Analog video classification
There are three main formats of analog
video signals; PAL\NTSC and SECAM, in which PAL is called P system and NTSC is
called N system, as is often said.
PAL (phase Alternating Line) is a TV system
established in 1965. With the exception of NTSC in parts of North America and
East Asra and SECAM is adopted in most parts of the world, which serves 25
frames per second.
NTSC is the color television broadcasting
standards formulated by National televition setting committee in 1952. It is
adopted by most of the American countries, like America, Canada and Mexico, and
China Taiwan, Japan, Korea and Philippine, as well as some TV company in
Hongkong, South China. It serves 30 frames per second.
SECAM: At present, countries that adopted
SECAM is mainly commonwealth of In dependent stares, such as Russia AND France,
Egypt and some French-speaking countries
in Africa.
Therefore, in order to ensure that the
analog video output of the movement can be used normally, movement will output
two kinds of analog video: PAL and NTSC for choice。