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Based on kernel version 3.13. Page generated on 2014-01-20 22:02 EST.

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
10	chroma resolution, also known as YUV 4:2:2. One luminance and one
11	chrominance 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.
18	The three components are separated into two sub-images or planes. The
19	Y plane is first. The Y plane has one byte per pixel. For
20	<constant>V4L2_PIX_FMT_NV16</constant>, a combined CbCr plane
21	immediately follows the Y plane in memory.  The CbCr plane is the same
22	width and height, in bytes, as the Y plane (and of the image).
23	Each CbCr pair belongs to two pixels. For example,
24	Cb<subscript>0</subscript>/Cr<subscript>0</subscript> belongs to
25	Y'<subscript>00</subscript>, Y'<subscript>01</subscript>.
26	<constant>V4L2_PIX_FMT_NV61</constant> is the same except the Cb and
27	Cr 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
30	CbCr plane has as many pad bytes after its rows.</para>
31	
32		<example>
33		  <title><constant>V4L2_PIX_FMT_NV16</constant> 4 &times; 4
34	pixel 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>
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