When the first 4K TV launched before several years. Overwhelming advertising let us dizzying. In fact, the experience was not comfortable. One reason is 4K TV is not the same standard. Some manufacturers mislead consumer from panel, signal format and processing chips. The other reason is shortage of 4K material. 4K LED TV became decoration. While, it is totally different to HD LED display field. 4K is the best solution for current ultra HD LED display.
Small pitch display facing high-end application challenge
As technology continues to mature, small pixel pitch led display are widely used in high-end application occasion for its advantages. High-end applications have higher and higher requirements on the display effects. For example, some require the best display. Playing material must be customized and pixel to pixel display. That means video material must be customized according to the real resolution of HD LED video wall. Video signal pixel to pixel display on the led without any zoom. Then single 1080p full HD port cannot meet the small pitch ultra resolution display requirements.
Traditional and complicated non-4K solution
The industry's common practice is to expand and splice multi-DVI output graphics cards before4K processor launched. As shown below：
One of the difficulties of this program is the operation is relatively complex. Sometimes,we need professional graphic cards with integration function to do the integration of patchworks. The other difficulty is sync. Whether it is AMD, NVIDIA's flagship graphics card or a fusion of professional graphics. Multi-DVI output cannot achieve complete sync. Tearing phenomenon will appear in the splicing position.
Fast moving video non-sync: tearing
Then we need professional multi-windows splicer like LVP86XX. The connection is like below. These devices need professional engineers to operate and calculate parameters.
4K processor solution
With 4K processing device, one HMDI or DP port can get the same effect like 4*DVI output expand and splice. The playing operation become very simple at the PC side.VDWALL 4K processor LVP609 can convert 4K signal into several 1920*1080 DVI and output sync. The led display system just use the ordinary sending cards to control. And LVP609 support fast splice function. Entering several parameters can finish splice automatically. No need use expensive and non-zoom 4K sending card. At the same time, processor has many other different inputs. It is convenient to play more materials on the HD LED video wall
4K signal itself difference
On the true and false 4K, 4K TV field was fried for some time. 4K means 3840*2160 or 4096*2160 resolution. It is not 4K signal if the width cannot reach 3840. And it is not called 4K if the height cannot reach 2160. The same 4K signal also has difference,like frame rate is 30Hz or 60Hz. Color space is YUV or RGB and so on.These can bring obvious picture display difference on 4k LED screen.
HDMI 1.4 standard max frame rate is 30Hz means transporting 30Hz picture each second. While HDMI 2.0 is 60Hz means 60Hz picture each second. 60Hz are twice as high as 30Hz. Better quality and detail. The higher the frame rate, the smoother the picture. Intuitive experience can be best reflected.When moving the view quickly, the 60 frames are much smaller than 30 frames.The higher the value, the picture is closer to the real world that the human eye observes.
Color space is also very important parameters. The most widely used is RGB and YUV format. YUV has 4:4:4,4:2:2,4:1:1 and 4:2:0 different sampling format. RGB and YUV 4:4:4 have richer information and better color. While they have high requirements on store space and transmission bandwidth. The other format zoom on color to save bandwidth and store space.
The difficulties of 4K 60Hz processing are large amount of data and high bandwidth. Normal 1920*1080 60Hz point frequency is 148MHz. While 4K 60Hz is 594MHz. 4K 60Hz has high requirements on signal transmission and processing. For the HD LED screen, it also requires the signal transmission and processing cannot be reduced frame. Each DVI output port should be fully sync. So, VDWALL LVP609 is only domestic real 4K 60Hz processor which supports RGB\YUV 4:4:4 format.