Dahua Technology full-HD LCD display & control solution

Simplifying the display of multiple cameras from multiple sources has always been a challenge. Early analogue system used multiplexers and matrix switches coupled with many monitors. This created great complexity and cost. Control rooms were very large areas that required many operators. Energy to operate these control rooms was very high. Today, modern technology has enabled the simplification of the control room and the display of video sources along with other vital information.

As the industry migrates from traditional analogue devices to IP network devices, consolidation of equipment is shrinking the space requirement for control rooms. The use of TCP/IP connectivity is enabling the linking of information systems such as weather, traffic, and other agency data along with the video feeds. New display technology now allows multiple images to be put together on a single display or span many displays. Content can now be dynamically assigned and moved throughout the control room display wall. LED monitors are now more energy efficient and are more durable when viewing 24/7 without the common “burn-in” issues.  

As a total solution provider, Dahua Technology provides front-end cameras, NVRs, DVRs, as well as complete control centre solutions.

Splicing video wall

Dahua has been a manufacturer of video wall solutions since 2007. Dahua is one of the largest splicing video wall providers in China. Dahua ranked second with 9.1% market share in the industry. 

Splicing video walls normally use LCD screens (LED backlight) with a very slim physical bezel, which is quite important when displaying an image across several monitors. The most common bezel in the market is around 5.5 millimetres. Dahua is proud to offer industry leading bezel sizes from 3.5mm. Dahua video wall monitors are available in 46” and 55” panel sizes. The displays have brightness levels from 500 nits to 700 nits to ensure a good view in all ambient light settings. All of the display panels are designed for 24/7 operation. 

The surveillance industry requirement for video splicing walls far exceeds the requirements of digital signage applications. The surveillance application requires many types of inputs from devices including: IPCs, DVRs, NVRs; local HDMI/DVI/VGA video signals; and the number of the channels are often above 200. The ability to view many inputs with a single output or arrange inputs and outputs to meet the specific requirement can be challenging. 

Network video matrix – a video wall controller that fits all scenarios

In order to meet those tough requirements, Dahua utilises its experience of network video encoding and decoding technology in video matrix development. There are several technologies of video wall display in the market currently.  

One way is using PC-based or server-based hardware to extend some graphics cards and develop software to control the output of the graphics card (It is called “virtual matrix” by some VMS vendors). Virtual matrix switches have specific disadvantages. Operating System vulnerabilities, graphic card limitations, and limited scalability make this solution less than optimal. 

Dahua network video matrix is an embedded hardware specially designed for video wall solutions. Based on Advanced Telecom Computing Architecture (ATCA) architecture, it offers a redundant design for many important parts, such as fans and power, which greatly enhance its reliability and stability. In order to lengthen service life and make repair easy, modular design is used . The matrix consists of 3 parts: mainframe, encoding card and decoding card. The mainframe offers power, control, network and high bandwidth backplane for different cards. For the encoding card, the company offers multiple kinds of video interfaces including HDMI/ DVI/ VGA/ HDSDI/ HDCVI/ CVBS, etc. It is easy to input any kind of supported signal to this matrix with just the selection of the corresponding encoding card. Besides all these local video signals, it has a great capacity for network video streams such as IPCs, NVRs DVRs, etc. For the decoding card, it provides high network video decoding ability and offers the video output channel for both network video and local video signal as well. For pure network application, one matrix can decode 160ch@1080P/ 640ch@D1 network video streams and support up to 40 screens. 

Combine this network video matrix with the video wall to provide a perfect solution for centralised visualisation in surveillance applications. 

Another interesting trend

In splicing video wall applications, LCD and DLP technology is already mature and be widely used in the market for several years. However, the LED modular technology comes into this market, growing with increasing share. DLP use has dropped with the trend towards LCD and LED Modules. The smaller pixel pitch of LED Modules is leading to higher adoption for indoor use. LED Modules have compelling advantages including: No physical seams, 281 trillion gorgeous colour, high brightness, high refresh frequency, long lifespan, and easy maintenance. Dahua believes that with the costs reduced, LED Modules will become a new driving force in video wall applications.  

LED Modules are being used today for many indoor applications including: performance venues, advertising, information display, and promotional video. Hybrid systems of LED Modules and LCD Displays are being used more frequently in surveillance control room applications.