Method and apparatus for encoding or decoding two digital video signals multiplexed in a single-video signal path

摘要

In high-end professional video cameras a triax system is used for transferring various signals back and forth over a single coaxial cable between the camera and a base unit using frequency multiplexing. In current low-cost camera systems several signals are transferred as analogue signals over separate wires or cables. However, the analogue camera CVBS video output signal is replaced by a standard serial SDI signal from the camera to a base unit, achieving a maximum data rate of 270 Mbit/s. According to the invention, a single SDI or HDSDI connection is used for transmitting a digital playback video signal as well as a digital teleprompter video signal from the base unit to the camera. A one-dimensional adaptive dynamic range compression is used to reduce the data word length of the two video signals to be transmitted via the SDI/HDSDI connection. To one of the two video signals a smaller data word length is assigned than to the data word length of the other one.