Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6.git] / Documentation / DocBook / v4l / pixfmt-yuv411p.xml
1     <refentry id="V4L2-PIX-FMT-YUV411P">
2       <refmeta>
3         <refentrytitle>V4L2_PIX_FMT_YUV411P ('411P')</refentrytitle>
4         &manvol;
5       </refmeta>
6       <refnamediv>
7         <refname><constant>V4L2_PIX_FMT_YUV411P</constant></refname>
8         <refpurpose>Format with &frac14; horizontal chroma resolution,
9 also known as YUV 4:1:1. Planar layout as opposed to
10 <constant>V4L2_PIX_FMT_Y41P</constant></refpurpose>
11       </refnamediv>
12       <refsect1>
13         <title>Description</title>
14
15         <para>This format is not commonly used. This is a planar
16 format similar to the 4:2:2 planar format except with half as many
17 chroma. The three components are separated into three sub-images or
18 planes. The Y plane is first. The Y plane has one byte per pixel. The
19 Cb plane immediately follows the Y plane in memory. The Cb plane is
20 &frac14; the width of the Y plane (and of the image). Each Cb belongs
21 to 4 pixels all on the same row. For example,
22 Cb<subscript>0</subscript> belongs to Y'<subscript>00</subscript>,
23 Y'<subscript>01</subscript>, Y'<subscript>02</subscript> and
24 Y'<subscript>03</subscript>. Following the Cb plane is the Cr plane,
25 just like the Cb plane.</para>
26
27         <para>If the Y plane has pad bytes after each row, then the Cr
28 and Cb planes have &frac14; as many pad bytes after their rows. In
29 other words, four C x rows (including padding) is exactly as long as
30 one Y row (including padding).</para>
31
32         <example>
33           <title><constant>V4L2_PIX_FMT_YUV411P</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                     </row>
75                     <row>
76                       <entry>start&nbsp;+&nbsp;17:</entry>
77                       <entry>Cb<subscript>10</subscript></entry>
78                     </row>
79                     <row>
80                       <entry>start&nbsp;+&nbsp;18:</entry>
81                       <entry>Cb<subscript>20</subscript></entry>
82                     </row>
83                     <row>
84                       <entry>start&nbsp;+&nbsp;19:</entry>
85                       <entry>Cb<subscript>30</subscript></entry>
86                     </row>
87                     <row>
88                       <entry>start&nbsp;+&nbsp;20:</entry>
89                       <entry>Cr<subscript>00</subscript></entry>
90                     </row>
91                     <row>
92                       <entry>start&nbsp;+&nbsp;21:</entry>
93                       <entry>Cr<subscript>10</subscript></entry>
94                     </row>
95                     <row>
96                       <entry>start&nbsp;+&nbsp;22:</entry>
97                       <entry>Cr<subscript>20</subscript></entry>
98                     </row>
99                     <row>
100                       <entry>start&nbsp;+&nbsp;23:</entry>
101                       <entry>Cr<subscript>30</subscript></entry>
102                     </row>
103                   </tbody>
104                 </tgroup>
105                 </informaltable>
106               </para>
107           </formalpara>
108
109           <formalpara>
110             <title>Color Sample Location.</title>
111             <para>
112                 <informaltable frame="none">
113                 <tgroup cols="7" align="center">
114                   <tbody valign="top">
115                     <row>
116                       <entry></entry>
117                       <entry>0</entry><entry></entry><entry>1</entry><entry></entry>
118                       <entry>2</entry><entry></entry><entry>3</entry>
119                     </row>
120                     <row>
121                       <entry>0</entry>
122                       <entry>Y</entry><entry></entry><entry>Y</entry><entry>C</entry>
123                       <entry>Y</entry><entry></entry><entry>Y</entry>
124                     </row>
125                     <row>
126                       <entry>1</entry>
127                       <entry>Y</entry><entry></entry><entry>Y</entry><entry>C</entry>
128                       <entry>Y</entry><entry></entry><entry>Y</entry>
129                     </row>
130                     <row>
131                       <entry>2</entry>
132                       <entry>Y</entry><entry></entry><entry>Y</entry><entry>C</entry>
133                       <entry>Y</entry><entry></entry><entry>Y</entry>
134                     </row>
135                     <row>
136                       <entry>3</entry>
137                       <entry>Y</entry><entry></entry><entry>Y</entry><entry>C</entry>
138                       <entry>Y</entry><entry></entry><entry>Y</entry>
139                     </row>
140                   </tbody>
141                 </tgroup>
142                 </informaltable>
143               </para>
144           </formalpara>
145         </example>
146       </refsect1>
147     </refentry>
148
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