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1    <refentry>
2      <refmeta>
3	<refentrytitle>V4L2_PIX_FMT_NV16 ('NV16'), V4L2_PIX_FMT_NV61 ('NV61')</refentrytitle>
4	&manvol;
5      </refmeta>
6      <refnamediv>
7	<refname id="V4L2-PIX-FMT-NV16"><constant>V4L2_PIX_FMT_NV16</constant></refname>
8	<refname id="V4L2-PIX-FMT-NV61"><constant>V4L2_PIX_FMT_NV61</constant></refname>
9	<refpurpose>Formats with &frac12; horizontal
10chroma resolution, also known as YUV 4:2:2. One luminance and one
11chrominance plane with alternating chroma samples as opposed to
12<constant>V4L2_PIX_FMT_YVU420</constant></refpurpose>
13      </refnamediv>
14      <refsect1>
15	<title>Description</title>
16
17	<para>These are two-plane versions of the YUV 4:2:2 format.
18The three components are separated into two sub-images or planes. The
19Y plane is first. The Y plane has one byte per pixel. For
20<constant>V4L2_PIX_FMT_NV16</constant>, a combined CbCr plane
21immediately follows the Y plane in memory.  The CbCr plane is the same
22width and height, in bytes, as the Y plane (and of the image).
23Each CbCr pair belongs to two pixels. For example,
24Cb<subscript>0</subscript>/Cr<subscript>0</subscript> belongs to
25Y'<subscript>00</subscript>, Y'<subscript>01</subscript>.
26<constant>V4L2_PIX_FMT_NV61</constant> is the same except the Cb and
27Cr bytes are swapped, the CrCb plane starts with a Cr byte.</para>
28
29	<para>If the Y plane has pad bytes after each row, then the
30CbCr plane has as many pad bytes after its rows.</para>
31
32	<example>
33	  <title><constant>V4L2_PIX_FMT_NV16</constant> 4 &times; 4
34pixel image</title>
35
36	  <formalpara>
37	    <title>Byte Order.</title>
38	    <para>Each cell is one byte.
39		<informaltable frame="none">
40		<tgroup cols="5" align="center">
41		  <colspec align="left" colwidth="2*" />
42		  <tbody valign="top">
43		    <row>
44		      <entry>start&nbsp;+&nbsp;0:</entry>
45		      <entry>Y'<subscript>00</subscript></entry>
46		      <entry>Y'<subscript>01</subscript></entry>
47		      <entry>Y'<subscript>02</subscript></entry>
48		      <entry>Y'<subscript>03</subscript></entry>
49		    </row>
50		    <row>
51		      <entry>start&nbsp;+&nbsp;4:</entry>
52		      <entry>Y'<subscript>10</subscript></entry>
53		      <entry>Y'<subscript>11</subscript></entry>
54		      <entry>Y'<subscript>12</subscript></entry>
55		      <entry>Y'<subscript>13</subscript></entry>
56		    </row>
57		    <row>
58		      <entry>start&nbsp;+&nbsp;8:</entry>
59		      <entry>Y'<subscript>20</subscript></entry>
60		      <entry>Y'<subscript>21</subscript></entry>
61		      <entry>Y'<subscript>22</subscript></entry>
62		      <entry>Y'<subscript>23</subscript></entry>
63		    </row>
64		    <row>
65		      <entry>start&nbsp;+&nbsp;12:</entry>
66		      <entry>Y'<subscript>30</subscript></entry>
67		      <entry>Y'<subscript>31</subscript></entry>
68		      <entry>Y'<subscript>32</subscript></entry>
69		      <entry>Y'<subscript>33</subscript></entry>
70		    </row>
71		    <row>
72		      <entry>start&nbsp;+&nbsp;16:</entry>
73		      <entry>Cb<subscript>00</subscript></entry>
74		      <entry>Cr<subscript>00</subscript></entry>
75		      <entry>Cb<subscript>01</subscript></entry>
76		      <entry>Cr<subscript>01</subscript></entry>
77		    </row>
78		    <row>
79		      <entry>start&nbsp;+&nbsp;20:</entry>
80		      <entry>Cb<subscript>10</subscript></entry>
81		      <entry>Cr<subscript>10</subscript></entry>
82		      <entry>Cb<subscript>11</subscript></entry>
83		      <entry>Cr<subscript>11</subscript></entry>
84		    </row>
85		    <row>
86		      <entry>start&nbsp;+&nbsp;24:</entry>
87		      <entry>Cb<subscript>20</subscript></entry>
88		      <entry>Cr<subscript>20</subscript></entry>
89		      <entry>Cb<subscript>21</subscript></entry>
90		      <entry>Cr<subscript>21</subscript></entry>
91		    </row>
92		    <row>
93		      <entry>start&nbsp;+&nbsp;28:</entry>
94		      <entry>Cb<subscript>30</subscript></entry>
95		      <entry>Cr<subscript>30</subscript></entry>
96		      <entry>Cb<subscript>31</subscript></entry>
97		      <entry>Cr<subscript>31</subscript></entry>
98		    </row>
99		  </tbody>
100		</tgroup>
101		</informaltable>
102	      </para>
103	  </formalpara>
104
105	  <formalpara>
106	    <title>Color Sample Location.</title>
107	    <para>
108		<informaltable frame="none">
109		<tgroup cols="7" align="center">
110		  <tbody valign="top">
111		    <row>
112		      <entry></entry>
113		      <entry>0</entry><entry></entry><entry>1</entry><entry></entry>
114		      <entry>2</entry><entry></entry><entry>3</entry>
115		    </row>
116		    <row>
117		      <entry>0</entry>
118		      <entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
119		      <entry>Y</entry><entry></entry><entry>Y</entry>
120		    </row>
121		    <row>
122		      <entry></entry>
123		      <entry></entry><entry>C</entry><entry></entry><entry></entry>
124		      <entry></entry><entry>C</entry><entry></entry>
125		    </row>
126		    <row>
127		      <entry>1</entry>
128		      <entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
129		      <entry>Y</entry><entry></entry><entry>Y</entry>
130		    </row>
131		    <row>
132		      <entry></entry>
133		      <entry></entry><entry>C</entry><entry></entry><entry></entry>
134		      <entry></entry><entry>C</entry><entry></entry>
135		    </row>
136		    <row>
137		      <entry></entry>
138		    </row>
139		    <row>
140		      <entry>2</entry>
141		      <entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
142		      <entry>Y</entry><entry></entry><entry>Y</entry>
143		    </row>
144		    <row>
145		      <entry></entry>
146		      <entry></entry><entry>C</entry><entry></entry><entry></entry>
147		      <entry></entry><entry>C</entry><entry></entry>
148		    </row>
149		    <row>
150		      <entry>3</entry>
151		      <entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
152		      <entry>Y</entry><entry></entry><entry>Y</entry>
153		    </row>
154		    <row>
155		      <entry></entry>
156		      <entry></entry><entry>C</entry><entry></entry><entry></entry>
157		      <entry></entry><entry>C</entry><entry></entry>
158		    </row>
159		  </tbody>
160		</tgroup>
161		</informaltable>
162	      </para>
163	  </formalpara>
164	</example>
165      </refsect1>
166    </refentry>
167
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175