With the rapid development of network and codec technology, in order to better meet the command center, data center and other large-scale comprehensive audio and video solutions
The demand of solution interconnection, distributed system arises.
LED has great advantages due to its seamless stitching, flexible size layout, and excellent color display in distributed display applications.
So why the traditional distributed system will appear these problems, and Nova [heavenly power distributed system] through what efforts, to fully give play to the display advantages of LED, to achieve the most understanding of LED distributed.
Traditional distributed system
At present, the popular distributed system in the market mainly adopts the standard H264 / H265 deep compression algorithm to compress the first HD video signal into the road network signal. Although the high compression ratio greatly reduces the requirement of transmission bandwidth, the disadvantages are also very obvious.
Disadvantages: ①: low quality compression leads to large picture quality loss
The compression ratio of the standard deep compression algorithm can reach 50-300 times, and the high compression ratio must bring a loss of picture quality. The traditional distribution usually only supports 8bi t 4:2 ∶ 0 processing, resulting in the insufficient color expression of the overall distributed system, especially in the text images and different background colors, for the display
Disadvantages. ②: shows a large latency
H.264/H.265 The inter frame compression algorithm introduces a display delay of 2-3 frames in both decoding and encoding. In addition to the influence of the transmission protocol, image processing and other parts, the delay of some products even exceeds 120ms, and there is an obvious delay and lag feeling, which seriously reduces the user's operation experience.
Disadvantages ③: splicing large screen synchronization is poor, strong tear sense
The traditional distributed synchronization accuracy is low, the inter-node deviation is generally at the hundreds of us or even ms level, and the synchronization state is not stable enough, resulting in the uncertain screen will be
The tearing phenomenon, not only visible to the naked eye, but more obvious when taking photos, seriously affects the display effect of LED screen.
Disadvantages ④: Only the standard resolution is supported
Because of its modular and arbitrary splicing characteristics, LED often has a variety of special non-standard resolutions. And the traditional distributed display is mostly used in liquid crystal display
Here, by only supporting regular standard resolutions, such as 1920 * 1080,2048 * 1536, they are not friendly enough to support for the special and flexible resolution of LED. In making
There may be proportional distortion and other conditions, and even need multiple splicing, which not only increases the customer cost, but also greatly affects the user experience.
[Tianquan Distributed System] adopts HEVC Plus compression algorithm, combined with 10bit 4 ∶ 4, full link 4K@60Hz, nanosecond synchronization, and display from
Define and other finishing functions, maintain low bandwidth while retaining more details, from the picture quality, synchronization, delay and rest test, smoothness and other dimensions, fully send
Swing out the display advantage of the LED.
10bit 4:4:4 native picture quality is lifelike
Nova NSMC intelligent image encoding technology, combined with a unique hardware platform, fully match the HFR codec, can support up to 120Hz refresh rate, Capture and display of high-speed video is clearer. At the same time, NSMC supports 10bit 4 : 4 processing, emphasizing Smart Detect, through computer vision
Detection, histogram comparison and edge recognition algorithm, the intelligent distinction between the natural scene and the text scene, the adaptive adjustment of the codec algorithm, with a needle
The sexual image compression, decompression, so that the color reduction is more real and accurate, the gray scale gradually change and smooth, fundamentally support BT2020, really match With LED display features, to achieve HDR.
Traditional word processing
NMSC word processing
After the Nova NSMC intelligent image coding technology processing text: chroma information remains intact; Accurately restore the font lines, effectively avoid the text color blur and stroke loss, especially the fault of the slash line
Traditional natural image processing
NMSC natural image processing
Natural scenes processed by Nova NSMC intelligent image coding technology:
image texture information display is complete, effectively reduce edge jagged sense, transition, smooth, exquisite effect.
Full link 4K@60Hz shows smooth jam
Traditional distributed video refresh rate can only do 30Hz processing, and distributed using HFR (high-frame rate) high frame rate technology, breakthrough video refresh rate to 60Hz, and from the input collection, decoding output, support full link 4K@60Hz, some scenarios refresh rate can reach 120Hz, as low as 60ms delay, solve the drag, delay, etc.60FPS
Net Sync + Nova Sync nanosecond level Sync
Based on the Net network synchronization protocol and combined with the unique Nova Sync hardware synchronization technology of Nova, the Tianquan distributed system realizes the accurate synchronization of the system output clock, and can still maintain a good synchronization state for a long time, even comparable to the synchronization of centralized devices. Real nanosecond level synchronization that can withstand the double test of the naked eye and the camera
NMSC natural image processing
In addition to the LED display, Tianquan also supports projection, LCD and other full-class display media. And support a fully custom resolution (limit width, high 819 2), to meet the needs of some ultra-wide, ultra-high screen body display requirements. In addition, synchronous splicing can also be achieved in multiple screens with different width and height proportions, which solves the problem that other multiple systems can not customize the resolution, leading to poor practicality.
NMSC natural image processing
In the command center, data center and other distributed system is becoming more and more widely used today, diversified display demand, nova power distributed system can better match LED screen flexible, stable, simple operation, and many other practical requirements, and ensure the high picture quality display, is the most suitable for large-scale audio and video demand, the most understand LED distributed solutions.
Post time: Nov-24-2022
