Watch this way: CCSO has advice for 20/20 vision
- Patrick Sherman
- Clackamas Review - News
Police say surveilance cameras are no use if they aren't placed and used properly
Big Brother is watching, but he is sitting in the cheap seats - that according to investigators and detectives with the Clackamas County Sheriff's Office, who rely on video surveillance systems to prosecute robberies and other crimes.
'Small merchants employ these systems to protect themselves. A lot of that is for insurance purposes - people slipping and falling in the aisles - or employee theft, but we have arrived at a new level of technological development that we're not using to our full advantage,' said Detective Jim Strovink, public information officer for CCSO. 'We need to focus these cameras on the faces of these individuals. Eye-level placement will provide the best opportunity to capture usable images of a subject.'
That advice resonates with Joyce Nagy, the office's certified video forensic analyst.
'If you have your cameras placed correctly, you can do a lot with the system you already have,' she said. 'I've seen a ton of videos, and a lot of the time the camera placement is really inefficient.'
Ceiling-mounted cameras can easily be foiled by a perpetrator wearing a baseball cap, and often are too far away from the subject to provide conclusive identification, even if they do capture a crime unfolding.
'Good lighting is important,' said Nagy. 'Put the camera down low, next to something that the customer is going to look at - like the PIN pad attached to your cash register, or a colorful advertisement.'
For retailers who deal in high-value merchandise, a manned video surveillance system can be useful. It allows the operator to zoom in on suspicious activity, recording details that would be missed by fixed cameras.
'Sportsman's Warehouse on 82nd Avenue has an excellent system,' Nagy said. 'They have someone who monitors it - it's very clear, it's color, and their zoom is just incredible.'
Even if cameras are placed in useful locations, the images that they record must be sharp. VHS tapes wear out after being re-recorded five times, leading to distorted images and lost information.
'Sometimes, people will use the same tape over and over and over again,' said Nagy. 'There have been times I've had to literally blow the dust off a tape - those get eaten by my machine because the tape is so dirty.
'We worked with a bank which put numbers one through five on their VHS tapes, and every time they recorded on a tape, they crossed off a number. That worked terrific.'
Another hazard to the images stored on video tape is over-use during the investigation itself.
'Sometimes, we kill our own evidence, by having a detective watch the same event over and over again, which wears out that part of the tape and degrades the images,' she said. 'The shopkeeper can do the same thing. I just had one of those recently - he watched it and watched it, which made it difficult to enhance.
'The pause button is another no-no. The tape stops moving, but inside the VCR, that cylindrical video head is still spinning, which wears out the tape.'
Digital video systems overcome many of the drawbacks inherent in tape-based recordings, but they can present their own unique problems.
'They record video straight to a hard drive, which can be burned on a CD or a DVD, but each system uses its own codec,' said Nagy. 'If I don't have the right codec for a particular recording, I have to go onto the Internet and find it, or sometimes the shopkeeper will put the codec on the CD for me to use - but there are still problems at the DA's office and at other agencies who also need to view it.'
Digital recordings also provide fewer opportunities to enhance the image, such as combining several frames to create a clear image of a subject that is otherwise obscured.
In her work, Nagy uses a $22,000 piece of software to enhance and edit video, but its capabilities still fall far short of what viewers see on television crime dramas.
'The stuff you see on TV that's really cool either doesn't exist, or we can't afford it,' she said. 'I don't change anything about the existing image - it's more like turning on a light in a dark room. I'm not changing anything about it - I'm just making it easier to see.'
According to Strovink, video surveillance systems are proliferating.
'In this country, each of us is captured on video about 12 times a day as we go about our business,' he said. 'In the UK, it's much higher than that, and you see the advantages of that when something like last year's subway bombing happens.
'Is Big Brother watching? You don't have to be blunt about it, but if you have a camera on the countertop, where you can get a good, clear, crisp image of that person which we can circulate, we're miles ahead - the criminals are going to be identified that much quicker.'