From: Eduardo Valentin <eduardo.valentin@xxxxxxxxx> # HG changeset patch # User Eduardo Valentin <eduardo.valentin@xxxxxxxxx> # Date 1242209424 -10800 # Node ID ccae4c3150d272235cc2b19af8e9adb2e8b2e5f5 # Parent 6220548f4843ce4d19868dfcf5316d6b58a77824 This single patch adds documentation description for FM Transmitter (FMTX) Extended Control Class and its Control IDs. The text was added under "Extended Controls" section. Priority: normal Signed-off-by: Eduardo Valentin <eduardo.valentin@xxxxxxxxx> diff -r 6220548f4843 -r ccae4c3150d2 v4l2-spec/controls.sgml --- a/v4l2-spec/controls.sgml Wed May 27 11:56:46 2009 +0300 +++ b/v4l2-spec/controls.sgml Wed May 13 13:10:24 2009 +0300 @@ -458,6 +458,12 @@ <para>Unfortunately, the original control API lacked some features needed for these new uses and so it was extended into the (not terribly originally named) extended control API.</para> + + <para>Even though the MPEG encoding API was the first effort +to use the Extended Control API, nowadays there are also other classes +of Extended Controls, such as Camera Controls and FM Transmitter Controls. +The Extended Controls API as well as all Extended Controls classes are +described in the following text.</para> </section> <section> @@ -1816,6 +1822,200 @@ </tgroup> </table> </section> + + <section id="fmtx-controls"> + <title>FM Transmitter Control Reference</title> + + <para>The FM Transmitter (FMTX) class includes controls for common features of +FM transmissions capable devices. Currently this class include parameters for audio +compression, pilot tone generation, audio deviation limiter, RDS transmission and +tuning power features.</para> + + <table pgwide="1" frame="none" id="fmtx-control-id"> + <title>FMTX Control IDs</title> + + <tgroup cols="4"> + <colspec colname="c1" colwidth="1*"> + <colspec colname="c2" colwidth="6*"> + <colspec colname="c3" colwidth="2*"> + <colspec colname="c4" colwidth="6*"> + <spanspec namest="c1" nameend="c2" spanname="id"> + <spanspec namest="c2" nameend="c4" spanname="descr"> + <thead> + <row> + <entry spanname="id" align="left">ID</entry> + <entry align="left">Type</entry> + </row><row rowsep="1"><entry spanname="descr" align="left">Description</entry> + </row> + </thead> + <tbody valign="top"> + <row><entry></entry></row> + <row> + <entry spanname="id"><constant>V4L2_CID_FMTX_CLASS</constant> </entry> + <entry>class</entry> + </row><row><entry spanname="descr">The FMTX class +descriptor. Calling &VIDIOC-QUERYCTRL; for this control will return a +description of this control class.</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_RDS_ENABLED</constant> </entry> + <entry>boolean</entry> + </row> + <row><entry spanname="descr">Enables or disables the RDS transmission feature.</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_RDS_PI</constant> </entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">Sets the RDS Programme Identification field +for transmission.</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_RDS_PTY</constant> </entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">Sets the RDS Programme Type field for transmission. +This coding of up to 31 pre-defined programme types.</entry> + </row> +<!-- + <row> + <entry spanname="id"><constant>V4L2_CID_RDS_PS_NAME</constant> </entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">.</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_RDS_RADIO_TEXT</constant> </entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">.</entry> + </row> +--> + <row> + <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_ENABLED</constant> </entry> + <entry>boolean</entry> + </row> + <row><entry spanname="descr">Enables or disables the audio deviation limiter feature. +The limiter is useful when trying to maximize the audio volume, minimize receiver-generated +distortion and prevent overmodulation. +</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_RELEASE_TIME</constant> </entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">Sets the audio deviation limiter feature release time. +The unit, step and range are driver-specific.</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_AUDIO_LIMITER_DEVIATION</constant> </entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">Configures audio frequency deviation level in Hz. +The range and step are driver-specific.</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_ENABLED</constant> </entry> + <entry>boolean</entry> + </row> + <row><entry spanname="descr">Enables or disables the audio compression feature. +This feature amplifies signals below the threshold by a fixed gain and compresses audio +signals above the threshold by the ratio of Threshold/(Gain + Threshold).</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_GAIN</constant> </entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">Sets the gain for audio compression feature. It is +a dB value. The range and step are driver-specific.</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_THRESHOLD</constant> </entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">Sets the threshold level for audio compression freature. +It is a dB value. The range and step are driver-specific.</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_ATTACK_TIME</constant> </entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">Sets the attack time for audio compression feature. +It is a useconds value. The range and step are driver-specific.</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_AUDIO_COMPRESSION_RELEASE_TIME</constant> </entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">Sets the release time for audio compression feature. +It is a useconds value. The range and step are driver-specific.</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_ENABLED</constant> </entry> + <entry>boolean</entry> + </row> + <row><entry spanname="descr">Enables or disables the pilot tone generation feature.</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_DEVIATION</constant> </entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">Configures pilot tone frequency deviation level. Unit is +in Hz. The range and step are driver-specific.</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_PILOT_TONE_FREQUENCY</constant> </entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">Configures pilot tone frequency value. Unit is +in Hz. The range and step are driver-specific.</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_PREEMPHASIS</constant> </entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">Configures the pre-emphasis value for broadcasting. +A pre-emphasis filter is applied to the broadcast to accentuate the high audio frequencies. +Depending on the region, a time constant of either 50 or 75 useconds is used. Possible values +are:</entry> + </row><row> + <entrytbl spanname="descr" cols="2"> + <tbody valign="top"> + <row> + <entry><constant>V4L2_FMTX_PREEMPHASIS_DISABLED</constant> </entry> + <entry>No pre-emphasis is applied.</entry> + </row> + <row> + <entry><constant>V4L2_FMTX_PREEMPHASIS_50_uS</constant> </entry> + <entry>A pre-emphasis of 50 uS is used.</entry> + </row> + <row> + <entry><constant>V4L2_FMTX_PREEMPHASIS_75_uS</constant> </entry> + <entry>A pre-emphasis of 75 uS is used.</entry> + </row> + </tbody> + </entrytbl> + + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_TUNE_POWER_LEVEL</constant> </entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">Sets the output power level for signal transmission. +Unit is in dBuV. Range and step are driver-specific.</entry> + </row> + <row> + <entry spanname="id"><constant>V4L2_CID_TUNE_ANTENNA_CAPACITOR</constant> </entry> + <entry>integer</entry> + </row> + <row><entry spanname="descr">This selects the value of antenna tuning capacitor +manually or automatically if set to zero. Unit, range and step are driver-specific.</entry> + </row> + <row><entry></entry></row> + </tbody> + </tgroup> + </table> + </section> </section> <!-- -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html