IP Cameras Versus Analog Cameras
From EZWatch Wiki
At this time, there are two major types of cameras available : IP network cameras, and Analog cameras. Both use Digital Circuits to 'see' and send the information back to a recorder, but each one sends the data in a different way. They both have major strengths and some limitations that make them ideal for a huge variety of situations. This guide will help explain the major differences, and help you to determine what camera would work best for you.
Analog Video Cameras
An analog signal is a constant stream of data being transmitted from the camera to the recorder. The data flows in one direction ONLY (Meaning the camera constantly transmits and never receives information from the recorder). This means that the refresh rate is very fluid and very smooth, but outside interference (or 'noise') which affects the signal will show up as distortion on the screen. Because the data never stops, only a single signal can be present on any particular line.
The biggest and most important advantage that this presents is the framerate of the camera being a steady 30 FPS. Having a high framerate is extremely vital when trying to capture high detail - subtle movements that can be missed may mean the difference between a pocketed $20 bill versus a $20 bill that ends up in a cash register. It's also very important for high-speed, such as a vehicle moving quickly through a frame.
Perhaps the biggest drawback to analog cameras is the wiring that is required. Each camera requires its own connection to the system, and while that may not be significant for home and small office kits, some of the larger camera systems can have up to 48 individual cables running to the back of the PC. This has the disadvantage of being somewhat messy looking (and very ugly if the PC-DVR is set up in an office), and being far more difficult for the initial installation.
Wireless analog cameras are an unpopular choice for several reasons. The signal being transmitted is not very secure, anyone with the right equipment can 'tap in' and see the camera view. The unit is very susceptible to interference; while it will maintain a high refresh rate despite large interference, the image quality will degrade rapidly and you will see more static/snow, wavy lines through the image, or even a bouncing/rolling image depending on how much interference it is receiving.
The DVR itself handles all functions of the camera, from the live view, to the recording, to the ability to view it remotely and the ability to notify you if an event occurs. The camera does nothing but transmit the video signal.
IP Video Signal Explained
The digital signal used by IP cameras is video that has been broken down into extremely small packets of information. Each packet is sent separately, and the camera will listen to see if the packets arrive successfully and undamaged. This means that if a packet arrives lost or damaged due to signal interference, it will be re-sent until it arrives intact. This allows the camera to maintain an extremely high-quality, very crisp and clear image despite any amount of interference or transmission difficulty. On the other hand it also means that interference or lost data will slow down the framerate of the camera, providing a more jumpy, jerky image with more noticable gaps in the motion.
IP cameras are known for their incredible level of quality. Since the video is not affected by outside interference, the camera can broadcast a high-quality, high-detail signal in any conditions. This makes the unit perfect for applications where extremely high detail is essential, but where you can get by without needing to worry as much about capturing motion (Entrances/Exits where a person's face can be caught in extremely high detail, for example).
The other major advantage of the IP cameras is that only a single cable, a network cable, needs to be run to the DVR. This makes for an extremely clean installation, even when many cameras are connected. Each camera needs a connection to the home/business network, and depending upon the network layout (Hubs, switches, routers, etc.) the wiring can be streamlined to ensure a rapid, clean installation. In many newer homes and offices, network ports are pre-wired and available for an even faster setup.
The biggest downfall of Wireless cameras is that the units have a much lower framerate than analog cameras. The IP cameras can never maintain the same incredibly smooth framerate that an Analog camera can. When converting the video to packets, sending them across the network, then decoding them and assembling them back into a video signal, there is a certain amount of latency (delay). This delay can be extremely minor or it can be quite severe, but it is always present. The delay gets larger if you have many other people using your computer network for other things, if there are many cameras present on the network, or if you are watching the cameras over a slower type of connection (Such as over the Internet). All of these can slow down the refresh rate and produce larger gaps between the images.
Wireless IP cameras tend to be a much more popular wireless solution than wireless analog cameras. Outside interference is always a large factor with wireless cameras; there's no way to shield the signal like you can with a hardwired camera. The interference does not actually degrade the quality of the image, but both can and likely WILL slow down the framerate for packets that are lost or corrupted due to interference. They are also popular because of the ease of integration - a wireless IP camera can connect to any standard 802.11 wireless network, and new routers and products make setting up a wireless network is easier than ever.
An IP camera tends to be slightly less secure than an analog camera by default; since it is on a network (Or accessible via the internet) this presents the possibility that many more people could have access to it than an Analog Camera, which can only be seen by the DVR it's connected to. To combat this security issue, IP cameras have the ability to 'encrypt' the signal, to make it unreadable by an unauthorized source. This encryption can be used with both Wired and Wireless cameras to ensure that no unauthorized persons can view the video.
The camera can be accessed directly without even needing the DVR at all simply by accessing the address of the camera from a web browser, however depending upon the camera you may lack some or all features that the DVR itself would provide. Most IP cameras are able to be viewed from the browser, but require the DVR to actually record or sense motion. In nearly every case, the camera is accessed directly during the initial connection and setup, and is accessed by the DVR software once the camera is online.
Both Analog and IP cameras provide their own benefits but also have their own limitations. Each has its own niche in video surveillance that makes it an invaluable tool for protecting yourself and your property. To ensure the absolute best protection available, EZ Watch Pro version 4.0 offers support for both IP cameras AND analog cameras. For customers using an Analog Camera system, they would install one of the EZ Watch Pro 4.0 video capture cards and connect their cameras directly to the PC. If you choose to use IP cameras, we ship out a specially customized version of the software which does not need a capture card, merely a license (Provided in the form of a small USB 'key') to use the software with a certain number of cameras. For customers using both, both the capture card and the USB license key is provided to allow both direct connections and the network connections to be used. IP cameras and Analog Cameras can be used together on the same screen, side-by-side. You can even add IP cameras from a remote site to be recorded from an EZ Watch Pro DVR, without requiring a DVR at the camera's location!
For additional information on our analog camera kits and DVR solutions, please see our PC Based Security Systems.
For additional information about EZ Watch Pro's IP camera support, please see our IP Network Video Recorders.
As always, if you have any questions about the capabilities of Analog or IP cameras that is not answered here, or if you'd like expert advice on which cameras to use for your installation, please feel free to Contact Us. Our support and sales representatives will be happy to help you however we can.
