Skip to content

Commit

Permalink
[media] v4l: Add new YVU420 multi planar fourcc definition
Browse files Browse the repository at this point in the history
This patch adds new 'YM21' fourcc definition for multiplanar YCrCb
pixel format - V4L2_PIX_FMT_YVU420M.

Signed-off-by: Shaik Ameer Basha <shaik.ameer@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
  • Loading branch information
Shaik Ameer Basha authored and Mauro Carvalho Chehab committed Sep 15, 2012
1 parent aa15f47 commit 8ab0238
Show file tree
Hide file tree
Showing 3 changed files with 156 additions and 0 deletions.
154 changes: 154 additions & 0 deletions Documentation/DocBook/media/v4l/pixfmt-yvu420m.xml
Original file line number Diff line number Diff line change
@@ -0,0 +1,154 @@
<refentry id="V4L2-PIX-FMT-YVU420M">
<refmeta>
<refentrytitle>V4L2_PIX_FMT_YVU420M ('YM21')</refentrytitle>
&manvol;
</refmeta>
<refnamediv>
<refname> <constant>V4L2_PIX_FMT_YVU420M</constant></refname>
<refpurpose>Variation of <constant>V4L2_PIX_FMT_YVU420</constant>
with planes non contiguous in memory. </refpurpose>
</refnamediv>

<refsect1>
<title>Description</title>

<para>This is a multi-planar format, as opposed to a packed format.
The three components are separated into three sub-images or planes.

The Y plane is first. The Y plane has one byte per pixel. The Cr data
constitutes the second plane which is half the width and half
the height of the Y plane (and of the image). Each Cr belongs to four
pixels, a two-by-two square of the image. For example,
Cr<subscript>0</subscript> belongs to Y'<subscript>00</subscript>,
Y'<subscript>01</subscript>, Y'<subscript>10</subscript>, and
Y'<subscript>11</subscript>. The Cb data, just like the Cr plane, constitutes
the third plane. </para>

<para>If the Y plane has pad bytes after each row, then the Cr
and Cb planes have half as many pad bytes after their rows. In other
words, two Cx rows (including padding) is exactly as long as one Y row
(including padding).</para>

<para><constant>V4L2_PIX_FMT_YVU420M</constant> is intended to be
used only in drivers and applications that support the multi-planar API,
described in <xref linkend="planar-apis"/>. </para>

<example>
<title><constant>V4L2_PIX_FMT_YVU420M</constant> 4 &times; 4
pixel image</title>

<formalpara>
<title>Byte Order.</title>
<para>Each cell is one byte.
<informaltable frame="none">
<tgroup cols="5" align="center">
<colspec align="left" colwidth="2*" />
<tbody valign="top">
<row>
<entry>start0&nbsp;+&nbsp;0:</entry>
<entry>Y'<subscript>00</subscript></entry>
<entry>Y'<subscript>01</subscript></entry>
<entry>Y'<subscript>02</subscript></entry>
<entry>Y'<subscript>03</subscript></entry>
</row>
<row>
<entry>start0&nbsp;+&nbsp;4:</entry>
<entry>Y'<subscript>10</subscript></entry>
<entry>Y'<subscript>11</subscript></entry>
<entry>Y'<subscript>12</subscript></entry>
<entry>Y'<subscript>13</subscript></entry>
</row>
<row>
<entry>start0&nbsp;+&nbsp;8:</entry>
<entry>Y'<subscript>20</subscript></entry>
<entry>Y'<subscript>21</subscript></entry>
<entry>Y'<subscript>22</subscript></entry>
<entry>Y'<subscript>23</subscript></entry>
</row>
<row>
<entry>start0&nbsp;+&nbsp;12:</entry>
<entry>Y'<subscript>30</subscript></entry>
<entry>Y'<subscript>31</subscript></entry>
<entry>Y'<subscript>32</subscript></entry>
<entry>Y'<subscript>33</subscript></entry>
</row>
<row><entry></entry></row>
<row>
<entry>start1&nbsp;+&nbsp;0:</entry>
<entry>Cr<subscript>00</subscript></entry>
<entry>Cr<subscript>01</subscript></entry>
</row>
<row>
<entry>start1&nbsp;+&nbsp;2:</entry>
<entry>Cr<subscript>10</subscript></entry>
<entry>Cr<subscript>11</subscript></entry>
</row>
<row><entry></entry></row>
<row>
<entry>start2&nbsp;+&nbsp;0:</entry>
<entry>Cb<subscript>00</subscript></entry>
<entry>Cb<subscript>01</subscript></entry>
</row>
<row>
<entry>start2&nbsp;+&nbsp;2:</entry>
<entry>Cb<subscript>10</subscript></entry>
<entry>Cb<subscript>11</subscript></entry>
</row>
</tbody>
</tgroup>
</informaltable>
</para>
</formalpara>

<formalpara>
<title>Color Sample Location.</title>
<para>
<informaltable frame="none">
<tgroup cols="7" align="center">
<tbody valign="top">
<row>
<entry></entry>
<entry>0</entry><entry></entry><entry>1</entry><entry></entry>
<entry>2</entry><entry></entry><entry>3</entry>
</row>
<row>
<entry>0</entry>
<entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
<entry>Y</entry><entry></entry><entry>Y</entry>
</row>
<row>
<entry></entry>
<entry></entry><entry>C</entry><entry></entry><entry></entry>
<entry></entry><entry>C</entry><entry></entry>
</row>
<row>
<entry>1</entry>
<entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
<entry>Y</entry><entry></entry><entry>Y</entry>
</row>
<row>
<entry></entry>
</row>
<row>
<entry>2</entry>
<entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
<entry>Y</entry><entry></entry><entry>Y</entry>
</row>
<row>
<entry></entry>
<entry></entry><entry>C</entry><entry></entry><entry></entry>
<entry></entry><entry>C</entry><entry></entry>
</row>
<row>
<entry>3</entry>
<entry>Y</entry><entry></entry><entry>Y</entry><entry></entry>
<entry>Y</entry><entry></entry><entry>Y</entry>
</row>
</tbody>
</tgroup>
</informaltable>
</para>
</formalpara>
</example>
</refsect1>
</refentry>
1 change: 1 addition & 0 deletions Documentation/DocBook/media/v4l/pixfmt.xml
Original file line number Diff line number Diff line change
Expand Up @@ -708,6 +708,7 @@ information.</para>
&sub-y41p;
&sub-yuv420;
&sub-yuv420m;
&sub-yvu420m;
&sub-yuv410;
&sub-yuv422p;
&sub-yuv411p;
Expand Down
1 change: 1 addition & 0 deletions include/linux/videodev2.h
Original file line number Diff line number Diff line change
Expand Up @@ -368,6 +368,7 @@ struct v4l2_pix_format {

/* three non contiguous planes - Y, Cb, Cr */
#define V4L2_PIX_FMT_YUV420M v4l2_fourcc('Y', 'M', '1', '2') /* 12 YUV420 planar */
#define V4L2_PIX_FMT_YVU420M v4l2_fourcc('Y', 'M', '2', '1') /* 12 YVU420 planar */

/* Bayer formats - see http://www.siliconimaging.com/RGB%20Bayer.htm */
#define V4L2_PIX_FMT_SBGGR8 v4l2_fourcc('B', 'A', '8', '1') /* 8 BGBG.. GRGR.. */
Expand Down

0 comments on commit 8ab0238

Please sign in to comment.