The Secret behind Cost Effective AV over IP

The majority of the AV manufacturers have now jumped on the AV over IP bandwagon, Extron being the last of the big ones with the announcement of their NAV series last year. However, the design philosophy and price point varies widely between different manufacturers and technologies. How can certain solutions be purchased at a few hundred dollars, while others cost thousands? Some of this gap is explained by component quality, manufacturing country, and design complexity, but another important factor is the choice of IC (Integrated Circuit), and the codec loaded onto it.

A large number of ASICs. LiveWireInnovation [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)]

When designing AV products, one of the key design choices a manufacturer has to make, is whether basing it on an off-the-shelf chip, a so-called ASIC (Application Specific Integrated Circuit), or use an FPGA (Field Programmable Gate Array). FPGAs are IC's built around a matrix of configurable logic blocks. An FPGA is field programmable, which means it can be reprogrammed and upgraded even after manufacturing. It is, however, useless prior to programming, a complex task requiring experienced developers. The larger Pro AV manufacturers primarily use FPGAs, at least for their core product lines. This allows them to design their own codecs, add functionality through firmware updates, or even switch codecs after the product is launched, as recently done by Crestron when adding the new FlinQ technology from IntoPix to their NVX line. FPGAs are relatively expensive, but since they are generic ICs, they can be purchased in lower volume making them ideal for niche Pro AV product. ASICs are designed for a specific application. They are custom built, and can typically not be altered after production. They are, however, extremely cost effective, often priced at a fraction of an FPGA, but can only be produced in very high quantities, and the initial engineering and production for an FPGA typically starts at around 1 million USD. Using an ASIC also simplifies the development process since the manufacturer won't have to worry about development or sourcing of a codec, and the complex programming of an FPGA.

Aspeed AST1520 4K SoC

Lower cost AV over IP solutions usually use ASICs, and the most popular choice comes from Aspeed Technologies. Aspeed Technologies was founded in 2004, and are headquartered in Hsinchu Science Park, Taiwan. They were honored as one of Forbes Asia's "200 Best Under a Billion” companies in 2014 and 2015 and claim to be "...an innovator of cutting-edge SoC system solutions, which include Server Management SoC solution[s], PC/AV extension solution[s], and Desktop Virtualization solution[s]." In 2017 they had a turnover of 1,89 billion NT$ (61.5 million USD). You may not be familiar with this company, but based on the sheer number of products utilizing this technology, Aspeed is in fact one of the leaders in AV over IP technology. The current top model in their PC/AV Extension range is the AST1520 SoC (System On a Chip), capable of delivering 4K video, multi channel audio and USB 2.0 over standard gigabit Ethernet. AST1520 is using a proprietary codec and is limited to 4K/30 with 4:4:4 chroma sampling (or 4K/60 with 4:2:0 sub sampling). Moreover, it supports video wall functionality and ships complete with firmware including a graphical user interface and a comprehensive API for control and management.

Many of the products leveraging this technology are heavily customized by the product manufacturer with a custom API and management platform, while others ship with the standard firmware from Aspeed, and products from different vendors are in some cases even interoperable. Be aware that certain manufacturers inaccurately market this technology as "their own". Others claim these ASIC based products are using JPEG2000, which is technically incorrect. Since we've already established that JPEG2000 is a bad choice for AV over IP, it's beyond my comprehension why anyone would choose to claim something like that.

I reached out to Aspeed to get their perspective on the the AV over IP market, and what they feel are their biggest benefits over competing technologies:

[...] ASPEED stands out from the competition because we focus on ASICs; we provide SoCs with high quality visually lossless compression, low latency and low cost (vs. FPGA solutions), designed for mature Gigabit networks. [Our solutions also ship with] a complete system firmware [simplifying the design and development process for manufacturers].

When asked about what trends they are seeing, they state that higher resolutions and lowered latency is on their list of requested features along with enhanced switching capabilities and further improvements to the user interface. The big question is when we can expect to see the next generation ASIC with 4K/60 4:4:4 support?

Aspeed confirms they expect to have a 4K/60 ASIC ready by Q4 2019. This will enable AV manufacturers to deliver 4K/60 capable AV over IP products by 2020, at a price point significantly lower than anything on the market today.

Of course, it's not just about the video quality, ASIC based solutions do have their limitations, and isn't necessarily the best choice for Pro AV installations. Since the IC is "hard-coded" it can't be upgraded with support for new features or improvements to the codec, and security flaws may be hard to address. Should an issue arise, it's also more difficult for a manufacturer to debug and analyze the problem, since they have limited control of the chip used. But for residential AV, digital signage applications, the education market or conference room displays, ASIC based solutions might provide the right level of functionality at a very attractive price point.