Set stereo depth.
If follow_video is true then the pixel offset value from the video metadata will be used to set the
perceived depth. Otherwise, the z value specified will cause the left eye buffer
content to be shifted on the x-axis by +z and the right eye buffer to be shifted
by -z. A positive z value will cause the layer to appear closer than
the TV plane while a negative z value will make the layer appear farther away. The
depth is limited to a value between +DLSO_FIXED_LIMIT and -DLSO_FIXED_LIMIT.