Having the analogue world IP-connected
IP-based video is taking an increasing role in modern security video systems. However, the transition away from analogue systems may take time for various reasons, such as investment costs, IP security and maintenance-related topics. If the system to be built is anything other than a purely new Green Field Deployment, there are alternative ways to connect a legacy analogue system to an IP network.
Broad selection of IP encoders and decoders for various applications
The most simple form to connect an analogue camera to an IP-based video surveillance system is to use an IP video encoder. The encoder converts the analogue composite video to IP-based video in the desired format (specific video protocol, resolution and frame rate, etc.). Furthermore, for PTZ cameras, the required controlling data can be fed through the same encoder by using built-in telemetry terminal server functionality. Many encoders also have additional features to support audio and digital I/O communication. The connection to an Ethernet network can be done locally (up to a distance of 100 metres) by using CAT cable. In case a distant analogue camera was remotely operated over an optical transmission system, an IP encoder with an optical network interface can replace the link and utilize the same fibre optic cable. Finally, the encoder joins the Ethernet network typically over an Ethernet edge switch.
The video streams can be distributed in the Ethernet network either by unicast or multicast protocols. Multicast enables the reception and decoding of video among multiple concurrent system users without consuming network bandwidth. The decoding can be done either by hardware IP decoders or software-based VMS clients.
Hardware for harsh environments
The outdoor cameras are specified and engineered into housings that withstand harsh conditions. This applies to specific Teleste encoders as well. When installed in the proper housing, they can meet operational temperatures such as -34 to +74 °C, depending on the model. The typical EMC requirements are also met. Some Teleste video hardware is specified to meet rail track-side requirements such as EN50121 or roadside deployments as specified in the Nema TS-2 US standard.
Multistandard video protocols
Teleste encoding and decoding solutions support various video formats, depending on the model. The latest generation devices support the H.264 High, Main and Basic profiles. Models supporting MPEG-4 (SP & ASP), MPEG-2 (MP) and MJPEG are also available. Some hardware products support several formats by default, and additional formats can be activated by specific license keys.
Typically, most of the encoders and decoders are connected to cameras and monitors over composite video interfaces (BNC). Some advanced Teleste devices also have video connectivity over HDMI or HD-SDI interfaces.
