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- <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 × 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 + 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 + 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 + 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 + 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 + 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 + 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 + 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 + 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>
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