To see all options, please do a ./configure --help. Many options are self-explanatory others are not. Please feel free to add here.
Sets up the build for a binary that can run on Android (arm-linux-androideabi-)
Enables the opensource implementation of Apple's zero configuration protocol. For example, a user can plug their computer into a network and have Avahi automatically advertise the network services running on its machine. Avahi's "ihavA" advertisement results in adding user access to printers, files and other networked services.
For encryption, automatically enabled by cwc or cccam. Tvheadend supports connecting to card clients via the cwc (newcamd) and capmt (linux network dvbapi) protocols for so-called 'softcam' descrambling. One example is the OSCAM package that lets you use your regular CA (Conditional Access) smartcard.
For excryption, disable Code Word Client
For excryption, disable another Code Word Client
Stops the inclusion/download of scan files. Digital TV scan tables.
Disables the Opus encoding audio format. Unclear who uses it
Disables the Ogg/Vorbis encoding audio format.
Disable linuxdvb in case you use iptv only.
Sat>IP allows the satellite TV distribution to share a data network and enables display and viewing of the signals on any multimedia IP device equipped with suitable software. A Sat>IP server receives satellite signals and distributes them to IP-connected clients, such as PCs, Tablets or smartphones.
Disable timeshift or the ability to pause a programme you view for later viewing.
In case you do not have zlib and cannot install it. It is used for compression of web content (on the fly) when serving static pages. It's also used in the file bundling builds where the bundled resources may in fact be compressed in the bundle and some will need decompressing before they can be used. But if you disable zlib the bundle will simply not be compressed.