A decoder is a circuit that changes a code into a set of signals. It is
called a decoder because it does the reverse of encoding, but we will
begin our study of encoders and decoders with decoders because they are
simpler to design.
Video decoders, also known as video servers, enable an existing analog CCTV
video surveillance system to be integrated with a network video system.
Video decoders play a significant role in installations where many
analog cameras are to be maintained.A
video decoder makes it possible for an analog CCTV system to migrate to
a network video system. It enables users to gain the benefits of
network video without having to discard existing analog equipment such
as analog CCTV cameras and coaxial cabling.