At present, in the high-definition device, the main interface has DVI, HDMI, VGA interface, wherein the video analog video signal transmitted by VGA, DVI belongs to the digital interface, and HDMI can simultaneously transmit video signals and audio signals. In todays computers and TVs, we can often see these three interfaces. So what is the difference between these three interfaces?
The DVI interface is an interface standard introduced in 1999. The transmission signal of the DVI interface adopts the all-digital format, and corresponds to the VGA interface using the analog signal. The difference between VGA and DVI, first of all, the transmission of VGA analog signal is more troublesome. First, the digital signal in the computer is converted into an analog signal, and the signal is sent to the LCD display, and the display converts the analog signal into a digital signal to form a screen display. In front of everyone, because of this, the signal loss in the middle is serious. Although some pictures can be repaired by software, the higher the resolution of the display, the more blurred the picture will be. Generally, when the analog signal exceeds 1280×1024 resolution, obvious error will occur. The higher the resolution, the more serious.
The VGA interface has a wide range of applications and is the first of the three types of interfaces. The VGA (Video Graphics Array) interface is also called the D-Sub interface. Although the LCD monitor can directly receive digital signals, many low-end products use a VGA interface in order to match the VGA interface card. The VGA interface is a D-type interface with a total of 15 pins on the top, divided into three rows, five in each row. The VGA interface is the most widely used interface type on graphics cards, and most graphics cards have such interfaces.
HDMI (High-Definition Multimedia Interface), often referred to as high-definition multimedia interface, is a new interface that terminates the separation of audio and video in the past; its maximum transmission speed can reach 5Gb/s, in addition to image data, it can transmit up to 8 simultaneously. The audio signal of the channel; the uncompressed digital data transmission can effectively reduce the signal interference and attenuation caused by the digital/class conversion. HDMI is the first digital interface to support all-digital high-definition, multi-channel audio and intelligent format and control command data transmitted over a single cable without compression. The HDMI interface was promoted by Silicon Image USA and jointly developed by a working group jointly established by eight famous consumer electronics manufacturers such as Sony, Hitachi, Panasonic, Philips, Thomson and Toshiba. HDMI's earliest interface specification, HDMI 1.0, was released in December 2002. The current highest version is the HDMI 1.3 specification released in June this year.
HDMI is derived from DVI interface technology, which is mainly based on TMDS signal transmission technology of American Crystal Image Company, which is why HDMI interface and DVI interface can be converted by adapter. American Crystal Image Company is the only integrated circuit design and manufacturing company among the eight HDMI initiators. It is a leader in high-speed serial data transmission technology. Because the TMDS signal transmission technology mentioned below is developed by them, so here is a little Mention it.
At present, the same three-dimensional for a variety of commonly used equipment, launched T200AE high-definition VGA capture card, T100E high-definition DVI digital capture card, T630E high-definition HDMI capture card, etc., has been widely used in various video conferencing, teaching recording, webcast, large Screen integration, video surveillance, electronic classrooms and other engineering fields.