CooCenter-System-kernel/Documentation/DocBook/media/v4l/pixfmt-nv16m.xml

    <refentry>
      <refmeta>
	<refentrytitle>V4L2_PIX_FMT_NV16M ('NM16'), V4L2_PIX_FMT_NV61M ('NM61')</refentrytitle>
	&manvol;
      </refmeta>
      <refnamediv>
	<refname id="V4L2-PIX-FMT-NV16M"><constant>V4L2_PIX_FMT_NV16M</constant></refname>
	<refname id="V4L2-PIX-FMT-NV61M"><constant>V4L2_PIX_FMT_NV61M</constant></refname>
	<refpurpose>Variation of <constant>V4L2_PIX_FMT_NV16</constant> and <constant>V4L2_PIX_FMT_NV61</constant> with planes
	  non contiguous in memory. </refpurpose>
      </refnamediv>
      <refsect1>
	<title>Description</title>

	<para>This is a multi-planar, two-plane version of the YUV 4:2:2 format.
The three components are separated into two sub-images or planes.
<constant>V4L2_PIX_FMT_NV16M</constant> differs from <constant>V4L2_PIX_FMT_NV16
</constant> in that the two planes are non-contiguous in memory, i.e. the chroma
plane does not necessarily immediately follow the luma plane.
The luminance data occupies the first plane. The Y plane has one byte per pixel.
In the second plane there is chrominance data with alternating chroma samples.
The CbCr plane is the same width and height, in bytes, as the Y plane.
Each CbCr pair belongs to two pixels. For example,
Cb<subscript>0</subscript>/Cr<subscript>0</subscript> belongs to
Y'<subscript>00</subscript>, Y'<subscript>01</subscript>.
<constant>V4L2_PIX_FMT_NV61M</constant> is the same as <constant>V4L2_PIX_FMT_NV16M</constant>
except the Cb and Cr bytes are swapped, the CrCb plane starts with a Cr byte.</para>

	<para><constant>V4L2_PIX_FMT_NV16M</constant> and
<constant>V4L2_PIX_FMT_NV61M</constant> are intended to be used only in drivers
and applications that support the multi-planar API, described in
<xref linkend="planar-apis"/>. </para>

	<example>
	  <title><constant>V4L2_PIX_FMT_NV16M</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>start0&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>start0&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>start0&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>start0&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></entry>
		    </row>
		    <row>
		      <entry>start1&nbsp;+&nbsp;0:</entry>
		      <entry>Cb<subscript>00</subscript></entry>
		      <entry>Cr<subscript>00</subscript></entry>
		      <entry>Cb<subscript>02</subscript></entry>
		      <entry>Cr<subscript>02</subscript></entry>
		    </row>
		    <row>
		      <entry>start1&nbsp;+&nbsp;4:</entry>
		      <entry>Cb<subscript>10</subscript></entry>
		      <entry>Cr<subscript>10</subscript></entry>
		      <entry>Cb<subscript>12</subscript></entry>
		      <entry>Cr<subscript>12</subscript></entry>
		    </row>
		    <row>
		      <entry>start1&nbsp;+&nbsp;8:</entry>
		      <entry>Cb<subscript>20</subscript></entry>
		      <entry>Cr<subscript>20</subscript></entry>
		      <entry>Cb<subscript>22</subscript></entry>
		      <entry>Cr<subscript>22</subscript></entry>
		    </row>
		    <row>
		      <entry>start1&nbsp;+&nbsp;12:</entry>
		      <entry>Cb<subscript>30</subscript></entry>
		      <entry>Cr<subscript>30</subscript></entry>
		      <entry>Cb<subscript>32</subscript></entry>
		      <entry>Cr<subscript>32</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>
		      <entry></entry><entry>C</entry><entry></entry><entry></entry>
		      <entry></entry><entry>C</entry><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>C</entry><entry></entry><entry></entry>
		      <entry></entry><entry>C</entry><entry></entry>
		    </row>
		    <row>
		      <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>
		      <entry></entry><entry>C</entry><entry></entry><entry></entry>
		      <entry></entry><entry>C</entry><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>
		    <row>
		      <entry></entry>
		      <entry></entry><entry>C</entry><entry></entry><entry></entry>
		      <entry></entry><entry>C</entry><entry></entry>
		    </row>
		  </tbody>
		</tgroup>
		</informaltable>
	      </para>
	  </formalpara>
	</example>
      </refsect1>
    </refentry>