AHD DVR & Cam
AHD DVR & Cam Security Camera Installation
AHD CCTV is an analog high definition closed-circuit television video surveillance standard that uses coax cable to transmit HD video from security cameras to DVRs. AHD supports 720p and 1080p HD video resolutions. AHD’s birth, is to solve the transmission distance limitations of existing HD-SDI solution. As one of new HD analog solution, AHD supports video transmission over traditional 75-3 coaxial cable up to 500 meters, and it becomes another alternative for HD analog solution. By the way, it inherits and carries forward advantages of traditional analog solution, video signal are uncompressed, keep all the original video details, to truly achieve high definition uncompressed loss less, no video latency effect.
Similar to other HD analog solutions, through using the progressive scan CMOS image sensor, the AHD camera can deliver 1.0 megapixel, 1.3 megapixel, 2 megapixel resolution, added with ICR filter, the camera achieve true day/night video surveillance; and same like the traditional analog system, AHD products support plug-and-play installation, easy to use.
AHD tech core features:
High image quality at the resolution of 720p/1080p
The technology uses a progressive scan while forming a signal and division of brightness and color components of an analog signal: that allows eliminating a blur and blinking, improving a color reproduction.
Reliable and inexpensive connection
AHD data transmission technology doesn’t lay a big claim on a coax cable quality. That’s why any available cable can be used for data transmission, including a composite one.
Long distance of a network laying without quality losses
Video data is transmitted without quality losses at the distance of 500 m.
Qualitative video without latencies
No signal latencies, indicative for IP-systems.
AHD video recorders can work in three modes, namely with three types of video cameras: standard analog D1/960H, AHD and IP ones. That allows to connect already installed IP or/and standard analog video cameras to AHD video recorder.
AHD video recorders can be easily integrated in an existing video surveillance system, in this case old analog video cameras can be replaced with AHD ones without any difficulties depending on a speed of a system modernization. AHD video recorders support a work with Cloud service and CMS systems, providing a remote control of a system; allow to manage PTZ devices, has alarm inputs/outputs, provide an ability of a backup and has several video outputs.
Modernization of an existing system without extra charge
An ease of installation, fettling and maintenance. A cost of AHD equipment is comparable to a standard analog video surveillance system equipment cost.
Compatibility with any trade marks
AHD technology is opened for all manufacturers, what allows a customer to choose AHD equipment of different rival manufacturers, not worrying about its compatibility.
The most important elements of AHD video surveillance system include:
- 1.3 or 2.0 megapixel CMOS-sensor is a part and parcel of a video camera, which transform a light flux, impinging on it’s sensitive part, into required electric signals, needed for a video image generation on a monitor or TV. It’s recommended to apply high qualitative CMOS0sensors, for example, SINY IMX 238, which have an increased sensitivity under a bad lightning (especially under IR range), for example, at night, in AHD video cameras. The most important sensor parameters are sensitivity, resolution, matrix size;
- SoC digital processor required both to receive an audio, video stream and other signals, save on a storage device and provide a convenient work of an operator of a video surveillance system under a high stability of all the system on a video recorder side;
- a video camera lens. An incorrect choice of a lens can make an image quality to become noticeably worth. So, details become blurred under a subnormal optical resolution.
A fundamental difference of AHD video cameras from standard CCTV ones is a work of ISP+AHD TX functional pair, which receives a signal from a high resolution matrix, makes a division of brightness and color components, enables to adjust a digital image processing (noise reduction. Backlight compensation, sensitivity, wide dynamic range etc.), processes PTZ-control, manage IR illumination, then transforms a digital signal into an analog one for transmission at long distances. IP video cameras differ from AHD ones by absence of a video compression, which also allows to avoid a video latency, appropriate to IP video cameras.
AHD RX audio-video codec performs the main function, which differs AHD tech from other ones, on AHD video recorder side. It can receive CVBS/COMET/AHD signals from a coax line, performing a digitalization and decoding, separation of color and brightness components, audio processing and other operations. AHD video recorder can receive audio-video and other streams from CCTV, HDCCTV, and IP video recorders in contrast to IP ones. In this case, a digital processor (SoC) processes an analog audio-video compression, but for a digital stream (from IP video cameras) SoC receives an already compressed one, as in regular IP video recorders.