Dicaffeine PTZ support

In Dicaffeine there is a build-in support for PTZ, both as a receiver or sender.

For sender it's easy to control the stream directly from the GUI or via joystick.

Receiver requires additional configuration of GPIO pins in:

/etc/dicaffeine/dserver.json

on line:

"ptz_gpio": [17, 22, 23, 27],

you can use the default configuration or edit the pins as described on official Raspberry page.