Transcript
AHD 2.0 FULL-HD on analogue line The AHD 2.0 - AHD-H, or 2MP AHD - no longer a novelty, but not a common thing nowadays. The main reason that the recording just recently become solvable. AHD-H cameras are already available on the Hungarian market from the second half of 2015, but the recording solution (DVR) only began to appear in the last one or two months.
Short history of AHD CCTV The improvements started at the same time as the megapixels providing of IP CCTV cameras that had been envisaged development of existing analogue CCTV systems. It was the breakthrough in the last 2-3 years for the market waiting, which didn’t lower other developments and results of the virtues and standards. In this interval have emerged the technologies that have appropriate quality (HD720p) and offer an alternative to the 960H and D1 resolution providing CCTV solutions on close to analogue (or lower) price level. The AHD technology associated to the name of Korean Next Chip has began to spread in this period. The manufacturer presented the chips required for the manufacture of AHD-H solutions on the 2014 CPSE (Chinese Public Security Expo), but the market had to wait almost a year for production. The solution of Next Chip is based on a high sub-carrier frequency algorithm and "pseudo Y/C separation" technology. Physical peculiarities of the company's solution is the integration of AHD transmitter into the camera’s signal processing unit, and the AHD receiver into the DVR’s AV decoder.
Why good if it is bigger? So let's start at the beginning with the resolution! I would like to believe that we are experts (after all, we are in the security business) and can ignore the marketing messages made for a "simple" end-users. One such message, that the 720p and 1080p HD resolutions provide X times larger viewable area comparing to the VGA.
fake-felbontas.jpg (source: http://www.homesecurityhq.com.au) Generally, they like to mean greater than 2 for the "X" number. I would like to note here quietly, that the viewing area will not be greater many times than VGA just because of the particular camera imaging capabilities (720p or 1080p). The picture below is rather expresses the difference between the resolutions.
felbontas-2.jpg (source: http://www.unifore.net) The real and significant difference occurs first of all regarding to the (live and recorded) video material. The higher resolution: • guarantees better visualization (experience) at live and playback image; • the picture is much more detailed and have considerably more detail when you zoom comparing to (just for example) VGA video material.
For simplicity (and for AHD-H) in the case of FULL-HD monitor resolution we can admire the pictures below in case of different "camera-output 'resolutions: 960H resolution
tolvaj-960H-ex.jpg AHD-M (720p)
tolvaj-AHD-M-ex.jpg
AHD-H (1080p)
tolvaj-AHD-H-ex.jpg The zoomed inset seize (but does not cover 100%) the difference between the resolutions. For the 960H it can only be suspected that there are text on the board. For the AHD-M (720p) we know that this is text and the first letter of the first word is (presumably) "N". The AHD-H (1080p) already identify in a good chance that the first word is "NO". Who believes that this reason may be influenced by many ingredients, has the truth, but I refer scarce capability of this article.
Why good the AHD-H? I mean, beyond the above? Basically, the AHD-H is good, as the AHD-M also lived up to expectations: • excellent image quality - compression-free imaging and signal transmission; • there is no delay between the image displayed and the event; • no need to replace wiring of existing analogue system wiring, i.e.: a quick and cost effective installation / system "upgrade"; • favourable price level. The camera features are given. The key is: 1080p, with the advantages described above. Recorders (DVR) side has not too big surprise, that manufacturers – as my favourite, the IdentiVision - held all the advantages of the AHD-M (e.g.: image content analysis, receive conventional analogue cameras), which is now complemented by the 1080p AHD ability. Due to the new chip sets recorders are able to handle greater hard drives (up to 6TB). Just quietly and with each other: that's great, but it is cost-effective
if max. 4TB HDDs working in a recorder. Of course, it is also true that an 8-channel AHD-H DVR can record 240GB amount of data in one day (at 1080p resolution), so it will not hurt you, "if there are enough space". It is important to note that, contrary to previous rumour, the AHD-H recorders can handle cameras AHD-M images as well. So it is not needed to throw the full 720p system if we want to improve (but surely the recorder).
