It is a composite video multiplexer. Their connection also incorporate 4 inputs L + R audio. The purpose of the device is to select one of 4 input sources and send it to the output.
This selection can be done in 2 ways:
Using the appropriate front button.
Through DMX signal.
In the latter case, VMX 4 provides a channel DMX control, whose value determines which input signal is sent to the output.The 16x2 character LCD display shows information about the current selected entry, the DMX frame received and in that case, the DMX address used.
The applications of this device are varied:
From security camera control, allowing to pass from one to another even programmatically altering DMX random values.
Presentations with live cam recordings and previous video, etc..