b> <em>colors</em>:</dt>
<dd>Select the number of colors in the generated color table. Defaults to 256. Must be between 2 and 256. </dd>
<dt><b>-of</b> <em>format</em>:</dt>
<dd>Format to generated (defaults to GeoTIFF). Same semantics as the <b>-of</b> flag for gdal_translate. Only output formats supporting pseudocolor tables should be used. </dd>
<dt><em>source_file</em>:</dt>
<dd>The input RGB file. </dd>
<dt><em>dest_file</em>:</dt>
<dd>The output pseudo-colored file that will be created. </dd>
</dl>
<p>NOTE: rgb2pct.py is a Python script, and will only work if GDAL was built with Python support. </p>
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