DVRs make it possible for users to convert analog CCTV video to digital, allowing for remote monitoring, greater storage capacity, and quick and easy searches. Think of the DVR as a cost-effective solution for those not yet ready to move to a full-on IP surveillance setup. Digital video recorders allow you to bring your analog CCTV cameras into the modern age. When footage is converted to digital, new worlds open up in terms of how you can view and manage your video feeds.
It wasn't long ago that most surveillance systems used VCRs to record individual video streams. The footage was recorded either continuously or triggered by an event, and recorded on cassette tape usually at a rate of 25 frames per second. Back in the day, this seemed like an advanced solution. But now we know, regardless of what type of surveillance cameras you're using, storing video footage on cassette tapes is not a very effective strategy. The tapes take up space, can't hold very much information, and they're incredibly difficult to search through if you need to pinpoint video images of a specific event.
Enter the digital video recorder (DVR).
What is a Digital Video Recorder?
A Digital Video Recorder (DVR) contains software, video storage, and a computer hard disk all in a single unit. The DVR accepts analog video feeds and converts them to digital. It's a cost-effective way to bring an analog CCTV system into the modern world, and provides some of the same benefits as IP video, but in a more budget-friendly solution.
Benefits of DVR Recording
DVR recording is a great way to migrate your analog CCTV into a digital surveillance solution. This is a low-cost option that brings a number of benefits to those who already own analog cameras, or aren't yet ready to make the move to a fully IP-based surveillance system.
In the past, conventional CCTV systems could only transmit video to a single monitoring station, but that's not the case when you're using a DVR. Most digital video recorders now allow you to access your camera footage remotely over the internet. By connecting your analog cameras to a DVR, you can monitor video feeds in real time from any computer with internet access, and even from compatible cell phones or handheld PDAs.
Not long ago, most surveillance systems could only record to VHS cassette tape. Recording to tape has many drawbacks. For one, the tapes are bulky and take up a lot of space. Additionally, trying to search the recorded footage on analog tape can be a time-wasting nightmare. With DVRs, your footage is converted from analog to digital, so you can store significantly more video without the clutter, and it's much faster and easier to sort through archived footage.
To make the most of available storage capacity, DVRs provide a number of different compression technologies. Common compression formats include Motion JPEG, MPEG-4, and H.264. With video compression, your files sizes are reduced as much as possible without compromising image quality.
Most digital video recorders offer password protection so only authorized users are able to access the video footage from remote locations.
Converting from Analog to IP Surveillance
It's no secret that the future of video surveillance is in IP-based solutions, but that doesn't mean you need to throw out your existing analog cameras as you make the transition. Cutting-edge surveillance equipment such as hybrid DVRs and video encoders allow you to build a future-proof IP surveillance network while retaining the analog security cameras you already have on hand.
Hybrid Analog/IP Systems
There's a difference between a DVR-based system and a hybrid surveillance system. With a standard DVR setup, you're limited to using only CCTV cameras. The analog video signals are sent to a DVR where the footage is then converted to digital. In a hybrid system, you have the option of using both IP network cameras and analog cameras, all operating together on the same network. This is typically done by using video encoders and servers, or a hybrid DVR.
Video Encoders & Servers
A video encoder (also know as a server) digitizes analog video signals so they can be sent directly over an IP network. This enables users to view live video images using a standard web browser or with video management software on any local or remote computer with network access. Best of all, the digitized footage from the analog cameras is traveling along the same IP network as any new IP cameras you add, so you can view footage from all your cameras the same way.
Hybrid DVRs are unique in that they can support both analog CCTV cameras and IP network cameras. This level of flexibility isn't available with traditional DVRs, which only connect to analog cameras. Hybrid DVRs ease the transition from analog to IP surveillance. Since they support both camera types, you don't have to restrict your camera options. This makes it easy to move towards an IP-based solution while still using lower-cost analog cameras when necessary.