More real-life cases needed for HD-SDI
a&s International | Date:
Standardization is a deciding factor for a product to be widely adopted. Although it may be harsh to ask a new ecosystem to immediately produce universally usable standards, it is nonetheless a problem HD-SDI must resolve.
It is not just a matter of standardizing cameras, said Zhou Sheng Qiang, GM of Video Surveillance at Keda Technology. "First on the list is cabling. Although HD-SDI can utilize existing coaxial cables, not any cable can transmit high-quality images. A certain quality must be met for both the cables and the installation of them. Next, we can look at the TV wall; even connectors to the displays are not necessarily compatible with HD-SDI. Interoperability between devices made by different manufacturers, such as HD-SDI encoders and DVRs, still has problems. Multiple points of failure from the front end to back result in instability of the system."
The quest for universal standards is still ongoing. In the mean time, end users and SIs will prefer more stable and mature solutions. HD-SDI will need to catch up in the standardization space and manufacturers roll out complete solutions, from front end to back, to become a true alternative in the HD arena.
Chips: Not Competitive
The aforementioned points are why HD IP-based video surveillance manufacturers doubt HD-SDI will become a competing faction in the market.
However some chipmakers, such as Ambarella, are leaning toward HD-SDI products. Asked whether HD-SDI will affect large chip vendors' attitude toward IP, Zhou said, "Network cameras contain chips that digitize, process and compress images, but that does not mean HD-SDI is more competitive because it has no need for these chips."
Another way of looking at it, Zhou continued, is that "Video processing chips are a plus for network cameras, since it means that the camera is more intelligent and is capable of much more than just capturing video. The feats it can accomplish will only increase as time goes on."
When HD-SDI advocates claimed the dawn of a "zero latency, zero compression" age for video surveillance, users frustrated with latency in IP-based systems sighed with relief as they hoped HD-SDI could solve all the problems they faced.
Settings where low latency is critical and have short distances and few locations to cover do indeed see HD-SDI making much more sense than IP-based systems. Applications like gaming, traffic monitoring, financial institutes, operating tables and safe city initiatives all see the value in HD-SDI and will benefit from its pros.
On the other hand, in a trend of globalization, digitization and connectivity, HD network cameras are a more logical direction to move in.
Although HD-SDI solves the HD equation for analog video surveillance, the fact that it is still a closed system results in complex cabling and mundane installation. Furthermore, HD-SDI maxes out at 2 megapixels or 1,080p. These are both limitations that hinder its practicality in the big wave of digitization and increased connectivity.
Regarding other limitations, said Zeng Chun Wei of Poseidon Technology, "HD-SDI features much better image quality over traditional analog systems, but it also inherits the same downsides. “One issue is scalability. HD-SDI uses DVRs, which limit the front-end devices.” "Another is cost. Although it allows the reuse of existing cables, additional cash has to be coughed up to replace front-end devices, optical transceivers and back-end recorders. At the moment, these are still fairly expensive."
HD-SDI does indeed have its place in the market, but it will not become a strong competitor to IP-based video surveillance; HD IP-based video allows better integration, interoperability and flexibility, according to Zeng. "IP-based video surveillance will represent a large portion of the customer base, while HD-SDI will remain a better option for niche markets. If HD-SDI cannot achieve economy of scale, HD via IP will still make more sense in most settings."
Product Adopted:Network Cameras
Two competing and complementing technologies are good for the industry because manufacturers on both sides are creating more options and better products for their customers, Zhou said. "HD-SDI complements IP-based systems, as both are ways to sell HD to the end user. It reaffirms the notion that HD video surveillance is indeed in high demand, which is also a huge opportunity for the IP people."