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-rw-r--r--Documentation/DocBook/v4l/compat.xml126
1 files changed, 69 insertions, 57 deletions
diff --git a/Documentation/DocBook/v4l/compat.xml b/Documentation/DocBook/v4l/compat.xml
index b9dbdf9..b42b935 100644
--- a/Documentation/DocBook/v4l/compat.xml
+++ b/Documentation/DocBook/v4l/compat.xml
@@ -2332,15 +2332,26 @@ more information.</para>
</listitem>
</orderedlist>
</section>
- </section>
+ <section>
+ <title>V4L2 in Linux 2.6.34</title>
+ <orderedlist>
+ <listitem>
+ <para>Added
+<constant>V4L2_CID_IRIS_ABSOLUTE</constant> and
+<constant>V4L2_CID_IRIS_RELATIVE</constant> controls to the
+ <link linkend="camera-controls">Camera controls class</link>.
+ </para>
+ </listitem>
+ </orderedlist>
+ </section>
- <section id="other">
- <title>Relation of V4L2 to other Linux multimedia APIs</title>
+ <section id="other">
+ <title>Relation of V4L2 to other Linux multimedia APIs</title>
- <section id="xvideo">
- <title>X Video Extension</title>
+ <section id="xvideo">
+ <title>X Video Extension</title>
- <para>The X Video Extension (abbreviated XVideo or just Xv) is
+ <para>The X Video Extension (abbreviated XVideo or just Xv) is
an extension of the X Window system, implemented for example by the
XFree86 project. Its scope is similar to V4L2, an API to video capture
and output devices for X clients. Xv allows applications to display
@@ -2351,7 +2362,7 @@ capture or output still images in XPixmaps<footnote>
extension available across many operating systems and
architectures.</para>
- <para>Because the driver is embedded into the X server Xv has a
+ <para>Because the driver is embedded into the X server Xv has a
number of advantages over the V4L2 <link linkend="overlay">video
overlay interface</link>. The driver can easily determine the overlay
target, &ie; visible graphics memory or off-screen buffers for a
@@ -2360,16 +2371,16 @@ overlay, scaling or color-keying, or the clipping functions of the
video capture hardware, always in sync with drawing operations or
windows moving or changing their stacking order.</para>
- <para>To combine the advantages of Xv and V4L a special Xv
+ <para>To combine the advantages of Xv and V4L a special Xv
driver exists in XFree86 and XOrg, just programming any overlay capable
Video4Linux device it finds. To enable it
<filename>/etc/X11/XF86Config</filename> must contain these lines:</para>
- <para><screen>
+ <para><screen>
Section "Module"
Load "v4l"
EndSection</screen></para>
- <para>As of XFree86 4.2 this driver still supports only V4L
+ <para>As of XFree86 4.2 this driver still supports only V4L
ioctls, however it should work just fine with all V4L2 devices through
the V4L2 backward-compatibility layer. Since V4L2 permits multiple
opens it is possible (if supported by the V4L2 driver) to capture
@@ -2377,83 +2388,84 @@ video while an X client requested video overlay. Restrictions of
simultaneous capturing and overlay are discussed in <xref
linkend="overlay" /> apply.</para>
- <para>Only marginally related to V4L2, XFree86 extended Xv to
+ <para>Only marginally related to V4L2, XFree86 extended Xv to
support hardware YUV to RGB conversion and scaling for faster video
playback, and added an interface to MPEG-2 decoding hardware. This API
is useful to display images captured with V4L2 devices.</para>
- </section>
+ </section>
- <section>
