Monday, October 24, 2011
A fight between two teenagers breaks out in a small pocket park in downtown Redlands, Calif. A dispatcher quickly turns a surveillance camera on the incident and surveys the scene while calling an officer to respond. Those around the scene do nothing to break up the fight, while one of the combatants receives a kick to the head. The perpetrator begins to leave the scene as a responding officer arrives. Arrest made, evidence on file, case closed.
Hales Park is located in historic downtown Redlands, providing a quaint gathering area for residents and shoppers. The challenge of providing a positive experience for residents and visitors requires a presence by the Redlands police. It’s not feasible to patrol this downtown core area 24/7. However, Redlands has established a virtual patrol through the use of surveillance cameras and audio.
Example: It’s not lawful to smoke in Hales Park. During a virtual patrol, a dispatcher notices an individual smoking in the park. Calmly the dispatcher reminds the citizen of the civic code via the audio system, avoiding the need to dispatch an officer to the scene.
The use of audio has significantly reduced calls for service for nuisance crimes, enabling an understaffed police department to do more with less. “The use of audio substantiates the monitoring of the cameras, and is a significant factor in intervention,” says Chief Jim Bueermann. “We have many situations where our dispatchers have resolved incidents without dispatching officers.”
In addition to audio capabilities, Redlands has added another feature recently. City budget restraints have led to fewer lights being kept on at night. Therefore, the department has created the ability to turn on and focus lights where crime might be occurring in the darkness. “It’s relatively inexpensive and very effective,” says Lt. Russ Dalzell.
From Parks to Schools
Another venue has also increased the reach of the police department: schools. The system allowed viewing of video at participating campuses, while providing the ability for the Redlands police to access these cameras. Cameras are able to pan, tilt and zoom, allowing the operators to survey the campus and use the school public address system to intervene if needed. School security and administrators use the system during the day, while the Redlands PD uses the system during off hours.
“We are very proud of the collaborative effort between the school district and the police department, which has resulted in a dramatic reduction in crime on those campuses where video cameras have been installed,” says Dalzell. “High-performance pan/tilt/zoom (PTZ) cameras were installed at strategic locations on several campuses within the Redlands Unified School District in an effort to reduce incidents of vandalism and unauthorized entry onto the campuses after hours. In addition to the cameras, motion detectors and infrared beams are located throughout the campuses, which when tripped, alert police personnel that there’s been an intrusion. Video camera operators then check the campus and determine if a police response is necessary. The school PA system can be used to communicate with intruders.”
Both vandalism and the need for a police response to alarms have been significantly reduced. During school hours, the video camera system allows school security officers to be many places at the same time, which is an effective force multiplier. The collaboration between the school and police department resulted in additional campuses receiving surveillance capabilities as a result of a federal grant.
The complexity of dealing with two independent networks (police department and school) was challenging. “Working with two separate networks and two information technology groups required some innovative thinking between our team and theirs,” says Ray Leblond of Leverage Information Systems, which implemented the surveillance system.
Proactive video surveillance over a large geographical area in real time requires a technology that minimizes latency, while delivering high-quality video. The end-to-end latency of the system deployed in Redlands is below one second. That’s achieved through a distributed architecture and the use of advanced networking capabilities, such as UDP multicast, a function that allows several viewing stations to monitor a single camera without degrading the network bandwidth. Reader beware: Establishing a UDP multicast network for video transportation is complex and requires specialized engineering capabilities.
In a distributed model such as the one deployed in Redlands, each device operates independently. Therefore, the design of the network infrastructure determines the fundamental reliability of the system. Even in a worst-case scenario, a single node failure results in just that one node failing. A network outage, of course, could have a more dramatic impact.
Designing the network using UDP multicast allows virtually unlimited user access to cameras. Leverage has reported more than 100 users accessing approximately 150 cameras in the city of Santa Monica (covering the pier and promenade). These high-end camera nodes do more than just provide video. They can provide advanced video analysis capabilities, such as virtual tripwire, a capability that’s proven very effective at Prospect Park.
Disaster recovery for recorded video is inherent with this type of architecture, and in fact is used in Redlands. The multicast video stream is locally recorded, then recorded independently in the dispatch center. This has proven effective in one incident where access to a camera was lost, but the local recording was able to reveal a hit-and-run incident.
Each camera node is capable of providing various types of video streams. The typical viewing/recording stream is 4 CIF 30 frames per second at 1 MBps. A second stream for each camera is available that produces good situational awareness viewing at 2 CIF 15 frames per second with a data rate of 256 kbps. The second stream works well for such applications as viewing of video by patrol cars or for diagnostic purposes.
Much of the video transverses wireless networks. No-latency, high-quality video requires a 100% duty cycle, so there’s no time to buffer video. In Redlands, the video H.264 and is streamed at 1 Mbps. Wireless networks by nature will drop packets and can be impacted by numerous environmental factors such as radio frequency interference and Fresnal zone infractions. “It was and is our intent to proactively use video surveillance as a key element of our policing methodology,” says Bueermann.
Obtaining Telecommunicator Buy-In
The initial surveillance system included just four cameras in the downtown core area. Dalzell realized that he needed to work with dispatchers so they would see the value of these cameras. There was no better way to do so than to get them involved in an incident. That opportunity came along when dispatchers captured a DUI incident on video. Soon after, a burglary occurred while the dispatcher provided valuable real-time information to the responding officer.
A major expansion of surveillance capabilities in the core downtown area came as surveillance video began to increase the communication between dispatchers and field officers. Video surveillance is so intertwined in the workflow that field officers will often ask the dispatchers what they see with the cameras. It’s common that dispatchers are relaying information from the scene of an incident as the officer is en route.
The next step in the process was the addition of a “surveillance monitoring station” within the dispatch center, and staffing this position with civilians and light-duty officers.
Example: A suspect was seen stumbling to his car by a video operator. The suspect drove away while the operator zoomed in to capture a description of the vehicle and a license plate. An officer was called to respond, and an ongoing dialog of the vehicle’s position was relayed to the responding officer by the dispatcher. In total, five surveillance cameras were used to track this incident, and a DUI arrest was made.
The challenge for all public safety agencies is to accomplish more with less. Improving public safety with constrained budgets requires out-of-the-box thinking and involvement by all stakeholders. Dynamic leadership, cutting-edge technology, innovation and creativity serve the city of Redlands well.
Lt. Russ Dalzell
is retired from the Redlands (Calif.) Police Department (www.ci.redlands.ca.us
is IP surveillance practice manager for Leverage Information Systems, a complete integration firm capable of consultative services, development of requirements, system design and deployment, training and post-installation support. Leverage also develops hardware and software specific for public safety surveillance. Contact Leblond at 800/825-6680.