problems with simple face detection - only when it's moving and takes too long

[verybigelephants]

i have tried running this example

https://github.com/ThomasLengeling/KinectPV2/blob/master/KinectPV2/examples/SimpleFaceTracking/SimpleFaceTracking.pde

and i'm a hard time to actually detect and track the face

• first, it takes quite a while to detect it and a lot of moving in front of a monitor. i'm used that simple javascript/opencv face detecting algorighms do this almost instantly. is there perhaps some face fitting configuration that i might have missed?

• but even after the face is detected: it is not detected at all times but only when the head is moving. so when i open my mouth/turn the head a little it detects the face, but when i don't move the face, it stops tracing it

am i missing something?