Depends what's on camera and how smart your software is. A full wavelength of audible sound is between a few centimetres and a few tens of metres. If you have a

Depends what's on camera and how smart your software is. A full wavelength of audible sound is between a few centimetres and a few tens of metres. If you have a few objects in scene at such known distances, you can calculate how far out of phase they are, interpolate them and piece together a much higher effective sampling rate.