Guest fathead Posted May 4, 2005 Posted May 4, 2005 Wow, did not expect much response - too much for me to cope with all at once. _____________________________________________________________________ Quote for identification the subject has to cover 120% of the recorded image size, not 120% of 10% of the original recorded image. --------------------------------------------------------------------------------- This is a real problem . Will have to look into this. wonder if this rule was put in place because of the resolution issue. Ptz, high res, intelligent zooming, IP cam. Great stuff, probably the ultimate solution and I realise that what I am suggesting can be done by other means but only for a very high price. The digital camera I am using cost about £250 and a lot of that cost is the fancy case, lcd screen and various other parts that would not be required. Samsung just put a 6 megapixel camera in one of their mobile phones. Can
Guest fathead Posted May 4, 2005 Posted May 4, 2005 When a PTZ is displaying a 'zoomed out' image it may be 480TVL resolution, however when it's 'zoomed in' to a specific area, the resolution is still the same. If you take a 3Mpixel digital camera and take an image of a wide area, it will contain 3 million pixels, so if you concentrated on an area 10% of the image size, the viewed image would only be 300, 000 pixels. In other words, you would lose quality/resolution every time you 'zoomed in' compared with optical zoom. ------------------------------------------------------ Digitals have optical zoom too - I can control mine from PC.
Brian c Posted May 4, 2005 Posted May 4, 2005 Digitals have optical zoom too - I can control mine from PC. 51273[/snapback] Very true, but in your scenario the image will already have been captured and you'd be digitally, zooming in on playback. With the PTZ tracking, the optical zoom will be in use during recording, with no need for digital or optical zoom on playback. (In theory!) If you don't know......ask.
Rich Posted May 4, 2005 Posted May 4, 2005 Wow, did not expect much response - too much for me to cope with all at once. ____________________________________________________________________ Quote for identification the subject has to cover 120% of the recorded image size, not 120% of 10% of the original recorded image. --------------------------------------------------------------------------------- This is a real problem . Will have to look into this. Its a human rights issue, I suppose initially it may have had something to do with resolution issues, but even with the highest resolution of cameras I doubt the rule will change, its about the quantity of information in an image rather than the quality. going back to your first question about taking one large image and then displaying it at full resolution on a hi res tv, I think you may find that it would be acceptable, if the image was 120% of the visible screen and the subject matter was clear. You would however need to ensure that the information could be easily played on a free self executing programme which means it would need to be standard, the only thing that comes to mind is vector images. CCTV Cameras use a CCD device, there are many types and these determine usually the quality of the camera. There are many other considerations for a CCTV cameras though, like lens control, shutter speeds, back light compensation etc. There are digital CCTV cameras available, as there are digital IP cameras with servlets built in to enable the camera to have an ip and for it to serve live images using a desired codec to a suitable recording device. Take into account that a dedicated cctv network will cater for all the bandwidth it requires, but then try to do the same with an existing network and you will get problems, also for remote viewing of cctv, you are limited by 250kb upload speeds by most internet providers. I love playing with ideas also, last week I had an idea of a 35mm digital film, basically a standard cartridge that contained capture, storage and power and control for a ccd chip that would take the place of a standard negative frame. I then check on the net and found that the idea had been thought of 6 years ago and that a similar idea has already been achieved, using ccir I believe.
Guest fathead Posted May 4, 2005 Posted May 4, 2005 Its a human rights issue, I suppose initially it may have had something to do with resolution issues, but even with the highest resolution of cameras I doubt the rule will change, its about the quantity of information in an image rather than the quality. going back to your first question about taking one large image and then displaying it at full resolution on a hi res tv, I think you may find that it would be acceptable, if the image was 120% of the visible screen and the subject matter was clear. You would however need to ensure that the information could be easily played on a free self executing programme which means it would need to be standard, the only thing that comes to mind is vector images. ------------------------------------------------------------------------------ displaying a jpeg still image is pretty standard though. you could always do a humungous print Silicon Film was a great idea - would still like to see something like that as I have a very expensive Nikon gathering dust. Once you have tried digital it is hard to go back. It just depends on demand and can it be done at the right price. Expect my idea could be done very cheaply but without demand from the folks here who install the stuff it will just remain an idea.
Guest fathead Posted May 4, 2005 Posted May 4, 2005 also for remote viewing of cctv, you are limited by 250kb upload speeds by most internet providers. ------------------------------------------------------------- you would still have all that from the video cams - remember I am not talking about replacing eveything with digital stills - just think of it as a worthwhile inexpensive enhancement - another tool in the armory.
Guest fathead Posted May 4, 2005 Posted May 4, 2005 Very true, but in your scenario the image will already have been captured and you'd be digitally, zooming in on playback. With the PTZ tracking, the optical zoom will be in use during recording, with no need for digital or optical zoom on playback.(In theory!) 51275[/snapback] ----------------------------------------------------------------------------------- OK .. what happens when the sofware controlled PTZ is zoomed in on a couple of pidgeons or the inocent guy ..meanwhile the villain is out of shot and you get nothing. I am very impressed with the technology of these cams but they are way to expensive for a more modest setup and they can be fooled.
secboy Posted May 4, 2005 Posted May 4, 2005 [Just thought ! you said earlier that your cameras would be collecting images at 1 x frame per sec thats not very good a guy on the run might just get his heal in the frame???????????? or have i got the wrong end of the stick fatboy.Paul
Guest fathead Posted May 4, 2005 Posted May 4, 2005 Very true, but in your scenario the image will already have been captured and you'd be digitally, zooming in on playback. With the PTZ tracking, the optical zoom will be in use during recording, with no need for digital or optical zoom on playback.(In theory!) 51275[/snapback] ------------------------------------------------------- oops! do not think I explained that too well . when I say I can control the zoom from the PC I mean I can control the zoom lens fitted on the camera just as you can with the cam you are refering to.
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