| <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> |
