Detection
Preprocessors
The image enhancement pre-processors enhance the target(s). The action of the image enhancement pre-processor is to increase the target intensity and decrease the background intensity.
There are three categories of pre-processor:
- Positive Contrast - enhance positive contrasts (White Hot)
- Negative Contrast - enhance negative contrasts (Black Hot)
- Bipolar - enhance either positive of negative contrasts
The following pre-processors are available:
- Grey pre-processor - Performs no enhancement and is used with correlation algorithms.
- Statistical pre-processor - Enhances targets with both positive and negative components
- White-Hot pre-processor - Enhances positive contrast targets
- Black-Hot pre-processor - Enhances negative contrast targets
Moving Target Detection
The Moving Target Detection (MTD) acquisition algorithm extracts objects from the scene which are moving independently in relation to the background. This is achieved by tracking the background motion using a SceneLock process and aligning the background with a reference image. Any differences between the reference image and the current aligned image are assumed to be moving targets. The MTD algorithm has a variable sensitivity setting. A high sensitivity setting will allow slow, low contrast targets to be detected, but may also produce many false alarms. Lower sensitivity settings will reduce the frequency of false alarms, but will potentially miss detections of low contrast or slow moving targets.
The MTD algorithm requires a structured scene to allow the SceneLock process to track the background motion. The detection process can be configured to detect only targets of a certain size, travelling at a certain speed, or only targets that have moved by a particular distance. The MTD process is not currently implemented as a tracking algorithm. It is recommended that when MTD is used to acquire a target, the phase correlator is used for tracking.
