CooCenter-System-kernel/Documentation/DocBook/media/v4l/pixfmt-yuv410.xml

    <refentry>
      <refmeta>
	<refentrytitle>V4L2_PIX_FMT_YVU410 ('YVU9'), V4L2_PIX_FMT_YUV410 ('YUV9')</refentrytitle>
	&manvol;
      </refmeta>
      <refnamediv>
	<refname id="V4L2-PIX-FMT-YVU410"><constant>V4L2_PIX_FMT_YVU410</constant></refname>
	<refname id="V4L2-PIX-FMT-YUV410"><constant>V4L2_PIX_FMT_YUV410</constant></refname>
	<refpurpose>Planar formats with &frac14; horizontal and
vertical chroma resolution, also known as YUV 4:1:0</refpurpose>
      </refnamediv>
      <refsect1>
	<title>Description</title>

	<para>These are planar formats, as opposed to a packed format.
The three components are separated into three sub-images or planes.
The Y plane is first. The Y plane has one byte per pixel. For
<constant>V4L2_PIX_FMT_YVU410</constant>, the Cr plane immediately
follows the Y plane in memory. The Cr plane is &frac14; the width and
&frac14; the height of the Y plane (and of the image). Each Cr belongs
to 16 pixels, a four-by-four square of the image. Following the Cr
plane is the Cb plane, just like the Cr plane.
<constant>V4L2_PIX_FMT_YUV410</constant> is the same, except the Cb
plane comes first, then the Cr plane.</para>

	<para>If the Y plane has pad bytes after each row, then the Cr
and Cb planes have &frac14; as many pad bytes after their rows. In
other words, four Cx rows (including padding) are exactly as long as
one Y row (including padding).</para>

	<example>
	  <title><constant>V4L2_PIX_FMT_YVU410</constant> 4 &times; 4
pixel image</title>

	  <formalpara>
	    <title>Byte Order.</title>
	    <para>Each cell is one byte.
		<informaltable frame="none">
		<tgroup cols="5" 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>Cr<subscript>00</subscript></entry>
		    </row>
		    <row>
		      <entry>start&nbsp;+&nbsp;17:</entry>
		      <entry>Cb<subscript>00</subscript></entry>
		    </row>
		  </tbody>
		</tgroup>
		</informaltable>
	      </para>
	  </formalpara>

	  <formalpara>
	    <title>Color Sample Location.</title>
	    <para>
		<informaltable frame="none">
		<tgroup cols="7" align="center">
		  <tbody valign="top">
		    <row>
		      <entry></entry>
		      <entry>0</entry><entry></entry><entry>1</entry><entry></entry>
		      <entry>2</entry><entry></entry><entry>3</entry>
		    </row>
		    <row>
		      <entry>0</entry>
		      <entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
		      <entry>Y</entry><entry></entry><entry>Y</entry>
		    </row>
		    <row>
		      <entry></entry>
		    </row>
		    <row>
		      <entry>1</entry>
		      <entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
		      <entry>Y</entry><entry></entry><entry>Y</entry>
		    </row>
		    <row>
		      <entry></entry>
		      <entry></entry><entry></entry><entry></entry><entry>C</entry>
		      <entry></entry><entry></entry><entry></entry>
		    </row>
		    <row>
		      <entry>2</entry>
		      <entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
		      <entry>Y</entry><entry></entry><entry>Y</entry>
		    </row>
		    <row>
		      <entry></entry>
		    </row>
		    <row>
		      <entry>3</entry>
		      <entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
		      <entry>Y</entry><entry></entry><entry>Y</entry>
		    </row>
		  </tbody>
		</tgroup>
		</informaltable>
	      </para>
	  </formalpara>
	</example>
      </refsect1>
    </refentry>