videobruce 0 Posted March 27, 2007 This very well written article came from CCTV-Focus magazine (Australia). Though much of it doesn't surprise me as I have seen alot of this in the video production product business. It really is a notice to the CCTV industry on just how poor a job they are doing (edit the 'dot'); cctv-focus DOT com/cctvfocus37_unravel.pdf (I will warn in advance, this is a tool to sell a Elbex CCTV tester, but it isn't anywhere near as bad as I have seen from other manufactures that publish articles specifically to sell their product. Sencore being the worst.) They also have a very nice full screen test pattern on their site; cctv-focus DOT com/tpg-8_cctvlabs_pattern_3_1.jpg Share this post Link to post Share on other sites
phred 0 Posted March 27, 2007 The guy may have a point but has something to sell and proceeds to overstate the case. Amongst the techno-babble there are a number of errors Example- '.For mpeg2 or mpeg4....noise...reducing substantially the frame refresh rate'. Exactly the converse of the truth. He appears not to know about variable bit rate encoding or dynamic noise reduction. I find this strange as in other articles he claims to know Lee Tracey, past technical director of Wavelet Technology. Share this post Link to post Share on other sites
videobruce 0 Posted March 28, 2007 I understand he has something to sell (hence the warning in the 1st post), but being familar with 'sales' hype in both the consumer and 'professional' world, you have to admit what he says about the quality of CCTV images is dead on. The best CCTV image I have ever seen looks like crap compared to the worst local originating cable TV broadcast (public access) which are usually pretty bad to begin with. His "techno-babble" has far more truth then anything else I have read regarding CCTV equipment. There are too many 'sell and run' artists who will con the customer into almost anything no matter how poor the image is as long as the $$ is there. Tell us, what are the other areas where you think he is in error? Share this post Link to post Share on other sites
phred 0 Posted March 28, 2007 I do not disagree with the general point that resolution and image quality of cctv leaves room for improvement or that there is a great deal of hype around. However, a great deal of time, effort and money is being poured in to improve the situation. We now have mult- megapixel IP cameras that will do a better job than your TV company in terms of resolution – you can have it if you are prepared to pay. The images from cctv included in the article appear to be from old VCR recordings and are very poor compared with what I see now from good quality cameras and recorders. People still determined to do cctv on the cheap will get 'cheap' results. The final disappointment for me is that the article does not provide a solution, like a better camera or recorder, all it sells is a means of confirming the problem. I have no desire to nitpick through the whole article but here is just one other glaring fudge - - the use of ½ inch cameras may reduce the cost of the DVR's HDD by many times the extra cost for the cameras. Share this post Link to post Share on other sites
videobruce 0 Posted March 28, 2007 I remember reading that. It sounded kinda odd to me. I'll give you that one. As far as coming up with a solution, at least he brings to the table the problems many are unaware of. Maybe you could bring to the table some solutions (other that IP cameras). Share this post Link to post Share on other sites
phred 0 Posted March 28, 2007 I am working on it but it will have to be IP. Without IP you are stuck at the maximum resolution of D1 so you must work within that limitation. You simply cannot cover a large area at that resolution and expect to get face recognition at a distance, no matter how good the hardware is. Share this post Link to post Share on other sites
videobruce 0 Posted March 29, 2007 Is this the 'D' categories/specs you mentioned?; hdtvmagazine DOT com/forum/viewtopic.php?t=6350 Share this post Link to post Share on other sites
phred 0 Posted March 29, 2007 Same idea but measured in pixels. D1 = 720X576 pixels for PAL and 720X486 for NTSC (same as dvd video format) You will also come across the term CIF CIF = 352X288 for PAL and 352X240 for NTSC Share this post Link to post Share on other sites
videobruce 0 Posted March 29, 2007 When you refered to "D1", my understanding there are 4 or 5 "D" specs for CCTV digital recording, or am I getting thsi wrong? Share this post Link to post Share on other sites
phred 0 Posted March 29, 2007 D1 is the maximum recording resolution for most cctv DVRs. A few companies have worked on HDTV for cctv but I don't see a future in it since IP has so many advantages. Share this post Link to post Share on other sites
videobruce 0 Posted March 29, 2007 That (edited) link I posted, is that the same 'D1' as you mentioned?? Share this post Link to post Share on other sites
phred 0 Posted March 29, 2007 Yes, D1 and CIF are terms borrowed from TV standards. In cctv they only refer to the horizontal and vertical pixel count – they do not define frame rate or colour encoding. Share this post Link to post Share on other sites
videobruce 0 Posted March 29, 2007 Aren't there terms defining recording for CCTV applications? Share this post Link to post Share on other sites
phred 0 Posted March 29, 2007 It is digital at the recording end so terms are the same as those used for digital video. -resolution in pixels, frame rate per second, file size per frame, compression standard used. There is no set standard like for TV In practice the maximum for a DVR is usually 720x576 at 25 fps per channel with a variety of compression types. Share this post Link to post Share on other sites
videobruce 0 Posted March 29, 2007 Conversation with a vendor about DVRs' brough up the terms D1 thru D4 or D5 (don't remember). It was stated it was a quality rating (not exact words) regarding the recorder. Share this post Link to post Share on other sites
CollinR 0 Posted March 29, 2007 Yeah, I wouldn't be buying from them... Share this post Link to post Share on other sites
videobruce 0 Posted March 29, 2007 Sounds as he was just misinformed. Share this post Link to post Share on other sites
phred 0 Posted March 30, 2007 You're being very generous. The maximum recording resolution and frame rate are fundamental DVR specs. This is really basic stuff, anyone who does not know what these figures mean should not be selling DVRs, they are in no position to give good advice. Share this post Link to post Share on other sites
videobruce 0 Posted March 30, 2007 Benefit of the doubt? He wasn't 'scamng' me. I was in sales long enough to know better. Share this post Link to post Share on other sites