Video Connectors

Commonly used connectors for video interfaces

The video signal is often transmitted separately from the audio signal, and the video transmission quality: composite video signal < S video signal < color difference component signal < VGA < DVI < HDMI.

1. Composite video signal (standard AV interface)

Composite video interface (AV interface or Video interface) is the most common video interface at present, and almost all TVs and DVD players have this interface. It is a video interface that separates audio and video. It is generally composed of three independent RCA plugs (also called plum blossom interface and RCA interface). Among them, the V interface is connected to the mixed video signal, which is a yellow jack; the L interface is connected to the left channel sound signal, which is White socket; R interface is connected to the right channel sound signal, which is a red socket. The composite video interface has two types of terminals: RCA terminals and BNC terminals. The RCA terminal is commonly referred to as the lotus head and the lotus seat, and the BNC terminal is the BNC head and the BNC seat. The RCA terminal can be used in both composite video interface and audio interface. If used in audio interface, it is usually called 3.5 lotus head.

1-1>The BNC connector

75 represents the resistance, and the following 3 and 5 represent its insulation outer diameter (3mm/5mm). Video cable: 75-3 transmission distance is about 200 meters; 75-5 transmission distance is about 500 meters; 75-7 transmission speed distance is about 500--800 meters; 75-9 transmission speed distance is about 1000--1500 meters; 75 -12 speed transmission distance is about 2000----3500 meters.

1-2>RCA connector (commonly known as lotus head)

1-3>S-terminal (or Y/C)

S interface is also a very common interface, its full name is Separate Video, also known as SUPER VIDEO. The S-Video connection specification is a specification developed by the Japanese. S refers to "SEPARATE", which separates the output of luminance and chrominance, avoiding the mutual interference of luminance and chrominance when outputting mixed video signals. The S interface is actually a five-core interface, consisting of two channels of luminance signal, two channels of video chrominance signal, and one channel of common shielded ground wire, a total of five core wires.

1-4>Video component input interface

The component video interface is also called the component video output/input interface, also called 3RCA. Component video interfaces usually use YPbPr and YCbCr labels. The component video interface/component video terminal is based on the S terminal, and the blue difference (b) and red difference (r) in the chrominance (C) signal are sent separately. The resolution can reach more than 600 lines, and can input a variety of Level signal, from the most basic 480i to 480P with frequency doubling scan, even 720P, 1080i and so on. For example, the YPbPr interface on the graphics card uses a 9-pin S terminal (mini-DIN) and then transmits it independently through the color difference output line.

1-5>VGA

VGA is the abbreviation of Video Graphics Adapter, the signal type is analog type, the interface of the video output terminal is a 15-pin female socket, and the interface of the video input terminal is a 15-pin male plug. The VGA terminal includes red (R), yellow (G), basket (B) three primary color signals and line (HS), field (VS) scan signals.

1-6>DVI+DP

DVI interface and VGA are the most commonly used interfaces in computers. Different from VGA, DVI is an interface for full digital transmission, so it ensures completely uncompressed transmission in terms of picture quality. But it does not mean that it is only an interface in the computer. In fact, both VGA and DVI are widely used in other fields, such as digital TV, etc.

Standard DP interface: about 17MM wide, about 6.3MM high;
DVI-D interface: DVI 24+1 interface, about 24MM wide and 7.8MM high, DVI-D can only transmit digital signals;
DVI-I interface: DVI 24+5 interface, about 24MM wide and 7.8MM high, DVI-I can transmit digital signals and analog signals, and can be used for digital-to-analog conversion from DVI to VGA.

1-7>DB

The D-type interface is a common data interface on computers. It is named after the shape of the letter D.
DB9: about 18MM wide, about 9MM high, the serial communication interface RS232 is the DB9 pin interface;
DB25: width about 38MM, height about 8MM, parallel printer LPT 25 holes --DB25DB36: width about 50MM, height about 13MM, parallel printer 36 pins

1-8>Apple series

Apple's proprietary DVI connector combines analog and video signals plus USB and power cables into one. Today, Apple uses standard DVI connectors, but you may find these monitor connectors on older devices. Apple series interfaces are mainly divided into 3 types, as shown in the figure above.
--Mini DP interface: about 7.6MM wide and 4.6MM high. The Mini DP interface is consistent with the DP interface protocol and can be converted to each other;
--ThunderBolt: Thunderbolt interface, about 7.6MM wide and 4.6MM high.
--Mini DVI interface: about 11.3MM wide and 7MM high.

1-9>HDMI

High Definition Multimedia Interface (English: High Definition Multimedia Interface, HDMI) is a digital video/audio interface technology. It is a dedicated digital interface suitable for image transmission. It can transmit audio and video signals at the same time. The maximum data transmission speed is 5Gbps . At the same time, there is no need for digital/analog or analog/digital conversion before signal transmission. HDMI can be combined with Broadband Digital Content Protection (HDCP) to prevent unauthorized copying of copyrighted audio and video content. There are three types of common HDMI interfaces, as shown above.
HDMI A TYPE: standard HDMI interface, about 15MM wide and 5MM high;
HDMI C TYPE: Mini HDMI interface, about 10.5MM wide, 2.5MM high;
HDMI D TYPE: Micro HDMI interface, about 6MM wide, about 2.3MM high, high-definition interface for digital devices such as mobile phones