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bike theft news
http://ktla.com/2017/06/19/video-cap...bicycle-store/
-- Andrew Muzi www.yellowjersey.org/ Open every day since 1 April, 1971 |
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#2
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bike theft news
On Tuesday, June 20, 2017 at 6:22:21 AM UTC-7, AMuzi wrote:
http://ktla.com/2017/06/19/video-cap...bicycle-store/ One would think that the police would have some clues. |
#3
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bike theft news
On 6/20/2017 9:22 AM, AMuzi wrote:
http://ktla.com/2017/06/19/video-cap...bicycle-store/ Motion-activated lights indoors would make that surveillance camera a lot more useful! Also, about the fake customer ride-away mentioned in the video: ISTR having to leave my driver's license when test riding a bike. (It may have depended on whether I was with my wife, whether I arrived on foot or by car, etc.) Andrew, what's your policy on that? Anyway, hope the perp gets caught. Around here, he'd probably be an addict desperate for cash. -- - Frank Krygowski |
#4
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bike theft news
A couple of weeks ago I went by a bike shop
that I had previously stopped by its window to admire a bike at some 80 000 SEK, which is ~($9104, £7208, or €8184). There was a rent-a-cop car there and I didn't take notice until I saw someone had thrown a paving stone (?) thru one of the windows. First I thought it was some kids doing their routine but then it hit me it was the same window that used to sport the bike! There was no fence so just smash and grab. Here is a Swedish forum thread [1] with a photo. What kind of bike is it? It says they busted the guy! They also say, pathetically, "the bike is worthless to the thief as he doesn't have the charger to the battery". [1] https://happyride.se/forum/read.php/1/3162334/3166769 -- underground experts united http://user.it.uu.se/~embe8573 |
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bike theft news
On 2017-06-20 06:22, AMuzi wrote:
http://ktla.com/2017/06/19/video-cap...bicycle-store/ Why is it that most surveillance capture is of such poor quality as in the videos shown here? Do we need to dunk the designers of those "systems" into a moat? That has helped in medieval times when bakers were selling substandard rolls. It is ridiculous to ask anyone "Call if you recognize this guy" when all you can see is a fuzzy blob. Even the rather web cams I use for online conferencing are WAY better than that inadequate "surveillance system" that this store has. None of mine has cost more than $20. That store owner should have all that video stuff ripped it out and get something decent. Now. They should have made that decision two weeks ago when the previous theft happened and the perp is totally unrecognizable. Most thieves have a long rap sheet but finding them in the police database requires pristine video capture. In this day and age that is a piece of cake. It even was in the mid 80's. I designed a CCD camera back then which took crystal-clear computer-controlled shots so I really do not understand why shop owners put up with such junk. This is where the state-of-the-art stands, where you can zoom into every facial or clothing detail: https://www.security-camera-warehous...urity-cameras/ -- Regards, Joerg http://www.analogconsultants.com/ |
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bike theft news
On Tue, 20 Jun 2017 11:27:27 -0400, Frank Krygowski
wrote: Motion-activated lights indoors would make that surveillance camera a lot more useful! Not really. The problem with aiming a motion activated surveillance camera through a window is that everyone that passes by sets off the motion detector. The better DVR (digital video recorders) have programmable zones. The viewing area is chopped into small rectangular zones, each of which can be set to detect motion or ignore motion. This helps, but is far from perfect. Something like this: http://surveillance.aver.com/Images/Shared/IMD%20revised.jpg where only the door areas detect motion. The big problem with camera placement is the field of view usually ends up many times wider than a person's head. My guess(tm) is the camera field of view at the window was probably 20 times the width of a person's head. If the camera was a better quality 1920x1080, the persons head would be only: 1920 / 20 = 96 pixels wide. Try to identify someone from a photo where the person's face is only 96 pixels across. Here's me at 660 pixels across: http://802.11junk.com/jeffl/pics/jeffl/slides/jeffl-07.html and at 96 pixels across, expanded to the same image size: http://802.11junk.com/jeffl/pics/jeffl/jeffl-07-96.jpg 96 pixels across actually looks fairly good, but only under ideal conditions. Add to that the distortion caused by positioning the camera at about 45 degrees downtilt near the ceiling, marginal night time lighting, and a possible disguise. Also, the same camera would easily produce a recognizable face photo if the field of view was reduced to perhaps 5 times the width of a person's head, but then the field of view at the front window would be too small to be useful and require multiple cameras to cover the entire window. Incidentally, my favorite mistake is to put cameras on the ceiling, which usually produce great a video of the top of the burglars head, hat, or hoodie. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
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bike theft news
On 6/20/2017 10:49 PM, Jeff Liebermann wrote:
On Tue, 20 Jun 2017 11:27:27 -0400, Frank Krygowski wrote: Motion-activated lights indoors would make that surveillance camera a lot more useful! Not really. The problem with aiming a motion activated surveillance camera through a window is that everyone that passes by sets off the motion detector. What I had in mind was a motion detector controlling a light, not (necessarily) controlling the camera. The idea is to illuminate the face of someone coming into the shop. Recording that illuminated image is a separate issue. -- - Frank Krygowski |
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bike theft news
