Difficult to tell from the video, all I hear is engine noise.
From how you describe it it could be mounts.
Put your car's hand brake on. Then have someone start the car while you look at the engine. It should not move much. Then put your car in first gear and reverse gear and look for movement in engine. It should not move much. Then put your car in gear and accelerate a little (with brakes on) look for movement.
If this method fails then lift of one side from front in such a way that the wheel is not touching the ground. With parking brake on, put your car in gear and accelerate slightly and see where the sound is coming from.