VK4ZXI

Digital Video Processing with HD CCTV: Noise reduction In this post I examine some of the sophisticated technology used in digital high definition CCTV cameras, including a the powerful underlying SOC electronics, and the similarities with audio noise reduction in audio, as used in amateur radio. Noise reduction in HD CCTV I read very widely and like to see or create connections between apparently disparate ideas and technologies. From an earlier post on working with a Pentax lens I have, I read about the image processing abilities of some Pentax lenses.   Pentax/Richo have an award-winning image processing system, PENTAX Atmospheric Interference Reduction (PAIR). http://www.ricoh.com/fa_security/security/pair/  The results are amazing:       From a first reading, the processing seems to be done in the lens itself, something that had me mystified as to how such spectacular results are possible with just optics. However, on closer reading, th...

Achieving 4K UHD DATV- very draft Perhaps a little early, but 4K DATV may be more achievable than I first thought. It would be a bit of a technological coup if amateur radio can do 4K before regular free-to-air broadcast TV. 4K video cameras and monitors are already relatively inexpensive. 4K TV capture/switchers are available and not too expensive. The missing link are modulators, transmitters and receivers, but may be possible using inexpensive SDR TRX; they can already do DVB-T/S. As far as I am aware, broadcast TV is still struggling with Full HD digital TV in some countries, notably the USA with a very large number of small TV stations and the not insignificant cost of having to replace virtually everything, other than their antenna. I suspect the same across some of Europe and Asia. For both terrestrial and satellite, while they may have digital TV, most of it is SD (standard definition) or HD (high definition 720p), rather than wide-screen Full HD (1080i; wish it was 1080p...

My journey in DATV and the future: 4K UHD or internet-linked DATV repeaters; Not that crazy? Draft In this post I want to briefly outline my DATV journey and a quest for Full HD DVB-T. I have achieved this in a relatively short time and out of some of my difficulties, have wondered if first, 4K UHD DATV and, second, network-linked DATV repeaters, are possibly not that distant. In this post I will outline my journey, as the future is path dependent, history matters! In the following two posts I will consider ways to achieve 4K UHD and internet-linked DATV repeaters. My DATV journey: Live Full HD DVB-T Personally, coming late to DATV at the beginning of 2013, with a 40 year break in my amateur radio activities (see my first post), I have not had to put in the extreme effort and expense of either analogue TV or digital TV, particularly over the last decade, such as by the DATV Express team, among many others. Before returning to amateur radio I had spent considerable time and...

  Converting CCTV lens from video auto iris to DC auto iris Summary It seems relatively easy to convert a video auto iris CCTV lens to DC auto iris and for a modern camera to control the lens correctly. I was able to convert a sophisticated expensive CCTV lens to DC auto iris, which otherwise was unusable.    However, I give no guarantee that it will work with any other lens, although I think the principle is the same.   If camera control is not possible or desired, it is possible to at least open the lens's iris with a voltage through a series resistor applied to the drive motor with the correct polarity. The problem I had bought a Pentax motorised zoom and focus lens for use in my amateur TV studio with the idea of using it on a remote-controlled tripod as part of a one person operation. Motorised lens are not cheap ($600), but I bought a new, but old stock, lens cheap (<$100).   The main problem was that the lens used video...

DATV DVB-T BlackMagic Design ATEM TV Studio: Proof of concept An objective has been to get high quality video and audio, as well as TV production studio abilities for my DATV DVB-T system. Production studio abilities includes the capacity to switch between multiple live TV cameras, recorded media and overlays, such as my call sign. I originally experimented with software production systems, mainly aimed at network feeds, such as Vidcaster and Open Broadcaster. The commercial Vidcaster software has a virtual camera that can be the input video stream for a HiDes's device, such as the UT-100C via PC2TV. This required a fast PC, a HDMI video capture card from a DSLR camera, the Vidblaster software, the PC2TV software and the UT100C all working properly; a difficult feat many of us have stumbled on. An alternative is to use a hardware production studio. The BlackMagic Design ATEM TV Studio is very suitable and a reasonable price, about $1000, given its capabilities. It is desig...