Basic knowledge about video Interfaces

1 RF

Antennas and analog closed-circuit connected TVs use RF interfaces. As the most common video connection method, it can transmit analog videos and audio signals at the same time. The rfinterface transmits the signal after the video and audio are mixed encoding. The Display Device Circuit separates and decodes the mixed encoding signal for output imaging. Due to the need for mixed video and audio encoding, the signal will interfere with each other, so its quality output is the worst among all interfaces. Cable and Satellite Television Receivers are also commonly used for RF connections, but in this case they transmit digital signals.

2. Compound videos

Unlike RF interfaces that contain audio signals, composite videos usually use yellow RCA (Lotus outlet) connectors. "Combination" means the analog signal that transmits the brightness and color signals in the same channel. However, if the TV cannot properly separate the two signals, virtual shadows will appear.

3 S TerminalThe S-video (S-video) connection adopts y/C (brightness/color) separated output and uses a four-core line to transmit signals. The interface is a four-pin interface. In the interface, the two pins are grounded, and the other two pins transmit the brightness and color signals respectively. Because the brightness and color signals are sent separately, the effect of the S terminal is better than that of the composite video. However, the anti-interference capability of the S terminal is weak, so the length of the S terminal line should not exceed 7 meters.

4 chromatic aberrationThe color difference (Component) is usually marked as Y/Pb/PR. Each cable and interface are marked in red, green, and blue colors. The green cable (y) transmits the Brightness Signal. Blue and red cables (PB and PR) Transmit color difference signals. The effect of chromatic aberration is better than that of terminal S. Therefore, many DVD and HD playback devices use this interface. If high-quality cables and interfaces are used, even if a 10-meter-long cable is used, the poor cables can transmit excellent pictures.

5 VGAVGA (video graphics array) also has a name named D-sub. VGA interfaces have a total of 15 pins, divided into three rows, each with five holes. This is the most widely used interface type on the graphics card. Most graphics cards use this interface. It transmits red, green, and blue analog signals and synchronous signals (horizontal and vertical signals ). Use VGA to connect the device. It is recommended that the length of the cable be less than 10 meters, and be sure that the connector is firmly installed. Otherwise, virtual shadows may appear in the image.

6 DVIDVI (Digital Visual Interface) interface and VGA are the most common interfaces in the computer. Different from VGA, DVI can transmit digital signals without having to undergo digital-analog conversion. Therefore, the image quality is very high. Currently, many HDTV also provide DVI interfaces. It should be noted that the DVI interface has a variety of specifications, commonly DVI-D (digital) and DVI-I (intergrated ). DVI-D can only transmit digital signals, you can use it to connect the graphics card and flat panel TV. The DVI-I can be converted to vga in the DVI-D.

For more information about DVI interfaces, see details about DVI interfaces.

7. HDMIThe High Definition Multimedia Interface (HDMI) interface is a recent interface that transmits full digital signals like DVI. The difference is that the HDMI interface can not only transmit high-definition digital video signals, but also transmit high-quality audio signals at the same time. At the same time, the function is the same as that of the RF interface. However, because fully digital signal transmission is adopted, the image quality is not as bad as that of the RF interface. If you do not have an HDMI interface, you can use an adapter to convert the HDMI interface to a DVI interface, but the audio signal is lost. High quality HDMI cables ensure high quality even if they are 20 meters long.

8 IEEE 1394IEEE 1394, also known as firewire or ilink, can transmit digital videos and audio and machine control signals with high bandwidth and high stability. It is usually used to connect devices such as digital cameras and DVDs. There are two types of IEEE 1394 interfaces: 6-pin hexagonal interfaces and 4-pin small-sized four-dimensional interfaces. The six-pin hexagonal interface can supply power to the connected device, while the four-pin interface cannot.

9 BNC BNC (coaxial cable card annular Interface) interface is mainly used to connect high-end home theater Product And professional video devices. The BNC cable has five connection headers that receive red, green, blue, horizontal, and vertical synchronization signals. The BNC connector reduces the interference between video signals and achieves the optimal signal response. In addition, due to the special design of the BNC interface, the connection is very tight and there is no need to worry about loose interfaces and poor contact.