Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab...
[linux-2.6.git] / Documentation / DocBook / media / v4l / pixfmt-yuv410.xml
1     <refentry>
2       <refmeta>
3         <refentrytitle>V4L2_PIX_FMT_YVU410 ('YVU9'), V4L2_PIX_FMT_YUV410 ('YUV9')</refentrytitle>
4         &manvol;
5       </refmeta>
6       <refnamediv>
7         <refname id="V4L2-PIX-FMT-YVU410"><constant>V4L2_PIX_FMT_YVU410</constant></refname>
8         <refname id="V4L2-PIX-FMT-YUV410"><constant>V4L2_PIX_FMT_YUV410</constant></refname>
9         <refpurpose>Planar formats with &frac14; horizontal and
10 vertical chroma resolution, also known as YUV 4:1:0</refpurpose>
11       </refnamediv>
12       <refsect1>
13         <title>Description</title>
14
15         <para>These are planar formats, as opposed to a packed format.
16 The three components are separated into three sub-images or planes.
17 The Y plane is first. The Y plane has one byte per pixel. For
18 <constant>V4L2_PIX_FMT_YVU410</constant>, the Cr plane immediately
19 follows the Y plane in memory. The Cr plane is &frac14; the width and
20 &frac14; the height of the Y plane (and of the image). Each Cr belongs
21 to 16 pixels, a four-by-four square of the image. Following the Cr
22 plane is the Cb plane, just like the Cr plane.
23 <constant>V4L2_PIX_FMT_YUV410</constant> is the same, except the Cb
24 plane comes first, then the Cr plane.</para>
25
26         <para>If the Y plane has pad bytes after each row, then the Cr
27 and Cb planes have &frac14; as many pad bytes after their rows. In
28 other words, four Cx rows (including padding) are exactly as long as
29 one Y row (including padding).</para>
30
31         <example>
32           <title><constant>V4L2_PIX_FMT_YVU410</constant> 4 &times; 4
33 pixel image</title>
34
35           <formalpara>
36             <title>Byte Order.</title>
37             <para>Each cell is one byte.
38                 <informaltable frame="none">
39                 <tgroup cols="5" align="center">
40                   <colspec align="left" colwidth="2*" />
41                   <tbody valign="top">
42                     <row>
43                       <entry>start&nbsp;+&nbsp;0:</entry>
44                       <entry>Y'<subscript>00</subscript></entry>
45                       <entry>Y'<subscript>01</subscript></entry>
46                       <entry>Y'<subscript>02</subscript></entry>
47                       <entry>Y'<subscript>03</subscript></entry>
48                     </row>
49                     <row>
50                       <entry>start&nbsp;+&nbsp;4:</entry>
51                       <entry>Y'<subscript>10</subscript></entry>
52                       <entry>Y'<subscript>11</subscript></entry>
53                       <entry>Y'<subscript>12</subscript></entry>
54                       <entry>Y'<subscript>13</subscript></entry>
55                     </row>
56                     <row>
57                       <entry>start&nbsp;+&nbsp;8:</entry>
58                       <entry>Y'<subscript>20</subscript></entry>
59                       <entry>Y'<subscript>21</subscript></entry>
60                       <entry>Y'<subscript>22</subscript></entry>
61                       <entry>Y'<subscript>23</subscript></entry>
62                     </row>
63                     <row>
64                       <entry>start&nbsp;+&nbsp;12:</entry>
65                       <entry>Y'<subscript>30</subscript></entry>
66                       <entry>Y'<subscript>31</subscript></entry>
67                       <entry>Y'<subscript>32</subscript></entry>
68                       <entry>Y'<subscript>33</subscript></entry>
69                     </row>
70                     <row>
71                       <entry>start&nbsp;+&nbsp;16:</entry>
72                       <entry>Cr<subscript>00</subscript></entry>
73                     </row>
74                     <row>
75                       <entry>start&nbsp;+&nbsp;17:</entry>
76                       <entry>Cb<subscript>00</subscript></entry>
77                     </row>
78                   </tbody>
79                 </tgroup>
80                 </informaltable>
81               </para>
82           </formalpara>
83
84           <formalpara>
85             <title>Color Sample Location.</title>
86             <para>
87                 <informaltable frame="none">
88                 <tgroup cols="7" align="center">
89                   <tbody valign="top">
90                     <row>
91                       <entry></entry>
92                       <entry>0</entry><entry></entry><entry>1</entry><entry></entry>
93                       <entry>2</entry><entry></entry><entry>3</entry>
94                     </row>
95                     <row>
96                       <entry>0</entry>
97                       <entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
98                       <entry>Y</entry><entry></entry><entry>Y</entry>
99                     </row>
100                     <row>
101                       <entry></entry>
102                     </row>
103                     <row>
104                       <entry>1</entry>
105                       <entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
106                       <entry>Y</entry><entry></entry><entry>Y</entry>
107                     </row>
108                     <row>
109                       <entry></entry>
110                       <entry></entry><entry></entry><entry></entry><entry>C</entry>
111                       <entry></entry><entry></entry><entry></entry>
112                     </row>
113                     <row>
114                       <entry>2</entry>
115                       <entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
116                       <entry>Y</entry><entry></entry><entry>Y</entry>
117                     </row>
118                     <row>
119                       <entry></entry>
120                     </row>
121                     <row>
122                       <entry>3</entry>
123                       <entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
124                       <entry>Y</entry><entry></entry><entry>Y</entry>
125                     </row>
126                   </tbody>
127                 </tgroup>
128                 </informaltable>
129               </para>
130           </formalpara>
131         </example>
132       </refsect1>
133     </refentry>