2. Digital TV Frontend API¶
The Digital TV frontend API was designed to support three groups of delivery systems: Terrestrial, cable and Satellite. Currently, the following delivery systems are supported:
- Terrestrial systems: DVB-T, DVB-T2, ATSC, ATSC M/H, ISDB-T, DVB-H, DTMB, CMMB
- Cable systems: DVB-C Annex A/C, ClearQAM (DVB-C Annex B)
- Satellite systems: DVB-S, DVB-S2, DVB Turbo, ISDB-S, DSS
The Digital TV frontend controls several sub-devices including:
- Tuner
- Digital TV demodulator
- Low noise amplifier (LNA)
- Satellite Equipment Control (SEC) [1].
The frontend can be accessed through /dev/dvb/adapter?/frontend?
.
Data types and ioctl definitions can be accessed by including
linux/dvb/frontend.h
in your application.
Note
Transmission via the internet (DVB-IP) and MMT (MPEG Media Transport) is not yet handled by this API but a future extension is possible.
[1] | On Satellite systems, the API support for the Satellite Equipment Control (SEC) allows to power control and to send/receive signals to control the antenna subsystem, selecting the polarization and choosing the Intermediate Frequency IF) of the Low Noise Block Converter Feed Horn (LNBf). It supports the DiSEqC and V-SEC protocols. The DiSEqC (digital SEC) specification is available at Eutelsat. |