Commit f658d133 authored by Hans Verkuil's avatar Hans Verkuil Committed by Mauro Carvalho Chehab
Browse files

[media] DocBook media: fix xv601/709 formulas 



The denominator for the scaling and offsets is 256, not 255. Fix this.

Signed-off-by: default avatarHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@osg.samsung.com>
parent 1e8faa59

Documentation/DocBook/media/v4l/pixfmt.xml

+6 −6
Original line number Diff line number Diff line
@@ -790,9 +790,9 @@ case the BT.601 Y'CbCr encoding is used.</para> 
is similar to the Rec. 709 encoding, but it allows for R', G' and B' values that are outside the range

[0&hellip;1]. The resulting Y', Cb and Cr values are scaled and offset:</term>

	  <listitem>

            <para>Y'&nbsp;=&nbsp;(219&nbsp;/&nbsp;255)&nbsp;*&nbsp;(0.2126R'&nbsp;+&nbsp;0.7152G'&nbsp;+&nbsp;0.0722B')&nbsp;+&nbsp;(16&nbsp;/&nbsp;255)</para>

            <para>Cb&nbsp;=&nbsp;(224&nbsp;/&nbsp;255)&nbsp;*&nbsp;(-0.1146R'&nbsp;-&nbsp;0.3854G'&nbsp;+&nbsp;0.5B')</para>

            <para>Cr&nbsp;=&nbsp;(224&nbsp;/&nbsp;255)&nbsp;*&nbsp;(0.5R'&nbsp;-&nbsp;0.4542G'&nbsp;-&nbsp;0.0458B')</para>

            <para>Y'&nbsp;=&nbsp;(219&nbsp;/&nbsp;256)&nbsp;*&nbsp;(0.2126R'&nbsp;+&nbsp;0.7152G'&nbsp;+&nbsp;0.0722B')&nbsp;+&nbsp;(16&nbsp;/&nbsp;256)</para>

            <para>Cb&nbsp;=&nbsp;(224&nbsp;/&nbsp;256)&nbsp;*&nbsp;(-0.1146R'&nbsp;-&nbsp;0.3854G'&nbsp;+&nbsp;0.5B')</para>

            <para>Cr&nbsp;=&nbsp;(224&nbsp;/&nbsp;256)&nbsp;*&nbsp;(0.5R'&nbsp;-&nbsp;0.4542G'&nbsp;-&nbsp;0.0458B')</para>

	  </listitem>

	</varlistentry>

      </variablelist>
@@ -802,9 +802,9 @@ is similar to the Rec. 709 encoding, but it allows for R', G' and B' values that 
to the BT.601 encoding, but it allows for R', G' and B' values that are outside the range

[0&hellip;1]. The resulting Y', Cb and Cr values are scaled and offset:</term>

	  <listitem>

            <para>Y'&nbsp;=&nbsp;(219&nbsp;/&nbsp;255)&nbsp;*&nbsp;(0.299R'&nbsp;+&nbsp;0.587G'&nbsp;+&nbsp;0.114B')&nbsp;+&nbsp;(16&nbsp;/&nbsp;255)</para>

            <para>Cb&nbsp;=&nbsp;(224&nbsp;/&nbsp;255)&nbsp;*&nbsp;(-0.169R'&nbsp;-&nbsp;0.331G'&nbsp;+&nbsp;0.5B')</para>

            <para>Cr&nbsp;=&nbsp;(224&nbsp;/&nbsp;255)&nbsp;*&nbsp;(0.5R'&nbsp;-&nbsp;0.419G'&nbsp;-&nbsp;0.081B')</para>

            <para>Y'&nbsp;=&nbsp;(219&nbsp;/&nbsp;256)&nbsp;*&nbsp;(0.299R'&nbsp;+&nbsp;0.587G'&nbsp;+&nbsp;0.114B')&nbsp;+&nbsp;(16&nbsp;/&nbsp;256)</para>

            <para>Cb&nbsp;=&nbsp;(224&nbsp;/&nbsp;256)&nbsp;*&nbsp;(-0.169R'&nbsp;-&nbsp;0.331G'&nbsp;+&nbsp;0.5B')</para>

            <para>Cr&nbsp;=&nbsp;(224&nbsp;/&nbsp;256)&nbsp;*&nbsp;(0.5R'&nbsp;-&nbsp;0.419G'&nbsp;-&nbsp;0.081B')</para>

	  </listitem>

	</varlistentry>

      </variablelist>