A method and apparatus for three-dimensional image viewing of an image display employs a pair of viewing glasses having left and right side lenses for alternate left-eye and right-eye image viewing by alternately blocking and passing left and right-eye image views from the image display. An image monitor is used to detect lens sync control information interleaved or embedded with image frames of the image display. The lens sync control information detected by the image monitor is decoded into left and right lens control signals for alternately blocking and passing of left and right-eye image views by the left and right side lenses, respectively, in order to generate three-dimensional image viewing.