Up to 16 security cameras can be supported using a single video decoder chip, following the announcement of a new family of high performance devices by TDC. The development eliminates the need for a separate multiplexer chip in a great many applications, simplifying the design of advanced, multi-channel video surveillance and recording systems.
Designated the Conexant CX25853 the new device from TDC offers eight integrated analogue video decoders each with two composite inputs allowing the user to multiplex between a total of 16 cameras. TDC is also offering the CX25850 and the CX25851 with four decoders supporting up to eight composite inputs. All three devices embed two video encoders which allow the display of either any two of these internal video channels or an external video feed from another video decoder. A monitor output, able to switch between decoder paths or multiplex multiple decoder paths together, is also provided.
The Conexant devices are suitable for use in both real-time and non-real-time applications. In real-time systems, the product family can support four or eight video channels at a full frame rate of 30 frames per second (FPS). For non-real-time systems, the CX25850/1/3 can fast lock within one field, minimising frame loss and maximising switching frame rates. The family of decoders is optimised to handle low input signals, which is typical in video sources at long distances from the DVR.
Conexant CX25850/1/3 decoders have been specifically designed to deliver quality video, using multiple 10 bit ADCs, each with an independent 4H adaptive luminance and chrominance comb filter for NTSC and PAL. All three decoders feature a full ten-bit data path right through the device. Additionally, each video decoder has an independent scaler which can reduce the video image size down to one-eighth its size both horizontally and vertically.