Documentation/DocBook/v4l/pixfmt-y41p.xml

   1     <refentry id="V4L2-PIX-FMT-Y41P">
   2       <refmeta>
   3         <refentrytitle>V4L2_PIX_FMT_Y41P ('Y41P')</refentrytitle>
   4         &manvol;
   5       </refmeta>
   6       <refnamediv>
   7         <refname><constant>V4L2_PIX_FMT_Y41P</constant></refname>
   8         <refpurpose>Format with &frac14; horizontal chroma
   9 resolution, also known as YUV 4:1:1</refpurpose>
  10       </refnamediv>
  11       <refsect1>
  12         <title>Description</title>
  13
  14         <para>In this format each 12 bytes is eight pixels. In the
  15 twelve bytes are two CbCr pairs and eight Y's. The first CbCr pair
  16 goes with the first four Y's, and the second CbCr pair goes with the
  17 other four Y's. The Cb and Cr components have one fourth the
  18 horizontal resolution of the Y component.</para>
  19
  20         <para>Do not confuse this format with <link
  21 linkend="V4L2-PIX-FMT-YUV411P"><constant>V4L2_PIX_FMT_YUV411P</constant></link>.
  22 Y41P is derived from "YUV 4:1:1 <emphasis>packed</emphasis>", while
  23 YUV411P stands for "YUV 4:1:1 <emphasis>planar</emphasis>".</para>
  24
  25         <example>
  26           <title><constant>V4L2_PIX_FMT_Y41P</constant> 8 &times; 4
  27 pixel image</title>
  28
  29           <formalpara>
  30             <title>Byte Order</title>
  31             <para>Each cell is one byte.
  32                 <informaltable frame="none">
  33                 <tgroup cols="13" align="center">
  34                   <colspec align="left" colwidth="2*" />
  35                   <tbody valign="top">
  36                     <row>
  37                       <entry>start&nbsp;+&nbsp;0:</entry>
  38                       <entry>Cb<subscript>00</subscript></entry>
  39                       <entry>Y'<subscript>00</subscript></entry>
  40                       <entry>Cr<subscript>00</subscript></entry>
  41                       <entry>Y'<subscript>01</subscript></entry>
  42                       <entry>Cb<subscript>01</subscript></entry>
  43                       <entry>Y'<subscript>02</subscript></entry>
  44                       <entry>Cr<subscript>01</subscript></entry>
  45                       <entry>Y'<subscript>03</subscript></entry>
  46                       <entry>Y'<subscript>04</subscript></entry>
  47                       <entry>Y'<subscript>05</subscript></entry>
  48                       <entry>Y'<subscript>06</subscript></entry>
  49                       <entry>Y'<subscript>07</subscript></entry>
  50                     </row>
  51                     <row>
  52                       <entry>start&nbsp;+&nbsp;12:</entry>
  53                       <entry>Cb<subscript>10</subscript></entry>
  54                       <entry>Y'<subscript>10</subscript></entry>
  55                       <entry>Cr<subscript>10</subscript></entry>
  56                       <entry>Y'<subscript>11</subscript></entry>
  57                       <entry>Cb<subscript>11</subscript></entry>
  58                       <entry>Y'<subscript>12</subscript></entry>
  59                       <entry>Cr<subscript>11</subscript></entry>
  60                       <entry>Y'<subscript>13</subscript></entry>
  61                       <entry>Y'<subscript>14</subscript></entry>
  62                       <entry>Y'<subscript>15</subscript></entry>
  63                       <entry>Y'<subscript>16</subscript></entry>
  64                       <entry>Y'<subscript>17</subscript></entry>
  65                     </row>
  66                     <row>
  67                       <entry>start&nbsp;+&nbsp;24:</entry>
  68                       <entry>Cb<subscript>20</subscript></entry>
  69                       <entry>Y'<subscript>20</subscript></entry>
  70                       <entry>Cr<subscript>20</subscript></entry>
  71                       <entry>Y'<subscript>21</subscript></entry>
  72                       <entry>Cb<subscript>21</subscript></entry>
  73                       <entry>Y'<subscript>22</subscript></entry>
  74                       <entry>Cr<subscript>21</subscript></entry>
  75                       <entry>Y'<subscript>23</subscript></entry>
  76                       <entry>Y'<subscript>24</subscript></entry>
  77                       <entry>Y'<subscript>25</subscript></entry>
  78                       <entry>Y'<subscript>26</subscript></entry>
  79                       <entry>Y'<subscript>27</subscript></entry>
  80                     </row>
  81                     <row>
  82                       <entry>start&nbsp;+&nbsp;36:</entry>
  83                       <entry>Cb<subscript>30</subscript></entry>
  84                       <entry>Y'<subscript>30</subscript></entry>
  85                       <entry>Cr<subscript>30</subscript></entry>
  86                       <entry>Y'<subscript>31</subscript></entry>
  87                       <entry>Cb<subscript>31</subscript></entry>
  88                       <entry>Y'<subscript>32</subscript></entry>
  89                       <entry>Cr<subscript>31</subscript></entry>
  90                       <entry>Y'<subscript>33</subscript></entry>
  91                       <entry>Y'<subscript>34</subscript></entry>
  92                       <entry>Y'<subscript>35</subscript></entry>
  93                       <entry>Y'<subscript>36</subscript></entry>
  94                       <entry>Y'<subscript>37</subscript></entry>
  95                     </row>
  96                   </tbody>
  97                 </tgroup>
  98               </informaltable></para>
  99           </formalpara>
 100
 101           <formalpara>
 102             <title>Color Sample Location.</title>
 103             <para>
 104                 <informaltable frame="none">
 105                 <tgroup cols="15" align="center">
 106                   <tbody valign="top">
 107                     <row>
 108                       <entry></entry>
 109                       <entry>0</entry><entry></entry><entry>1</entry><entry></entry>
 110                       <entry>2</entry><entry></entry><entry>3</entry><entry></entry>
 111                       <entry>4</entry><entry></entry><entry>5</entry><entry></entry>
 112                       <entry>6</entry><entry></entry><entry>7</entry>
 113                     </row>
 114                     <row>
 115                       <entry>0</entry>
 116                       <entry>Y</entry><entry></entry><entry>Y</entry><entry>C</entry>
 117                       <entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
 118                       <entry>Y</entry><entry></entry><entry>Y</entry><entry>C</entry>
 119                       <entry>Y</entry><entry></entry><entry>Y</entry>
 120                     </row>
 121                     <row>
 122                       <entry>1</entry>
 123                       <entry>Y</entry><entry></entry><entry>Y</entry><entry>C</entry>
 124                       <entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
 125                       <entry>Y</entry><entry></entry><entry>Y</entry><entry>C</entry>
 126                       <entry>Y</entry><entry></entry><entry>Y</entry>
 127                     </row>
 128                     <row>
 129                       <entry>2</entry>
 130                       <entry>Y</entry><entry></entry><entry>Y</entry><entry>C</entry>
 131                       <entry>Y</entry><entry></entry><entry>Y</entry><entry></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><entry></entry>
 139                       <entry>Y</entry><entry></entry><entry>Y</entry><entry>C</entry>
 140                       <entry>Y</entry><entry></entry><entry>Y</entry>
 141                     </row>
 142                   </tbody>
 143                 </tgroup>
 144                 </informaltable>
 145               </para>
 146           </formalpara>
 147         </example>
 148       </refsect1>
 149     </refentry>
 150
 151   <!--
 152 Local Variables:
 153 mode: sgml
 154 sgml-parent-document: "pixfmt.sgml"
 155 indent-tabs-mode: nil
 156 End:
 157   -->