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Diffstat (limited to 'Documentation/DocBook/media/v4l/vidioc-encoder-cmd.xml')
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diff --git a/Documentation/DocBook/media/v4l/vidioc-encoder-cmd.xml b/Documentation/DocBook/media/v4l/vidioc-encoder-cmd.xml deleted file mode 100644 index 70a4a08e9404..000000000000 --- a/Documentation/DocBook/media/v4l/vidioc-encoder-cmd.xml +++ /dev/null @@ -1,197 +0,0 @@ -<refentry id="vidioc-encoder-cmd"> - <refmeta> - <refentrytitle>ioctl VIDIOC_ENCODER_CMD, VIDIOC_TRY_ENCODER_CMD</refentrytitle> - &manvol; - </refmeta> - - <refnamediv> - <refname>VIDIOC_ENCODER_CMD</refname> - <refname>VIDIOC_TRY_ENCODER_CMD</refname> - <refpurpose>Execute an encoder command</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <funcsynopsis> - <funcprototype> - <funcdef>int <function>ioctl</function></funcdef> - <paramdef>int <parameter>fd</parameter></paramdef> - <paramdef>int <parameter>request</parameter></paramdef> - <paramdef>struct v4l2_encoder_cmd *<parameter>argp</parameter></paramdef> - </funcprototype> - </funcsynopsis> - </refsynopsisdiv> - - <refsect1> - <title>Arguments</title> - - <variablelist> - <varlistentry> - <term><parameter>fd</parameter></term> - <listitem> - <para>&fd;</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>request</parameter></term> - <listitem> - <para>VIDIOC_ENCODER_CMD, VIDIOC_TRY_ENCODER_CMD</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>argp</parameter></term> - <listitem> - <para></para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Description</title> - - <para>These ioctls control an audio/video (usually MPEG-) encoder. -<constant>VIDIOC_ENCODER_CMD</constant> sends a command to the -encoder, <constant>VIDIOC_TRY_ENCODER_CMD</constant> can be used to -try a command without actually executing it.</para> - - <para>To send a command applications must initialize all fields of a - &v4l2-encoder-cmd; and call - <constant>VIDIOC_ENCODER_CMD</constant> or - <constant>VIDIOC_TRY_ENCODER_CMD</constant> with a pointer to this - structure.</para> - - <para>The <structfield>cmd</structfield> field must contain the -command code. The <structfield>flags</structfield> field is currently -only used by the STOP command and contains one bit: If the -<constant>V4L2_ENC_CMD_STOP_AT_GOP_END</constant> flag is set, -encoding will continue until the end of the current <wordasword>Group -Of Pictures</wordasword>, otherwise it will stop immediately.</para> - - <para>A <function>read</function>() or &VIDIOC-STREAMON; call sends an implicit -START command to the encoder if it has not been started yet. After a STOP command, -<function>read</function>() calls will read the remaining data -buffered by the driver. When the buffer is empty, -<function>read</function>() will return zero and the next -<function>read</function>() call will restart the encoder.</para> - - <para>A <function>close</function>() or &VIDIOC-STREAMOFF; call of a streaming -file descriptor sends an implicit immediate STOP to the encoder, and all buffered -data is discarded.</para> - - <para>These ioctls are optional, not all drivers may support -them. They were introduced in Linux 2.6.21.</para> - - <table pgwide="1" frame="none" id="v4l2-encoder-cmd"> - <title>struct <structname>v4l2_encoder_cmd</structname></title> - <tgroup cols="3"> - &cs-str; - <tbody valign="top"> - <row> - <entry>__u32</entry> - <entry><structfield>cmd</structfield></entry> - <entry>The encoder command, see <xref linkend="encoder-cmds" />.</entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>flags</structfield></entry> - <entry>Flags to go with the command, see <xref - linkend="encoder-flags" />. If no flags are defined for -this command, drivers and applications must set this field to -zero.</entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>data</structfield>[8]</entry> - <entry>Reserved for future extensions. Drivers and -applications must set the array to zero.</entry> - </row> - </tbody> - </tgroup> - </table> - - <table pgwide="1" frame="none" id="encoder-cmds"> - <title>Encoder Commands</title> - <tgroup cols="3"> - &cs-def; - <tbody valign="top"> - <row> - <entry><constant>V4L2_ENC_CMD_START</constant></entry> - <entry>0</entry> - <entry>Start the encoder. When the encoder is already -running or paused, this command does nothing. No flags are defined for -this command.</entry> - </row> - <row> - <entry><constant>V4L2_ENC_CMD_STOP</constant></entry> - <entry>1</entry> - <entry>Stop the encoder. When the -<constant>V4L2_ENC_CMD_STOP_AT_GOP_END</constant> flag is set, -encoding will continue until the end of the current <wordasword>Group -Of Pictures</wordasword>, otherwise encoding will stop immediately. -When the encoder is already stopped, this command does -nothing. mem2mem encoders will send a <constant>V4L2_EVENT_EOS</constant> event -when the last frame has been encoded and all frames are ready to be dequeued and -will set the <constant>V4L2_BUF_FLAG_LAST</constant> buffer flag on the last -buffer of the capture queue to indicate there will be no new buffers produced to -dequeue. This buffer may be empty, indicated by the driver setting the -<structfield>bytesused</structfield> field to 0. Once the -<constant>V4L2_BUF_FLAG_LAST</constant> flag was set, the -<link linkend="vidioc-qbuf">VIDIOC_DQBUF</link> ioctl will not block anymore, -but return an &EPIPE;.</entry> - </row> - <row> - <entry><constant>V4L2_ENC_CMD_PAUSE</constant></entry> - <entry>2</entry> - <entry>Pause the encoder. When the encoder has not been -started yet, the driver will return an &EPERM;. When the encoder is -already paused, this command does nothing. No flags are defined for -this command.</entry> - </row> - <row> - <entry><constant>V4L2_ENC_CMD_RESUME</constant></entry> - <entry>3</entry> - <entry>Resume encoding after a PAUSE command. When the -encoder has not been started yet, the driver will return an &EPERM;. -When the encoder is already running, this command does nothing. No -flags are defined for this command.</entry> - </row> - </tbody> - </tgroup> - </table> - - <table pgwide="1" frame="none" id="encoder-flags"> - <title>Encoder Command Flags</title> - <tgroup cols="3"> - &cs-def; - <tbody valign="top"> - <row> - <entry><constant>V4L2_ENC_CMD_STOP_AT_GOP_END</constant></entry> - <entry>0x0001</entry> - <entry>Stop encoding at the end of the current <wordasword>Group Of -Pictures</wordasword>, rather than immediately.</entry> - </row> - </tbody> - </tgroup> - </table> - </refsect1> - - <refsect1> - &return-value; - - <variablelist> - <varlistentry> - <term><errorcode>EINVAL</errorcode></term> - <listitem> - <para>The <structfield>cmd</structfield> field is invalid.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EPERM</errorcode></term> - <listitem> - <para>The application sent a PAUSE or RESUME command when -the encoder was not running.</para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> -</refentry> |