SAFE FLEET BLOG

On-board video technology is in the midst of an important transition in image quality, or what I like to call a ‘resolution evolution.’ The introduction of the Network Video Recorder (NVR) into the fixed surveillance market several years ago, brought with it the promise of higher quality images, as well as remote configuration, camera re-booting and monitoring. High-definition cameras and recorders were on the hot list for many transit agencies looking to upgrade their existing vehicle camera systems, with improvements in resolution driving the desire for change.

What many have discovered while implementing NVRs and IP-based systems in a mobile environment, is that there are different challenges with respect to video storage time, existing camera return on investment (ROI), ease of installation, maintenance, and both general networking and IT expertise, that need consideration. This has led to the introduction of hybrid systems capable of recording both analog and high-definition cameras.  These systems seem to offer a good blend of resolution improvements, reduced installation complexity, and extended analog camera ROI.

DVR vs. NVR vs. Hybrid

The ‘brains’ of a mobile surveillance system is the video recorder. Traditionally this was a digital video recorder or DVR, which supported low-to-medium-resolution analog cameras, converting analog camera feeds into a digital format for viewing and recording.

A Network Video Recorder (NVR) was the next evolution that allowed for the use of IP cameras that delivered a high-definition image directly to the recorder without requiring conversion. Although these new systems offered higher resolutions, they also had the added complexity of IP networking, programming, and required a complete replacement of existing cameras and cabling.

New hybrid DVRs were introduced to offer the advantages of supporting high-definition cameras, while extending the life of existing analog cameras, as well as increasing ROI. Newer versions of the hybrid, such as Seon’s recent introduction of the NH16 and DH6, give further flexibility by offering any combination of analog and HD cameras capable of plugging into any DVR port without complicated programming.

IP or HD:  Is there a difference?

The terms IP and HD are often used interchangeably, but are they really the same thing?  All IP cameras are high definition, however not all high-definition cameras are IP. Some hybrid systems support analog high definition technology (AHD) which can deliver the same resolution as IP cameras, but don’t require the complicated programming or specialized installation. This can be a benefit and save significant dollars in a large scale retro-fit project as you don’t need specific computer networking expertise to install and maintain your camera system.  If you decide to go all IP, it’s a good idea to have IT people on staff that are well-versed in IP networks.

Maintain video retention times

One important consideration in choosing whether to go hybrid vs. NVR are the requirements for video retention.  While high-definition cameras improve image clarity, they also increase storage requirements.  Footage from a 720p HD camera can take up three times the storage of a medium resolution analog camera feed.  Multiply this by 16 cameras and your storage capacity requirements grow and video retention times decline. Many transit agencies require up to 30 days storage on the recorder before being overwritten. With hybrid systems you have the flexibility to use a mix of analog and HD cameras so you get the benefits of high resolution in key areas, such as the fare box, windshield and outdoor cameras, while not having to sacrifice desired video retention timeframes.

Cost impacts

Hybrid systems not only offer the flexibility to choose the pace of your video upgrade program, they also provide some additional cost savings over NVRs. This is most significant in scenarios where agencies are replacing a fleet of buses with existing analog camera systems.  Hybrids allow you to maintain your existing analog cameras, extending your ROI and decreasing the overall cost of the system.

We’ve almost come full circle

Although the introduction of NVRs brought with them the promise of new, higher quality images and simplified network infrastructure across the entire transit IT system, they also created additional complexity and costs that new technology initially brings.  The introduction of hybrids are proving to be a good balance of adding future-thinking technology while not having to sacrifice your investment in existing video components.

One size definitely does not fit all when it comes to technology. Choose a vendor partner that offers a number of scalable solutions and is willing to work with you to explore the best fit.