- <para>The <constant>V4L2_YCBCR_ENC_601</constant> encoding as described above is the
-default for this colorspace, but it can be overridden with <constant>V4L2_YCBCR_ENC_709</constant>,
-in which case the Rec. 709 Y'CbCr encoding is used.</para>
- <variablelist>
- <varlistentry>
- <term>The xvYCC 601 encoding (<constant>V4L2_YCBCR_ENC_XV601</constant>, <xref linkend="xvycc" />) is similar
-to the BT.601 encoding, but it allows for R', G' and B' values that are outside the range
-[0…1]. The resulting Y', Cb and Cr values are scaled and offset:</term>
- <listitem>
- <para>Y' = (219 / 255) * (0.299R' + 0.587G' + 0.114B') + (16 / 255)</para>
- <para>Cb = (224 / 255) * (-0.169R' - 0.331G' + 0.5B')</para>
- <para>Cr = (224 / 255) * (0.5R' - 0.419G' - 0.081B')</para>
- </listitem>
- </varlistentry>
- </variablelist>
- <para>Y' is clamped to the range [0…1] and Cb and Cr are clamped
-to the range [-0.5…0.5]. The non-standard xvYCC 709 encoding can also be used by selecting
-<constant>V4L2_YCBCR_ENC_XV709</constant>. The xvYCC encodings always use full range
-quantization.</para>