There are small holes bored into the barrel near the muzzle, on both sides. The combustion gasses escape out these "ports" instead of all exiting via the muzzle. The ports are designed so that the gas escapes upwards, thus limiting muzzle climb.
A MagnaPort (other side is a mirror image)
The older "Cutts Compensator"
It is very, very odd that the visible smoke is only coming from the right hand side of the compensator.
Also odd that there is only one choke installed (on the upper barrel).
Photoshop or not, this looks weird. Just the technical end, not his horrible stance and gun handling.