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6. pixfmt-nv24.xml

    <refentry>
      <refmeta>
	<refentrytitle>V4L2_PIX_FMT_NV24 ('NV24'), V4L2_PIX_FMT_NV42 ('NV42')</refentrytitle>
	&manvol;
      </refmeta>
      <refnamediv>
	<refname id="V4L2-PIX-FMT-NV24"><constant>V4L2_PIX_FMT_NV24</constant></refname>
	<refname id="V4L2-PIX-FMT-NV42"><constant>V4L2_PIX_FMT_NV42</constant></refname>
	<refpurpose>Formats with full horizontal and vertical
chroma resolutions, also known as YUV 4:4:4. One luminance and one
chrominance plane with alternating chroma samples as opposed to
<constant>V4L2_PIX_FMT_YVU420</constant></refpurpose>
      </refnamediv>
      <refsect1>
	<title>Description</title>

	<para>These are two-plane versions of the YUV 4:4:4 format. The three
	components are separated into two sub-images or planes. The Y plane is
	first, with each Y sample stored in one byte per pixel. For
	<constant>V4L2_PIX_FMT_NV24</constant>, a combined CbCr plane
	immediately follows the Y plane in memory. The CbCr plane has the same
	width and height, in pixels, as the Y plane (and the image). Each line
	contains one CbCr pair per pixel, with each Cb and Cr sample stored in
	one byte. <constant>V4L2_PIX_FMT_NV42</constant> is the same except that
	the Cb and Cr samples are swapped, the CrCb plane starts with a Cr
	sample.</para>

	<para>If the Y plane has pad bytes after each row, then the CbCr plane
	has twice as many pad bytes after its rows.</para>

	<example>
	  <title><constant>V4L2_PIX_FMT_NV24</constant> 4 &times; 4
pixel image</title>

	  <formalpara>
	    <title>Byte Order.</title>
	    <para>Each cell is one byte.
		<informaltable frame="none">
		<tgroup cols="9" align="center">
		  <colspec align="left" colwidth="2*" />
		  <tbody valign="top">
		    <row>
		      <entry>start&nbsp;+&nbsp;0:</entry>
		      <entry>Y'<subscript>00</subscript></entry>
		      <entry>Y'<subscript>01</subscript></entry>
		      <entry>Y'<subscript>02</subscript></entry>
		      <entry>Y'<subscript>03</subscript></entry>
		    </row>
		    <row>
		      <entry>start&nbsp;+&nbsp;4:</entry>
		      <entry>Y'<subscript>10</subscript></entry>
		      <entry>Y'<subscript>11</subscript></entry>
		      <entry>Y'<subscript>12</subscript></entry>
		      <entry>Y'<subscript>13</subscript></entry>
		    </row>
		    <row>
		      <entry>start&nbsp;+&nbsp;8:</entry>
		      <entry>Y'<subscript>20</subscript></entry>
		      <entry>Y'<subscript>21</subscript></entry>
		      <entry>Y'<subscript>22</subscript></entry>
		      <entry>Y'<subscript>23</subscript></entry>
		    </row>
		    <row>
		      <entry>start&nbsp;+&nbsp;12:</entry>
		      <entry>Y'<subscript>30</subscript></entry>
		      <entry>Y'<subscript>31</subscript></entry>
		      <entry>Y'<subscript>32</subscript></entry>
		      <entry>Y'<subscript>33</subscript></entry>
		    </row>
		    <row>
		      <entry>start&nbsp;+&nbsp;16:</entry>
		      <entry>Cb<subscript>00</subscript></entry>
		      <entry>Cr<subscript>00</subscript></entry>
		      <entry>Cb<subscript>01</subscript></entry>
		      <entry>Cr<subscript>01</subscript></entry>
		      <entry>Cb<subscript>02</subscript></entry>
		      <entry>Cr<subscript>02</subscript></entry>
		      <entry>Cb<subscript>03</subscript></entry>
		      <entry>Cr<subscript>03</subscript></entry>
		    </row>
		    <row>
		      <entry>start&nbsp;+&nbsp;24:</entry>
		      <entry>Cb<subscript>10</subscript></entry>
		      <entry>Cr<subscript>10</subscript></entry>
		      <entry>Cb<subscript>11</subscript></entry>
		      <entry>Cr<subscript>11</subscript></entry>
		      <entry>Cb<subscript>12</subscript></entry>
		      <entry>Cr<subscript>12</subscript></entry>
		      <entry>Cb<subscript>13</subscript></entry>
		      <entry>Cr<subscript>13</subscript></entry>
		    </row>
		    <row>
		      <entry>start&nbsp;+&nbsp;32:</entry>
		      <entry>Cb<subscript>20</subscript></entry>
		      <entry>Cr<subscript>20</subscript></entry>
		      <entry>Cb<subscript>21</subscript></entry>
		      <entry>Cr<subscript>21</subscript></entry>
		      <entry>Cb<subscript>22</subscript></entry>
		      <entry>Cr<subscript>22</subscript></entry>
		      <entry>Cb<subscript>23</subscript></entry>
		      <entry>Cr<subscript>23</subscript></entry>
		    </row>
		    <row>
		      <entry>start&nbsp;+&nbsp;40:</entry>
		      <entry>Cb<subscript>30</subscript></entry>
		      <entry>Cr<subscript>30</subscript></entry>
		      <entry>Cb<subscript>31</subscript></entry>
		      <entry>Cr<subscript>31</subscript></entry>
		      <entry>Cb<subscript>32</subscript></entry>
		      <entry>Cr<subscript>32</subscript></entry>
		      <entry>Cb<subscript>33</subscript></entry>
		      <entry>Cr<subscript>33</subscript></entry>
		    </row>
		  </tbody>
		</tgroup>
		</informaltable>
	      </para>
	  </formalpara>
	</example>
      </refsect1>
    </refentry>