RGBLink Has a Unique 8K Scaler
We recently reported on a new video scaler system for professional A/V applications from RGBLink, so we contacted the firm to find out more and caught up with Product Marketing Manager, Justin Knox, on a video call.
First, we asked about the company. The full company name is Xiamen RGBlink Science & Technology Co Ltd, which clarifies that the company is based in China and Knox told us that it is fifteen years old. Part of the company’s success has been the result of its proximity to a lot of FPGA (Field Programmable Gate Array) developers in China and Taiwan as much of the company’s added value is in developing ASICs based on the technology.
Broadcasters are among the major customers for the firm and the use of FPGAs provides extremely fast processing allowing the delivery of very low latency solutions – a critical aspect for those companies. Having said that, Knox told us that earlier the firm’s main market was the A/V rental area. The firm made a range of switching and scaling solutions including controllers for video walls and LED displays but, after Covid, as he put it “everyone became a broadcaster”.
The New Scaler
A key turning point for RGBLink in developing the D8 and then the D8 Plus scaler, was the availability of the Apple Mac Studio system based on the M2 Max chip and which enabled 8K 30P output and later 8K 60P over HDMI. As Knox pointed out, prior to that there were plenty of 8K cameras, but how would you process and display the content? Without the processors, archiving was also a challenge and that is important in live productions. Now, since Apple’s launch, X86-based systems are also available based on AMD and Nvidia cards that can support 8K output.
The D8 boxes are designed to process inputs from HDMI at up to 8K (in 4:4:4 at 30P and 4:2:0 at 60P) and support a wide variety of different outputs. At a simple level, the processor can accept an 8K input and split it into four outputs to 4K UltraHD displays. The Plus model also supports a DP 1.4 input for up to 8K in addition to the HDMI connection and Knox told us that he believes the unit is the first in the market to support simultaneous use of both of those inputs. The D8 units can support ‘unequal splicing’ with different sized displays as well as vertical and horizontal arrangements.
Other vendors have told us in the past that broadcasters often like to use a single high resolution 8K surface to hold all the video for different displays around a studio, with each of the displays acting as a ‘window’ onto that surface. The RGBLink D8 can also downscale to suit different display resolutions. The processors can make it relatively simple to merge and re-sync different signal sources to ensure tear-free final display. Using FPGAs avoids the kind of latency that might be present in GPU-based solutions. RGBLink has its own designs and in-house expertise for this kind of processing and to support low noise switching.
In terms of latency, Knox told us that typical cross conversion of different formats typically takes less than a single frame, while scaling would take ‘a couple of frames’. He also told us that in practice, the firm has found quite a lot of detailed variation in 8K 60P signals from different devices and different equipment makers.
The widest adoption so far of the D8 processors has been in the rapidly developing world of immersive and projected environments. Although LED walls in high resolution are getting more popular, but the cost can be prohibitive. LCD video walls remain popular, partly because integrators are comfortable with how to support and install them.
