New technologies are making it more cost-effective than ever for businesses to add or upgrade to digital video surveillance for their security systems. For many businesses today, the extra benefits of digital video surveillance -- including easier installation, remote monitoring, cloud storage and accessibility of video footage, and far better image quality -- make them a very attractive choice. But does that mean that analog systems are obsolete?
Analog systems are certainly not obsolete. On the contrary, the technology for analog systems was available long before digital systems. As a result, many businesses have already invested in them, and their use is still growing. However, with the additional capabilities of digital or Internet Protocol (IP) – systems, their use is projected to grow twice as fast as analog systems over the next five years.
So, how do you determine which type of video surveillance system is best for your business? This post will help you do that by equipping you with a basic understanding of the different components of video surveillance systems and the most important factors you need to consider when choosing one.
Video Cameras and Recording Devices
The most basic video surveillance systems include one or more security cameras strategically placed to monitor for motion and activity in the area(s) within or around your building that you want to protect. There are two main types of cameras used in video surveillance systems -- analog cameras and IP cameras. Both capture and transmit data in different ways, and both require different types of recording systems.
All video cameras capture video as a series of individual images. The recording system records the video in digital format through the process of encoding (commonly called video processing), which compresses all the individual images captured by the camera into a single, fluid video file. Once encoded, the video file can be physically transferred or transmitted through a network to some type of storage such as a separate hard drive, a memory card, a USB device, or the cloud.
Analog Cameras and Digital Video Recorders (DVR)
Analog cameras require a digital video recorder (DVR) because they cannot process video. Instead, the camera captures and streams the video footage -- all those individual images -- as analog signals through a coaxial cable to the DVR, which encodes it for storage.
IP Cameras and Network Video Recorders (NVR)
Unlike analog cameras, IP cameras capture data in digital format. Therefore, IP cameras require a network video recorder (NVR), which only works with digital footage. With IP cameras, the video is encoded at the camera and then streamed to the NVR. Therefore, this type of system uses the NVR for storage and remote viewing, not processing.
The video can be streamed from the camera to the NVR through either an Ethernet cable or via a wireless connection (wifi), allowing both wired or wireless options.
Hybrid Video Recorders (HVR)
Today, hybrid video recorders (HVRs) are available on the market, making it possible to combine analog and IP cameras into one video surveillance system. With an HVR, the video from analog cameras is transmitted over coaxial cables to the HVR, while the video from IP cameras is transmitted over Ethernet cables or wifi to the HVR.
Choosing Between Analog and IP
There are many features you might consider when choosing between analog and IP systems -- too many to cover in a single post. However, three of the most important are video quality, storage, and cost.
Video Quality Considerations
Video quality is determined by your video camera and is affected by several factors:
Resolution -- Resolution refers to the number of pixels the camera can capture, measured in terms of the image width and height. The table below illustrates the differences between analog and IP cameras regarding their resolution and the relative sizes of the images they capture. While the resolution isn't the only factor determining video quality, generally speaking, the higher the resolution, the higher the image quality and the larger the video file will be too, which means more storage will be required.
|
Resolution |
Image Size in Pixels (horizontal x vertical) |
Pixels in each still image |
|
Analog Security Cameras (measured as the number of horizontal and vertical lines in pixels) |
||
|
720p AHD |
1280x720 |
921,600 |
|
1080p AHD |
1920x1080 |
2,073,600 |
|
IP Security Cameras (measured in pixels) |
||
|
2 MP (1080p) |
1920x1080 |
2,073,600 |
|
4 MP (1440p) |
2560x1440 |
3,686,400 |
|
5 MP (1920p) |
2560x1920 |
5,017,600 |
Focal Length -- The focal length of the camera lens determines how wide the viewing angle is. This may be an important consideration depending on the area you need your camera to cover. The longer the focal length of the camera, the wider an area it can cover. However, with a longer focal length camera, you will sacrifice some detail over a distance. So, you need to evaluate the camera's focal length based on the area you're trying to secure. For example, you might need a mix of cameras with different focal lengths to cover a parking lot, whereas you could probably go with either a long or short focal length camera to cover an entryway.
Image Sensor Size -- The image sensor in a camera allows the camera to convert light into a digital image. The larger the image sensor, the wider the field of view and greater detail in the captured images.
Frame Rate -- Your camera's frame rate refers to how many individual images it can capture each second. Because they capture more images, cameras with higher frame rates produce videos with more detail and less choppiness. The frame rates of analog cameras are typically lower than those available with IP cameras.
Video Storage Considerations
Storage is always an important factor to consider regardless of the type of video surveillance system you choose. This is because video surveillance systems capture a large amount of video as they are usually used around the clock.
Take another look at the table above, paying particular attention to the number of pixels that just one image produces. Multiply that by thousands of images, and you end up with enormous data files. If you're using analog cameras, you can use digital storage devices such as hard drives, memory cards, or USB devices. However, this can add to your equipment costs as you'll probably have to invest in quite a few to ensure enough space for your files. IP cameras capture video at a higher resolution than analog cameras and, as a result, produce much larger video files. If you're planning to use IP cameras, you will probably need to consider cloud storage.
There are a number of video storage calculators online that can help you determine your storage needs. Ultimately, the best type of storage and how much you need will depend on how many cameras you have in your system and how you plan to manage your recordings. Developing an archival process and a retention policy that, based on the needs of your business, specifies how long you will keep your recordings will help you keep your storage costs in check.
Equipment and Installation Costs
While IP cameras are more expensive than analog cameras, the overall cost of an IP system is usually lower than that of an analog system. This is because analog systems usually require more cameras and far more complex wiring than IP systems, which drives up the installation costs.
If you are considering upgrading an analog system, a hybrid system might be a good option as it would allow you to spread the costs of new IP cameras out over time instead of replacing them all at once.
Koorsen Can Help You Find the Perfect System for Your Business
Koorsen Fire & Security is a leader in designing, engineering, installing, and maintaining integrated security solutions. Whether upgrading an existing video surveillance system or installing a new one, our security professionals will work with you to develop a customized and comprehensive plan that meets your business's needs and budget. Contact the security solutions experts at Koorsen Fire & Security today to get started.
