Vero4K+ and lightberry

I’m not using a capture-device, just a framegrabber.
Thanks for the information, but where do I configure that ?
In my json file, I have
// NO V4L2 GRABBER CONFIG
// FRAME GRABBER CONFIG
“framegrabber” :
{
“width” : 64,
“height” : 64,
“frequency_Hz” : 10.0,
“priority” : 890
}