- <title>Digital Video</title>
+ <section>
+ <title>Digital Video</title>
- <para>V4L2 does not support digital terrestrial, cable or
+ <para>V4L2 does not support digital terrestrial, cable or
satellite broadcast. A separate project aiming at digital receivers
exists. You can find its homepage at <ulink
url="http://linuxtv.org">http://linuxtv.org</ulink>. The Linux DVB API
has no connection to the V4L2 API except that drivers for hybrid
hardware may support both.</para>
- </section>
+ </section>
- <section>
- <title>Audio Interfaces</title>
+ <section>
+ <title>Audio Interfaces</title>
- <para>[to do - OSS/ALSA]</para>
+ <para>[to do - OSS/ALSA]</para>
+ </section>
</section>
- </section>
- <section id="experimental">
- <title>Experimental API Elements</title>
+ <section id="experimental">
+ <title>Experimental API Elements</title>
- <para>The following V4L2 API elements are currently experimental
+ <para>The following V4L2 API elements are currently experimental
and may change in the future.</para>
- <itemizedlist>
- <listitem>
- <para>Video Output Overlay (OSD) Interface, <xref
+ <itemizedlist>
+ <listitem>
+ <para>Video Output Overlay (OSD) Interface, <xref
linkend="osd" />.</para>
- </listitem>
+ </listitem>
<listitem>
- <para><constant>V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY</constant>,
+ <para><constant>V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY</constant>,
&v4l2-buf-type;, <xref linkend="v4l2-buf-type" />.</para>
- </listitem>
- <listitem>
- <para><constant>V4L2_CAP_VIDEO_OUTPUT_OVERLAY</constant>,
+ </listitem>
+ <listitem>
+ <para><constant>V4L2_CAP_VIDEO_OUTPUT_OVERLAY</constant>,
&VIDIOC-QUERYCAP; ioctl, <xref linkend="device-capabilities" />.</para>
- </listitem>
- <listitem>
- <para>&VIDIOC-ENUM-FRAMESIZES; and
+ </listitem>
+ <listitem>
+ <para>&VIDIOC-ENUM-FRAMESIZES; and
&VIDIOC-ENUM-FRAMEINTERVALS; ioctls.</para>
- </listitem>
- <listitem>
- <para>&VIDIOC-G-ENC-INDEX; ioctl.</para>
- </listitem>
- <listitem>
- <para>&VIDIOC-ENCODER-CMD; and &VIDIOC-TRY-ENCODER-CMD;
+ </listitem>
+ <listitem>
+ <para>&VIDIOC-G-ENC-INDEX; ioctl.</para>
+ </listitem>
+ <listitem>
+ <para>&VIDIOC-ENCODER-CMD; and &VIDIOC-TRY-ENCODER-CMD;
ioctls.</para>
- </listitem>
- <listitem>
- <para>&VIDIOC-DBG-G-REGISTER; and &VIDIOC-DBG-S-REGISTER;
+ </listitem>
+ <listitem>
+ <para>&VIDIOC-DBG-G-REGISTER; and &VIDIOC-DBG-S-REGISTER;
ioctls.</para>
- </listitem>
- <listitem>
- <para>&VIDIOC-DBG-G-CHIP-IDENT; ioctl.</para>
- </listitem>
- </itemizedlist>
- </section>
+ </listitem>
+ <listitem>
+ <para>&VIDIOC-DBG-G-CHIP-IDENT; ioctl.</para>
+ </listitem>
+ </itemizedlist>
+ </section>
- <section id="obsolete">
- <title>Obsolete API Elements</title>
+ <section id="obsolete">
+ <title>Obsolete API Elements</title>
- <para>The following V4L2 API elements were superseded by new
+ <para>The following V4L2 API elements were superseded by new
interfaces and should not be implemented in new drivers.</para>
- <itemizedlist>
- <listitem>
- <para><constant>VIDIOC_G_MPEGCOMP</constant> and
+ <itemizedlist>
+ <listitem>
+ <para><constant>VIDIOC_G_MPEGCOMP</constant> and
<constant>VIDIOC_S_MPEGCOMP</constant> ioctls. Use Extended Controls,
<xref linkend="extended-controls" />.</para>
- </listitem>
- </itemizedlist>
+ </listitem>
+ </itemizedlist>
+ </section>
</section>
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