HDMI interface knowledge literacy

With the improvement of the quality of life, people's demand for movie viewing is also increasing, and technologies such as 3D, 4K and HDR have emerged. In terms of data transmission, there are more and more interfaces on the devices to meet the various needs of users. AV interface, DVI interface, HDMI interface, USB interface and HDMI panel mount cable, etc. All are common in life, where HDMI interface is higher.

The meaning of HDMI interface

HDMI, also known as High Definition Multimedia Interface, is a digital video/audio interface technology from YouYiResource.com. It is a special digital interface suitable for image transmission. It can transmit audio and video signals simultaneously, without the need for line/analog or analog/digital conversion before signal transmission.

Simply put, HDMI interface is the interface used to transmit image and sound signals. Content creation devices can transmit images and sound to viewing devices through HDMI with high efficiency. This interface is commonly found in smart TVs, set-top boxes, projectors, and other devices, and its interface is inverted trapezoidal and relatively flat. Pictured below:

Development of HDMI

In fact, DVI was the technology that first appeared in the transmission field instead of DHMI, when the DVI interface was also widely used in the output field. However, with the development of digital high-definition audio-visual technology, the DVI interface began to gradually reveal various problems and even became a bottleneck in the progress of digital imaging technology to a certain extent. Therefore, Hollywood IT manufacturers, flat-panel TV manufacturers and many distributors urgently need a better interface technology to meet the future development of the HD video industry. It is for these reasons that the HDMI standard was born.

1.HDMI can not be hot-swapped

HDMI interface is one of the greater advantages of good use. As long as the use of a cable, all audio and video can be transmitted. And the interface is designed to be very easy to plug and unplug, without pressing any buttons can easily plug and unplug. However, this brings up another issue. If you plug or pull directly in the power on state, it is easy to burn the chip of the HDMI interface. So when you unplug the HDMI cable, do not pull it hot. You must turn off the projector and related connected devices before unplugging.

2. Cheap HDMI cables can be used for short distance transmission

For many of our home users, the projector and other devices that provide the input source are not too far away, usually one to two meters, so we usually choose a 1.5 meter HDMI cable. In the choice of HDMI cable, the distance below 5 meters can be considered short distance transmission, and the choice of HDMI cable is relatively simple. An important factor affecting the quality of the wire is the thickness of the wire, which can be divided into 24, 26, 28, 30 wire. The smaller the number, the thicker the wire diameter, the better the effect. 5 meters or less, choose 28 wire and 30 wire on the line. 1.5-meter line does not exceed 80 yuan, 5-meter line does not exceed 150 yuan.

3. Long-distance transmission of strict requirements for the wire

If the long-distance transmission, the HDMI cable requirements are very strict. In addition to the thickness of the wire diameter, the following factors determine the quality of HDMI cable:

(1) the choice of raw materials: good wire, core wire silver-plated, low-cost cable tin-plated.

(2) production technology: the quality of the manufactured wire is also a world of difference.

(3) shielding effect: equipment produced by low-grade HDMI cable shielding effect is only 80% to 85%, while the high-grade wire shielding efficiency of 95%.

Long-distance transmission, the transmission of 1080i or 720P signal when the difference is not significant, but the transmission of 1080P signal, the requirements of the wire is very strict. Wire quality is not up to standard, the light will appear jumping screen, big red dot, heavy no signal.

So the choice of long-distance lines should be very careful. The choice can not just look at the external thickness of the line. Many lines that look thick are actually just thick skin. In fact, are 28 lines, simply can not transmit 1080P signal. 10m or more HDMI cable transmission 1080P signal, require 24 lines better, or at least ensure that 26 lines. 24 lines, transmission 1080P signal, up to 45m. but 28 lines to transmit 1080P signal, even if the distance of 10 meters can not guarantee the quality.

4.HDMI cabling should be carefully buried in the wall

Many friends want to bury the HDMI cable in the wall in advance for future aesthetic convenience, decoration, preferably with HDMI panel mount cable, this practice must be careful.