gstreamer/docs/plugins/inspect/plugin-videoframe_audiolevel.xml

<plugin>
  <name>videoframe_audiolevel</name>
  <description>Video frame-synchronized audio level</description>
  <filename>../../gst/videoframe_audiolevel/.libs/libgstvideoframe_audiolevel.so</filename>
  <basename>libgstvideoframe_audiolevel.so</basename>
  <version>1.9.90</version>
  <license>LGPL</license>
  <source>gst-plugins-bad</source>
  <package>GStreamer Bad Plug-ins source release</package>
  <origin>Unknown package origin</origin>
  <elements>
    <element>
      <name>videoframe-audiolevel</name>
      <longname>Video-frame audio level</longname>
      <class>Filter/Analyzer/Audio</class>
      <description>Synchronized audio/video RMS Level messenger for audio/raw</description>
      <author>Vivia Nikolaidou &lt;vivia@toolsonair.com&gt;</author>
      <pads>
        <caps>
          <name>asink</name>
          <direction>sink</direction>
          <presence>always</presence>
          <details>audio/x-raw, format=(string){ S8, S16LE, S32LE, F32LE, F64LE }, rate=(int)[ 1, 2147483647 ], channels=(int)[ 1, 2147483647 ]</details>
        </caps>
        <caps>
          <name>vsink</name>
          <direction>sink</direction>
          <presence>always</presence>
          <details>video/x-raw</details>
        </caps>
        <caps>
          <name>asrc</name>
          <direction>source</direction>
          <presence>always</presence>
          <details>audio/x-raw, format=(string){ S8, S16LE, S32LE, F32LE, F64LE }, rate=(int)[ 1, 2147483647 ], channels=(int)[ 1, 2147483647 ]</details>
        </caps>
        <caps>
          <name>vsrc</name>
          <direction>source</direction>
          <presence>always</presence>
          <details>video/x-raw</details>
        </caps>
      </pads>
    </element>
  </elements>
</plugin>