Solution No. 4: Speed dome with integrated infrared
Integrating infrared illumination directly onto the pan-tilt mechanism ensures that light is directed to the same area being monitored by the camera. This technique produces the advantage of always having infrared illumination available for the camera, regardless of its position. Essentially, the technique achieves virtual 360º coverage without wasting any light on areas that don’t need illumination.
Some dome cameras use frame integration techniques to overcome the challenge of obtaining clear images in dark scenes. Because frame integration typically involves slowing down shutter speed and combining frames, it is acceptable only in a limited number of applications. Frame integration is generally not effective for imaging of moving objects, resulting in motion blur and loss of detail. For example, if an intruder moves through these areas during the dome’s ‘tour’, he will only be recorded as a blur, and vital information and detail will be missed.
The problem of motion blur caused by frame integration is easily solved by simply providing more light. With the application of infrared illumination, the camera determines that there is sufficient light on scene and therefore does not revert to frame integration mode.
It is worthwhile to note that each of the strategies above applies equally to infrared illumination and white light illumination, which is often specified in applications where it is important to have color surveillance video at night. For additional details on white light illuminators, refer to Extreme’s White Light product literature.
Willem Ryan is the product marketing manager for Extreme CCTV, a member of the Bosch Group located in
Better Use of Video Motion Detection & Analytics
Like all software, video analytics requires valid data to ensure proper function. Without valid data for the algorithms to process, even the most advanced video analytic software will fail. The use of infrared illumination brings important functional benefits to video motion detection and video analytics. Infrared illumination also eliminates video degradation (which causes a choppy image) caused by frame integration.
Active-infrared is an enabling technology for the nighttime function of video analytics. Active-infrared illumination eliminates the poorly-lit, noisy images typically seen under low light conditions. These noisy images, which represent poor data, wreak havoc on video analytic software and render them ineffective. However, the addition of active-infrared improves the images dramatically, enabling high resolution performance. Similarly, other video-based functions commonly found on DVRs, NVRs and digital video management systems will also fail in the dark. These functions - which include video motion detection, automatic alarms, false alarm suppression, video motion searching and event recording - all require high-signal, low-noise images to work properly and perform optimally when used with infrared illumination.