Has nothing to do with whether it's a camera or anything else.
39:3-74. Windshields must be unobstructed and equipped with cleaners
Every motor vehicle having a windshield shall be equipped with at least one device in good working order for cleaning rain, snow or other moisture from the windshield so as to provide clear vision for the driver, and all such devices shall be so constructed and installed as to be operated or controlled by the driver.
No person shall drive any motor vehicle with any sign, poster, sticker or other non-transparent material upon the front windshield, wings, deflectors, side shields, corner lights adjoining windshield or front side windows of such vehicle other than a certificate or other article required to be so displayed by statute or by regulations of the commissioner.
No person shall drive any vehicle so constructed, equipped or loaded as to unduly interfere with the driver's vision to the front and to the sides.
That gives an officer quite a bit of discretion in deciding whether your view is obstructed or not.
Consider mounting it above the rear-view mirror or down on the dash at the bottom of the windshield.