Mauro Carvalho Chehab | 8e080c2 | 2009-09-13 22:16:04 -0300 | [diff] [blame] | 1 | <refentry id="V4L2-PIX-FMT-YUYV"> |
| 2 | <refmeta> |
| 3 | <refentrytitle>V4L2_PIX_FMT_YUYV ('YUYV')</refentrytitle> |
| 4 | &manvol; |
| 5 | </refmeta> |
| 6 | <refnamediv> |
| 7 | <refname><constant>V4L2_PIX_FMT_YUYV</constant></refname> |
| 8 | <refpurpose>Packed format with ½ horizontal chroma |
| 9 | resolution, also known as YUV 4:2:2</refpurpose> |
| 10 | </refnamediv> |
| 11 | <refsect1> |
| 12 | <title>Description</title> |
| 13 | |
| 14 | <para>In this format each four bytes is two pixels. Each four |
| 15 | bytes is two Y's, a Cb and a Cr. Each Y goes to one of the pixels, and |
| 16 | the Cb and Cr belong to both pixels. As you can see, the Cr and Cb |
| 17 | components have half the horizontal resolution of the Y component. |
| 18 | <constant>V4L2_PIX_FMT_YUYV </constant> is known in the Windows |
| 19 | environment as YUY2.</para> |
| 20 | |
| 21 | <example> |
| 22 | <title><constant>V4L2_PIX_FMT_YUYV</constant> 4 × 4 |
| 23 | pixel image</title> |
| 24 | |
| 25 | <formalpara> |
| 26 | <title>Byte Order.</title> |
| 27 | <para>Each cell is one byte. |
| 28 | <informaltable frame="none"> |
| 29 | <tgroup cols="9" align="center"> |
| 30 | <colspec align="left" colwidth="2*" /> |
| 31 | <tbody valign="top"> |
| 32 | <row> |
| 33 | <entry>start + 0:</entry> |
| 34 | <entry>Y'<subscript>00</subscript></entry> |
| 35 | <entry>Cb<subscript>00</subscript></entry> |
| 36 | <entry>Y'<subscript>01</subscript></entry> |
| 37 | <entry>Cr<subscript>00</subscript></entry> |
| 38 | <entry>Y'<subscript>02</subscript></entry> |
| 39 | <entry>Cb<subscript>01</subscript></entry> |
| 40 | <entry>Y'<subscript>03</subscript></entry> |
| 41 | <entry>Cr<subscript>01</subscript></entry> |
| 42 | </row> |
| 43 | <row> |
| 44 | <entry>start + 8:</entry> |
| 45 | <entry>Y'<subscript>10</subscript></entry> |
| 46 | <entry>Cb<subscript>10</subscript></entry> |
| 47 | <entry>Y'<subscript>11</subscript></entry> |
| 48 | <entry>Cr<subscript>10</subscript></entry> |
| 49 | <entry>Y'<subscript>12</subscript></entry> |
| 50 | <entry>Cb<subscript>11</subscript></entry> |
| 51 | <entry>Y'<subscript>13</subscript></entry> |
| 52 | <entry>Cr<subscript>11</subscript></entry> |
| 53 | </row> |
| 54 | <row> |
| 55 | <entry>start + 16:</entry> |
| 56 | <entry>Y'<subscript>20</subscript></entry> |
| 57 | <entry>Cb<subscript>20</subscript></entry> |
| 58 | <entry>Y'<subscript>21</subscript></entry> |
| 59 | <entry>Cr<subscript>20</subscript></entry> |
| 60 | <entry>Y'<subscript>22</subscript></entry> |
| 61 | <entry>Cb<subscript>21</subscript></entry> |
| 62 | <entry>Y'<subscript>23</subscript></entry> |
| 63 | <entry>Cr<subscript>21</subscript></entry> |
| 64 | </row> |
| 65 | <row> |
| 66 | <entry>start + 24:</entry> |
| 67 | <entry>Y'<subscript>30</subscript></entry> |
| 68 | <entry>Cb<subscript>30</subscript></entry> |
| 69 | <entry>Y'<subscript>31</subscript></entry> |
| 70 | <entry>Cr<subscript>30</subscript></entry> |
| 71 | <entry>Y'<subscript>32</subscript></entry> |
| 72 | <entry>Cb<subscript>31</subscript></entry> |
| 73 | <entry>Y'<subscript>33</subscript></entry> |
| 74 | <entry>Cr<subscript>31</subscript></entry> |
| 75 | </row> |
| 76 | </tbody> |
| 77 | </tgroup> |
| 78 | </informaltable> |
| 79 | </para> |
| 80 | </formalpara> |
| 81 | |
| 82 | <formalpara> |
| 83 | <title>Color Sample Location.</title> |
| 84 | <para> |
| 85 | <informaltable frame="none"> |
| 86 | <tgroup cols="7" align="center"> |
| 87 | <tbody valign="top"> |
| 88 | <row> |
| 89 | <entry></entry> |
| 90 | <entry>0</entry><entry></entry><entry>1</entry><entry></entry> |
| 91 | <entry>2</entry><entry></entry><entry>3</entry> |
| 92 | </row> |
| 93 | <row> |
| 94 | <entry>0</entry> |
| 95 | <entry>Y</entry><entry>C</entry><entry>Y</entry><entry></entry> |
| 96 | <entry>Y</entry><entry>C</entry><entry>Y</entry> |
| 97 | </row> |
| 98 | <row> |
| 99 | <entry>1</entry> |
| 100 | <entry>Y</entry><entry>C</entry><entry>Y</entry><entry></entry> |
| 101 | <entry>Y</entry><entry>C</entry><entry>Y</entry> |
| 102 | </row> |
| 103 | <row> |
| 104 | <entry>2</entry> |
| 105 | <entry>Y</entry><entry>C</entry><entry>Y</entry><entry></entry> |
| 106 | <entry>Y</entry><entry>C</entry><entry>Y</entry> |
| 107 | </row> |
| 108 | <row> |
| 109 | <entry>3</entry> |
| 110 | <entry>Y</entry><entry>C</entry><entry>Y</entry><entry></entry> |
| 111 | <entry>Y</entry><entry>C</entry><entry>Y</entry> |
| 112 | </row> |
| 113 | </tbody> |
| 114 | </tgroup> |
| 115 | </informaltable> |
| 116 | </para> |
| 117 | </formalpara> |
| 118 | </example> |
| 119 | </refsect1> |
| 120 | </refentry> |