| The choice between PC-based and embedded digital video recorders is often more difficult than it looks. Traditionally, embedded DVRs utilize an operating system that is booted from memory, not from a hard drive. These machines do not have as many features as PC-based products, are not upgradeable and have limited storage capacity. While embedded DVRs are usually easier to use and have fewer features than their PC-based counterparts, the features they lack are not always Necessary. What should the selection criteria be between the two units? To a large extent, it’s how you think about DVRs that gives the greatest insight.
If you have a “set it and forget it” mentality, and aren’t looking to expand, an embedded DVR is usually the best choice. Embedded DVRs are smaller than PC-based units, cost less and perform surprisingly well since their operating system — usually Linux — is often “tweaked” for performance with that exact hardware. While this often limits expandability, this limitation is not a factor for the type of user looking to reliably record video and only review it if there’s an incident.
On the other hand, if you’re looking for your DVR to be an active part of your surveillance team, a PC-based unit may be a better choice. It will have advanced search capabilities that allow such luxuries as search on direction, speed, loss or presence of something in a scene.
While either type of system can be upgraded, the PC-based system is generally easier to upgrade. PC-based units also have more options than embedded units, such as the ability to scale video resolution and frame rate on a channel-by-channel basis. Since there are numerous PC-based processors on which manufacturers can build their units, PC-based DVRs can be found with higher frame rates （the amount of video images they can process each second） than their embedded counterparts.
It is also easier to upgrade PCs strictly on the basis of adding more hardware- and software-based features. Embedded units tend to get upgrades to fix bugs or add minor features that were promised but left out of their initial release.
A PC-based unit is often used as part of a bigger system. For example, PC-based units are more likely to be integrated with access control or enterprise-wide point-of-sale systems and frequently have companion software interfaces to allow other manufacturers to write software that talks to them. This capability is extremely rare among embedded units.
The remote client interface is another factor. It is becoming more common for DVRs to be located in a remote area with the primary interface being browser-based or proprietary remote software. While either type of unit should have similar technical capabilities when interfaced remoy, the PC-based units generally have more sophisticated clients because of the perceived market positioning. Again, look to see if these advanced features will ever be used to help with the buying decision. If the ability to look at multiple DVRs simultaneously from a single Web page is important, you can only find that feature on a PC-based unit.
Finally, we can’t ignore the pricing differential — in both hard and soft dollars. Embedded DVRs are usually much less expensive than PC-based machines. But, an embedded unit contains only the components needed to do the job at hand — it wasn’t built on a platform that was also designed to handle business tasks or play state-of-the-art computer games.
On the soft-dollar side, embedded units usually require a trip to the machine to handle software upgrades when needed, while PC-based machines can often be upgraded across a network. This can eat up some of the hard-cost savings, particularly if you’re doing a large rollout over an extended period and want to keep your software versions consistent across all machines.
No Easy Answers
The fact that there are no clear-cut answers as to which unit is best can be attributed to the sheer variety of DVRs on the market, and the ever-expanding capabilities that come from advancements in technology.
While this article may give you some ideas to point you in the right direction, I’m a big believer in looking beyond the spec sheet.
The best unit in the world will quickly become a doorstop if you don’t get the support you need to keep it running. |
