Introduction
graphics card handling image to display on the display device, then the output interface of the graphics card, now the most common mainly: VGA interface, DVI interface, S terminal, HDMI these output interfaces.
Details
(1) VGA (Video Graphics Array Video Graphic Array) interface, that is, D-SUB15 interface, the function is to output the conversion analog signal to CRT or LCD Monitor. Display, including LCD, mostly using VGA interfaces as standard input methods. The standard VGA interface uses an asymmetric distribution of 15PIN connection mode, its working principle is to simulate the image signal stored in digital format in the RAMDAC into an analog high frequency signal in the RAMDAC in the RAMDAC, and then output to the display image. Its advantages have crosstalk, no circuit combined with separation loss.
(2) DVI (Digital Visual Interface Digital Video Interface) interface, video signal does not need to conversion, no attenuation or distortion, the display effect is significantly, will be an alternative to the VGA interface. VGA is based on analog signal transmission. The number / mode conversion process and analog transport process will have a certain degree of signal loss during the period, and the DVI interface is a complete digital video interface, which can generate the graphics card The digital signal is inoperable to the display, thereby avoiding the loss of signals during transmission. The DVI interface can be divided into two: only support DVI-D interfaces of digital signals and DVI-I interfaces that support digital and analog signals. However, due to the popularity of cost issues and VGA, the current DVI interface cannot fully replace VGA interfaces.
(3) S-VIDEO (S terminal, Separate Video), S terminal is also called two-point video interface, generally uses a five-wire joint, which is used to separate the output of brightness and chrominance. The main function is to overcome the mutual interference of the brightness heel chroma during the composite output of the video program. The brightness and chrominance separation output of the S terminal can increase the picture quality, and the content displayed on the computer screen is very clearly output to the display device such as the projector.
(4) High Definition Multimedia Interface (English: High Definition MultiMedia Interface, HDMI) is a digital video / audio interface technology that is a special-purpose digital interface suitable for image transmission, which can transmit audio simultaneously And audio and video signals, the highest data transmission speed is 5Gbps. There is also no need to perform several / modes or modes / digital conversions before signal transmission. HDMI can match broadband digital content protection (HDCP) to prevent the audio and video content with copyright from being authorized to replicate. The additional space of HDMI can be applied in the audio and video format upgraded in the future. And because a 1080P video and an 8-channel audio signal require less than 4Gbps, HDMI has a large amount. This allows it to connect DVD players, receivers, and PRRs with a cable.