E-MAC

E-MAC (Extended MAC) is 16:9 version of C-MAC. Originally E-MAC was designed for 15:9 pictures, it later adopted the 16:9 aspect ratio.
* In E-MAC all the 4:3 information is transmitted exactly as in C-MAC so that C-MAC receivers are still compatible.
* E-MAC hides extra luminance and chrominance information in the field blanking interval and parts of the line blanking interval.
* E-MAC has a lower data capacity because luminance is hidden where data would usually be located.
* A 'steering' signal is transmitted to indicate to the 16:9 receiver whereabouts the 4:3 picture information.
* E-MAC receivers stitch the 4:3 and helper widescreen datat into a seameless 16:9 picture.