What is AVLC?
What is AVLC?
AVLC – or Adaptive Visual Lossless Compression is a new technology that can deliver genuine 4K UHD signals in perfect quality up to 70m over a single run of Cat5e/6/7 cable.
Why do we need AVLC?
HDBaseT can comfortably transmit timings that fall under the 10.2 Gigabits per second constraint which in the world of AV can pose a problem to today’s installer and AV integrator. This is because certain timings such as 4K@60hz, 444, 8bit which comes in at around 17.8Gigabits per second will not be able to be transmitted without applying a simple 420 colour space conversion (CSC) which basically can half the band width. More common technologies such as SKYQ can output content at 4KUHD@50hz, 420, 10bit Deep colour and the most used HDR10 timing which is 4K@24hz, 444, 10bit Deep Colour and both these outputs come in at around 11.16Gigabits per second which is over the 10.2Gigabits per second limitation.
This presents a problem when distributing these sorts of signals over long distances and into multiple zones, specifically over technologies such as; HDBaseT and most AV over IP systems. So HDBaseT and manufacturers have suggested a way around these bandwidth issues by introducing technologies such as, DSC (display stream compression) and AVLC (adaptive visual lossless compression).
How does AVLC and DSC work?
These work by providing a visually lossless experience when dealing with technologies again such as HDR10, Dolbyvison, SkyQ@10bit and even still accommodating for Higher frame rate 4K outputting at 444 60hz.
These technologies are adaptive in a way that it can apply CSC (colour space conversion) where necessary and/or through a line by line compression method with the ability to output at a limited latency and with no visual loss of picture quality.
What to look out for:
If you’re looking to distribute all the aforementioned signals, only AVLC which is available today and/or DSC technologies for the future will be able to achieve these higher data rates specifically over HDBaseT. So make sure you ask your suppliers that the kit that you specify can actually distribute HDR10, Dolbyvision, High Frame Rate 4K@60hz 444 or even SkyQ@10bit and do not be fooled by distorted messaging such as, HDR ready, HDR pass-thru or even 4KHDR@24 420, because simply this will lead to disappointment and your picture quality will be compromised at the receiver stage of your system.
