inverted alpha channel of the framebuffer or VGA signal. Alpha
blending makes no sense for destructive overlays.</entry>
</row>
+ <row>
+ <entry><constant>V4L2_FBUF_CAP_SRC_CHROMAKEY</constant></entry>
+ <entry>0x0080</entry>
+ <entry>The device supports Source Chroma-keying. Framebuffer pixels
+with the chroma-key colors are replaced by video pixels, which is exactly opposite of
+<constant>V4L2_FBUF_CAP_CHROMAKEY</constant></entry>
+ </row>
</tbody>
</tgroup>
</table>
output = framebuffer pixel * (1 - alpha) + video pixel * alpha. The
actual alpha depth depends on the framebuffer pixel format.</entry>
</row>
+ <row>
+ <entry><constant>V4L2_FBUF_FLAG_SRC_CHROMAKEY</constant></entry>
+ <entry>0x0040</entry>
+ <entry>Use source chroma-keying. The source chroma-key color is
+determined by the <structfield>chromakey</structfield> field of
+&v4l2-window; and negotiated with the &VIDIOC-S-FMT; ioctl, see <xref
+linkend="overlay" /> and <xref linkend="osd" />.
+Both chroma-keying are mutual exclusive to each other, so same
+<structfield>chromakey</structfield> field of &v4l2-window; is being used.</entry>
+ </row>
</tbody>
</tgroup>
</table>