Jeff Liebermann wrote:
On Tue, 20 Jun 2017 11:27:27 -0400, Frank Krygowski wrote: Motion-activated lights indoors would make that surveillance camera a lot more useful! Not really. The problem with aiming a motion activated surveillance camera through a window is that everyone that passes by sets off the motion detector. The better DVR (digital video recorders) have programmable zones. The viewing area is chopped into small rectangular zones, each of which can be set to detect motion or ignore motion. This helps, but is far from perfect. Something like this: http://surveillance.aver.com/Images/Shared/IMD%20revised.jpg where only the door areas detect motion. The big problem with camera placement is the field of view usually ends up many times wider than a person's head. My guess(tm) is the camera field of view at the window was probably 20 times the width of a person's head. If the camera was a better quality 1920x1080, the persons head would be only: 1920 / 20 = 96 pixels wide. Try to identify someone from a photo where the person's face is only 96 pixels across. Here's me at 660 pixels across: http://802.11junk.com/jeffl/pics/jeffl/slides/jeffl-07.html and at 96 pixels across, expanded to the same image size: http://802.11junk.com/jeffl/pics/jeffl/jeffl-07-96.jpg 96 pixels across actually looks fairly good, but only under ideal conditions. Add to that the distortion caused by positioning the camera at about 45 degrees downtilt near the ceiling, marginal night time lighting, and a possible disguise. Also, the same camera would easily produce a recognizable face photo if the field of view was reduced to perhaps 5 times the width of a person's head, but then the field of view at the front window would be too small to be useful and require multiple cameras to cover the entire window. Incidentally, my favorite mistake is to put cameras on the ceiling, which usually produce great a video of the top of the burglars head, hat, or hoodie. You can have glass break sensors turn the lights on. -- duane |
#9
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bike theft news
Turn cam 180
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#10
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bike theft news
On Wed, 21 Jun 2017 00:11:12 -0400, Frank Krygowski
wrote: On 6/20/2017 10:49 PM, Jeff Liebermann wrote: On Tue, 20 Jun 2017 11:27:27 -0400, Frank Krygowski wrote: Motion-activated lights indoors would make that surveillance camera a lot more useful! Not really. The problem with aiming a motion activated surveillance camera through a window is that everyone that passes by sets off the motion detector. What I had in mind was a motion detector controlling a light, not (necessarily) controlling the camera. Ummm... if the shop is dark, how is the camera going to see the burglar so that the motion detector will work? Either the camera runs on infrared, which produces some rather low resolution b&w pictures, or it runs on something else, like window breakage detector, RF doppler detector, or perhaps a trip wire. Most cameras and DVR's have a nifty feature. In low light, the cameras switch from color to b&w, where they are more sensitive. The motion detector actually works better in b&w. If motion is detected, it turns on the light and everything is now in color. Just one problem. It takes about 5 seconds to switch from b&w to color. Longer to go the other direction, but that's not important here. What happens is during that 5 seconds, the DVR sees a washed out image caused by too much light and a sensitive b&w camera mode. When the color finally comes on, it takes a while for the auto-aperture and auto-focus to kick in. My guess(tm) is loose another 2 seconds. Seven seconds is a long time for catching a smash and grab burglar. The idea is to illuminate the face of someone coming into the shop. Recording that illuminated image is a separate issue. I setup one store with a cheap conventional digital camera and a strobe. The camera was in machine gun mode taking about 1 frame per second. The strobe did a much better job of catching a photo of the burglar, but also was great for temporarily blinding the burglar. In two out of 4 attempted smash and grab burglaries, the thief was so startled that he ran away empty handed. This would have been an ideal scheme, except there's a problem. False triggering of the motion detector just wastes some bytes on an SD card or hard disk in the DVR. No problem there. However, if the flash goes off during business hours, or zaps a passerby through the storefront window, it's a problem. The big worry is that some passerby will do a slip and fall act, claiming that they were flash blinded by the camera system. Full disclosu I don't normally do security camera systems. One of my friends works for a security company that offers camera installation and monitoring. He was clueless about cameras, so he asked my help, resulting in the clueless helping the clueless. We proceeded to repeat all the basic mistakes, until we found someone with many years of experience, who offered to educate us in trade for me fixing his computer nightmare and a few goodies. We both learned quite a bit and discovered that many of the cheap DVR's don't work very well. For example, one such device can feed video back to a computer via the internet. Nice feature, but if while you're watching the store, the recorded video turns to low resolution crap due to insufficient CPU horsepower. All of the smartphone apps I tried have bugs or are useless. One took so long to boot up, that if there were a power glitch, the burglary would be over before the DVR started recording. I got to play with some rather high priced DVR's and soon discovered the difference between cheap junk from eBay and overpriced quality equipment. I put an end to my security camera sideline about 2 years ago, when I ran into medical issues that made running cables a bit of a risk. 4:40AM and I can't sleep. My time share cat and the resident mouse have made some kind of non-aggression pact. The mouse gnaws on something in the wall, while the cat does nothing. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
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