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

1	    <refentry id="V4L2-PIX-FMT-YUV422P">
2	      <refmeta>
3		<refentrytitle>V4L2_PIX_FMT_YUV422P ('422P')</refentrytitle>
4		&manvol;
5	      </refmeta>
6	      <refnamediv>
7		<refname><constant>V4L2_PIX_FMT_YUV422P</constant></refname>
8		<refpurpose>Format with &frac12; horizontal chroma resolution,
9	also known as YUV 4:2:2. Planar layout as opposed to
10	<constant>V4L2_PIX_FMT_YUYV</constant></refpurpose>
11	      </refnamediv>
12	      <refsect1>
13		<title>Description</title>
14	
15		<para>This format is not commonly used. This is a planar
16	version of the YUYV format. The three components are separated into
17	three sub-images or planes. The Y plane is first. The Y plane has one
18	byte per pixel. The Cb plane immediately follows the Y plane in
19	memory. The Cb plane is half the width of the Y plane (and of the
20	image). Each Cb belongs to two pixels. For example,
21	Cb<subscript>0</subscript> belongs to Y'<subscript>00</subscript>,
22	Y'<subscript>01</subscript>. Following the Cb plane is the Cr plane,
23	just like the Cb plane.</para>
24	
25		<para>If the Y plane has pad bytes after each row, then the Cr
26	and Cb planes have half as many pad bytes after their rows. In other
27	words, two Cx rows (including padding) is exactly as long as one Y row
28	(including padding).</para>
29	
30		<example>
31		  <title><constant>V4L2_PIX_FMT_YUV422P</constant> 4 &times; 4
32	pixel image</title>
33	
34		  <formalpara>
35		    <title>Byte Order.</title>
36		    <para>Each cell is one byte.
37			<informaltable frame="none">
38			<tgroup cols="5" align="center">
39			  <colspec align="left" colwidth="2*" />
40			  <tbody valign="top">
41			    <row>
42			      <entry>start&nbsp;+&nbsp;0:</entry>
43			      <entry>Y'<subscript>00</subscript></entry>
44			      <entry>Y'<subscript>01</subscript></entry>
45			      <entry>Y'<subscript>02</subscript></entry>
46			      <entry>Y'<subscript>03</subscript></entry>
47			    </row>
48			    <row>
49			      <entry>start&nbsp;+&nbsp;4:</entry>
50			      <entry>Y'<subscript>10</subscript></entry>
51			      <entry>Y'<subscript>11</subscript></entry>
52			      <entry>Y'<subscript>12</subscript></entry>
53			      <entry>Y'<subscript>13</subscript></entry>
54			    </row>
55			    <row>
56			      <entry>start&nbsp;+&nbsp;8:</entry>
57			      <entry>Y'<subscript>20</subscript></entry>
58			      <entry>Y'<subscript>21</subscript></entry>
59			      <entry>Y'<subscript>22</subscript></entry>
60			      <entry>Y'<subscript>23</subscript></entry>
61			    </row>
62			    <row>
63			      <entry>start&nbsp;+&nbsp;12:</entry>
64			      <entry>Y'<subscript>30</subscript></entry>
65			      <entry>Y'<subscript>31</subscript></entry>
66			      <entry>Y'<subscript>32</subscript></entry>
67			      <entry>Y'<subscript>33</subscript></entry>
68			    </row>
69			    <row>
70			      <entry>start&nbsp;+&nbsp;16:</entry>
71			      <entry>Cb<subscript>00</subscript></entry>
72			      <entry>Cb<subscript>01</subscript></entry>
73			    </row>
74			    <row>
75			      <entry>start&nbsp;+&nbsp;18:</entry>
76			      <entry>Cb<subscript>10</subscript></entry>
77			      <entry>Cb<subscript>11</subscript></entry>
78			    </row>
79			    <row>
80			      <entry>start&nbsp;+&nbsp;20:</entry>
81			      <entry>Cb<subscript>20</subscript></entry>
82			      <entry>Cb<subscript>21</subscript></entry>
83			    </row>
84			    <row>
85			      <entry>start&nbsp;+&nbsp;22:</entry>
86			      <entry>Cb<subscript>30</subscript></entry>
87			      <entry>Cb<subscript>31</subscript></entry>
88			    </row>
89			    <row>
90			      <entry>start&nbsp;+&nbsp;24:</entry>
91			      <entry>Cr<subscript>00</subscript></entry>
92			      <entry>Cr<subscript>01</subscript></entry>
93			    </row>
94			    <row>
95			      <entry>start&nbsp;+&nbsp;26:</entry>
96			      <entry>Cr<subscript>10</subscript></entry>
97			      <entry>Cr<subscript>11</subscript></entry>
98			    </row>
99			    <row>
100			      <entry>start&nbsp;+&nbsp;28:</entry>
101			      <entry>Cr<subscript>20</subscript></entry>
102			      <entry>Cr<subscript>21</subscript></entry>
103			    </row>
104			    <row>
105			      <entry>start&nbsp;+&nbsp;30:</entry>
106			      <entry>Cr<subscript>30</subscript></entry>
107			      <entry>Cr<subscript>31</subscript></entry>
108			    </row>
109			  </tbody>
110			</tgroup>
111			</informaltable>
112		      </para>
113		  </formalpara>
114	
115		  <formalpara>
116		    <title>Color Sample Location.</title>
117		    <para>
118			<informaltable frame="none">
119			<tgroup cols="7" align="center">
120			  <tbody valign="top">
121			    <row>
122			      <entry></entry>
123			      <entry>0</entry><entry></entry><entry>1</entry><entry></entry>
124			      <entry>2</entry><entry></entry><entry>3</entry>
125			    </row>
126			    <row>
127			      <entry>0</entry>
128			      <entry>Y</entry><entry>C</entry><entry>Y</entry><entry></entry>
129			      <entry>Y</entry><entry>C</entry><entry>Y</entry>
130			    </row>
131			    <row>
132			      <entry>1</entry>
133			      <entry>Y</entry><entry>C</entry><entry>Y</entry><entry></entry>
134			      <entry>Y</entry><entry>C</entry><entry>Y</entry>
135			    </row>
136			    <row>
137			      <entry>2</entry>
138			      <entry>Y</entry><entry>C</entry><entry>Y</entry><entry></entry>
139			      <entry>Y</entry><entry>C</entry><entry>Y</entry>
140			    </row>
141			    <row>
142			      <entry>3</entry>
143			      <entry>Y</entry><entry>C</entry><entry>Y</entry><entry></entry>
144			      <entry>Y</entry><entry>C</entry><entry>Y</entry>
145			    </row>
146			  </tbody>
147			</tgroup>
148			</informaltable>
149		      </para>
150		  </formalpara>
151		</example>
152	      </refsect1>
153	    </refentry>
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