How do you create masks?

[meropis]

I am using another method of pose estimation that has used this library to create masks (depth, mask_visib and mask). I am attempting to input 1 RGB image, and I wish the output to be a depth mask, a black and white mask, and a mask_visib. Can anyone point me in the correct direction to be able to do this?

I have attached example images of an RGB image, and its respective masks: