[Config] Introduce calibration option

[vivi90]

I have run some tests with different dancing video materials. Sometimes it recognizes the wrong body size at some frames, because of difficult movements. That doesn't look pretty.

So how about an calibration option to: detect the body size at the beginning of an video or webcam session and set it fixed until the end.

[Arthur151]

Hi, @vivi90 .Good point! Thanks for your suggestion. This feature needs tracking to propogate the body shape. I am developing a temporal method to achieve this.