Letterbox television system.

摘要

In a method of transmitting an extended television signal comprising a wide aspect ratio picture between two horizontal bars so as to form a standard aspect ratio picture, in which vertical resolution enhancement signals are transmitted to improve the vertical resolution upon display on an enhanced television receiver, this method comprises the steps of separating the vertical resolution enhancement signals into a low-frequency part (DC - 1.5 MHz) and a high-frequency part (1.2 - 2.9 MHz); transmitting the high-frequency part during the horizontal bars, which high-frequency part is not modulated onto a subcarrier; and transmitting the low-frequency part during the horizontal bars after modulation onto a subcarrier (4.43 MHz). <IMAGE>