IP Camera, also known as Network camera sends and receives data over internet and thus facilitates monitoring of a specific area from any part of the world. Since, most of the IP cameras are meant for security purpose, they are also called network security cameras.
Unlike their Analog cousins, Network cameras transmit digital video over a network connection. So, an Internet Protocol camera will transmit data over a network to a central storage server or can either save a video to an on-board SD card storage.
How does a Network Camera collect and compress images
IP Cameras capture images with a similar concept seen in digital cameras. The only difference is that network cameras compress the files and transmit them over a network, whereas digital cameras lack this capability.
In environments where network infrastructure is already in place, an IP camera installation becomes simple. If in case the need for only two- three IP cameras arises, then decentralized cameras are the best option. A decentralized camera captures images and has the ability to store on its on-board storage. While a network camera captures the image and sends it to a Network Video Recorder (NVR) to allow remote viewing. For applications needing many number of IP cameras, an NVR becomes necessary.
An NVR is a software defined appliance used for viewing multiple cameras at a time and storing their respective video content on it. The main difference in between a Digital Video Recorder (DVR) used in analog surveillance and an NVR used in IP Surveillance is that a DVR encodes and processes videos obtained from analog cameras. Since, IP cameras encode the videos on their own, NVR facilitates centralized remote viewing and storage. NVR software can be installed on a device having its own operating system like a personal PC.
As the demand for new technology is on the rise in surveillance field, the demand for Hybrid systems is also increasing. A hybrid DVR can accept both IP and Analog inputs and so it can be used in environments where IP and Analog cameras are deployed.
How can a network camera be connected?
An IP camera can be connected through wired and wireless network.
Wired- Wired networks are those which are laid out on Ethernet cables or fiber optics. The camera needs to be connected to a router or a modem and it will start its work functions from then on. As a wire line network avoids signal interception and interference, a wired network camera layout is preferred for most of the applications.
Wireless- Wireless networks can be established by using WiFi routers or cellular network SIM cards. But at the same time wireless networks connectivity in surveillance is prone to signal interception and interference hence the transmission of data may be affected.
Image resolution vs. Compression technique
Image resolution is measured in pixels in digital world. So, a detailed image becomes directly proportional to the number of pixels. The more pixels are included in an image, the more detailed image with clarity can be obtained. But the fact is that these detailed images need more bandwidth for transmission and more space on a hard disk.
So, in order to transmit the images over a network by using less bandwidth, data compression techniques are useful. A number of data compression standards exist in the industry and out of those, H.264/MPEG4 are most used.
Network camera usage benefits
IP cameras can act as a good replacement to traditional analog security cameras, as they offer a bouquet of benefits. Apart from remote viewing, IP cameras can be laid on existing internet connections. As internet acts as a transmission medium, anyone can utilize the services without the need of additional monitoring equipment. There is no limit for the IP camera deployment in a surveillance environment, provided bandwidth is also proportionately available.
Need for Static IP Address
Network cameras need Static IP address and only an Internet service provider can provide it on demand. Generally, when a device is connected to a network, one can access it by entering its IP address. But dynamic IP addresses change every time when you reconnect to a network. For this reason, Static IP address is delivered to those devices which need to be consistently connected to a network. Sometimes virtual static IP address providers can also offer the service.