摘要 |
A video display system such as a broadcast receiver or a studio monitor is designed to display both MAC-type input signals and HDTV-type input signals, only the latter being of constant luminance type. For MAC signals a normal Y, U, V to R, G, B, decoder matrix is used comprising amplifiers (18, 20, 22) resistors (24A, 24B, 26A, 26B, 28A, 28B, ) and further amplifiers (24, 26, 28). The output is applied to a CRT display device (30) having a conventional gamma factor. For HDTV signals, the decoder matrix is augmented by a correction matrix having six or eight circuit sections. Each circuit section comprises resistors (42, 44, 46), an operational amplifier (40), and circuitry including diodes (48, 50) for selecting the output only over a portion of the permissible color range. |