There were four major HDTV systems tested by SMPTE in the late 1970s, and in 1979 an SMPTE study group released A Study of High Definition Television Systems:
১৯৭৯ সালে এসএমপিটিই স্টাডি গ্রুপ কী প্রকাশ করেছিল?
A Study of High Definition Television Systems