A bit off topic, but I'm working on a video interviewing startup and one of the things we'd looove to offer is (semi-)automatic Chrome Keying / green screening

A bit off topic, but I'm working on a video interviewing startup and one of the things we'd looove to offer is (semi-)automatic Chrome Keying / green screening to show just a person's torso and face. Might (one of) you know what's the state of the art in research on this topic as well?