Hi Hans, On Sun, Jun 14, 2009 at 1:41 PM, Hans Verkuil<hverkuil@xxxxxxxxx> wrote: > On Friday 12 June 2009 19:30:36 Eduardo Valentin wrote: >> This single patch adds documentation description for FM Modulator (FM_TX) >> Extended Control Class and its Control IDs. The text was added under >> "Extended Controls" section. >> >> Signed-off-by: Eduardo Valentin <eduardo.valentin@xxxxxxxxx> >> --- >> v4l2-spec/Makefile | 1 + >> v4l2-spec/biblio.sgml | 10 +++ >> v4l2-spec/controls.sgml | 205 +++++++++++++++++++++++++++++++++++++++++++++++ >> 3 files changed, 216 insertions(+), 0 deletions(-) >> >> diff --git a/v4l2-spec/Makefile b/v4l2-spec/Makefile >> index 7a19924..bfe2965 100644 >> --- a/v4l2-spec/Makefile >> +++ b/v4l2-spec/Makefile >> @@ -242,6 +242,7 @@ ENUMS = \ >> v4l2_power_line_frequency \ >> v4l2_priority \ >> v4l2_tuner_type \ >> + v4l2_fm_tx_preemphasis \ >> >> STRUCTS = \ >> v4l2_audio \ >> diff --git a/v4l2-spec/biblio.sgml b/v4l2-spec/biblio.sgml >> index b013ece..0921849 100644 >> --- a/v4l2-spec/biblio.sgml >> +++ b/v4l2-spec/biblio.sgml >> @@ -11,6 +11,16 @@ url="http://www.eia.org">http://www.eia.org</ulink>)</corpauthor> >> Service"</title> >> </biblioentry> >> >> + <biblioentry id="en50067"> >> + <abbrev>EN 50067</abbrev> >> + <authorgroup> >> + <corpauthor>CENELEC European Committee for Electrotechnical Standardization >> +(<ulink url="http://www.cenelec.eu">http://www.cenelec.eu</ulink>)</corpauthor> >> + </authorgroup> >> + <title>EN 50067 "Specification of the radio data system (RDS) for >> +VHF/FM sound broadcasting in the frequency range from 87,5 to 108,0 MHz"</title> >> + </biblioentry> >> + >> <biblioentry id="en300294"> >> <abbrev>EN 300 294</abbrev> >> <authorgroup> >> diff --git a/v4l2-spec/controls.sgml b/v4l2-spec/controls.sgml >> index 477a970..0bb6f00 100644 >> --- a/v4l2-spec/controls.sgml >> +++ b/v4l2-spec/controls.sgml >> @@ -458,6 +458,12 @@ video is actually encoded into that format.</para> >> <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 +1822,205 @@ control must support read access and may support write access.</entry> >> </tgroup> >> </table> >> </section> >> + >> + <section id="fm-tx-controls"> >> + <title>FM Transmitter Control Reference</title> >> + >> + <para>The FM Transmitter (FM_TX) 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="fm-tx-control-id"> >> + <title>FM_TX 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_FM_TX_CLASS</constant> </entry> >> + <entry>class</entry> >> + </row><row><entry spanname="descr">The FM_TX 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> > > coding -> encodes Right. > >> + </row> >> + <row> >> + <entry spanname="id"><constant>V4L2_CID_RDS_PS_NAME</constant> </entry> >> + <entry>string</entry> >> + </row> >> + <row><entry spanname="descr">Sets the Programme Service name (PS_NAME) for transmission. >> +It is intended for static display on a receiver. It is the primary aid to listeners in programme service >> +identification and selection. The use of PS to transmit text other than a single eight character name is not permitted.</entry> >> + </row> >> + <row> >> + <entry spanname="id"><constant>V4L2_CID_RDS_RADIO_TEXT</constant> </entry> >> + <entry>string</entry> >> + </row> >> + <row><entry spanname="descr">Sets the Radio Text info for transmission. It is a textual description of >> +what is being broadcasted. If broadcaster wishes to transmit longer PS names, programme-related information or any other >> +text, then RadioText should be used.</entry> > > This is slightly ambiguous. I would suggest changing the ending to: > > "should be used in addition to <constant>V4L2_CID_RDS_PS_NAME</constant>." I see. I'll change this. > >> + </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> > > I thought the unit was useconds? Yeah. Changing. > >> + </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 id="v4l2-fm-tx-preemphasis"><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. The enum v4l2_fm_tx_preemphasis >> +defines possible values for pre-emphasis. Here they are:</entry> >> + </row><row> >> + <entrytbl spanname="descr" cols="2"> >> + <tbody valign="top"> >> + <row> >> + <entry><constant>V4L2_FM_TX_PREEMPHASIS_DISABLED</constant> </entry> >> + <entry>No pre-emphasis is applied.</entry> >> + </row> >> + <row> >> + <entry><constant>V4L2_FM_TX_PREEMPHASIS_50_uS</constant> </entry> >> + <entry>A pre-emphasis of 50 uS is used.</entry> >> + </row> >> + <row> >> + <entry><constant>V4L2_FM_TX_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> >> + >> +<para>For more details about RDS specification, refer to >> +<xref linkend="en50067"> document, from CENELEC.</para> >> + </section> >> </section> >> >> <!-- > > Regards, > > Hans > > -- > Hans Verkuil - video4linux developer - sponsored by TANDBERG Telecom > -- > 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 > -- Eduardo Bezerra Valentin -- 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