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<title>Magick++ API: PixelPacket</title>
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<h1 align="center">PixelPacket Structure</h1>
<p style="margin-bottom: 0cm">The <i>PixelPacket</i> structure is used to represent pixels in ImageMagick. ImageMagick may be compiled to support 32 or 64 bit pixels. The size of PixelPacket is controlled by the value of the <i>QuantumDepth</i> define. The default is 64 bit pixels, which provide the best accuracy. If memory consumption must be minimized, or processing time must be minimized, then ImageMagick may be compiled with QuantumDepth=8. The following table shows the relationship between <i>QuantumDepth</i>, the type of <i>Quantum</i>, and the overall <i>PixelPacket</i> size.</p>
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<p align="center" style="margin-bottom: 0cm"><b>Effect Of QuantumDepth Values</b></p>
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<p align="center"><b>QuantumDepth</b></p></td>
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<p align="center"><b>Quantum Type</b></p></td>
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<p align="center"><b>PixelPacket Size</b></p></td></tr>
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<td width="101">
<p align="center">8</p></td>
<td width="99">
<p align="center">unsigned char</p></td>
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<p align="center">32 bits</p></td></tr>
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<td width="101">
<p align="center">16</p></td>
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<p align="center">unsigned short</p></td>
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<p align="center">64 bits</p></td></tr></table></center>
<p style="margin-bottom: 0cm">The members of the <i>PixelPacket</i> structure, and their interpretation, are shown in the following table:</p>
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<p align="center" style="margin-bottom: 0cm"><b>PixelPacket Structure Members</b></p>
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<p align="center"><b>Member</b></p></td>
<td rowspan="2" width="50">
<p align="center"><b>Type</b></p></td>
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<p align="center"><b>Interpretation</b></p></td></tr>
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<td width="102">
<p align="center"><a href="Enumerations.html#ColorspaceType">RGBColorspace</a></p></td>
<td width="152">
<p align="center"><a href="Enumerations.html#ColorspaceType">RGBColorspace</a> + <a href="Image++.html#matte">matte</a></p></td>
<td width="119">
<p align="center"><a href="Enumerations.html#ColorspaceType">CMYKColorspace</a></p></td></tr>
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<td width="58">
<p><font size="2">red</font></p></td>
<td width="50">
<p><font size="2">Quantum</font></p></td>
<td width="102">
<p><font size="2">Red</font></p></td>
<td width="152">
<p><font size="2">Red</font></p></td>
<td width="119">
<p><font size="2">Cyan</font></p></td></tr>
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<td width="58">
<p><font size="2">green</font></p></td>
<td width="50">
<p><font size="2">Quantum</font></p></td>
<td width="102">
<p><font size="2">Green</font></p></td>
<td width="152">
<p><font size="2">Green</font></p></td>
<td width="119">
<p><font size="2">Magenta</font></p></td></tr>
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<td width="58">
<p><font size="2">blue</font></p></td>
<td width="50">
<p><font size="2">Quantum</font></p></td>
<td width="102">
<p><font size="2">Blue</font></p></td>
<td width="152">
<p><font size="2">Blue</font></p></td>
<td width="119">
<p><font size="2">Yellow</font></p></td></tr>
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<td width="58">
<p><font size="2">opacity</font></p></td>
<td width="50">
<p><font size="2">Quantum</font></p></td>
<td width="102">
<p><font size="2">Ignored</font></p></td>
<td width="152">
<p><font size="2">Opacity</font></p></td>
<td width="119">
<p><font size="2">Ignored</font></p></td></tr></table></center>
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