Locator The Locator process generates two levels of contours. The coarser Outline Level contour is used to generate hypotheses of potential instances. The finer Detail Level contour is used to confirm the hypotheses and refine the location of the instances. For each level, coarseness values range from 1 to 16. At level 8 for example, the resolution is 8 times lower than an image at full resolution (level 1). Outline Level The Outline Level contour is used to rapidly identify potential instances of the object. l The higher the setting, the coarser the contour resolution.
l To improve search speed, set the Outline Level to the highest value at which contour geometry is still distinctive and stable. Detail Level The Detail Level contour is used to confirm recognition and refine the position of valid instances. l The higher the setting, the coarser the contour resolution. l For images that are not in perfect focus, better results will be obtained with a higher value for the Detail Level. l To obtain high-accuracy object location, it is preferable to use images with sharp edges and set the lowest coarseness value for the Detail Level.
Tracking Inertia (0 - 1) Increasing the Tracking Inertia can help close small gaps and connect contours that would otherwise be broken into smaller sections. Search Based On Outline Level Only Search Based On Outline Level Only restricts the search to using only the Outline Level source contours to search, recognize, and position object instances. Detail Level contours are ignored completely. Setting this to true can increase speed, with a possible loss of accuracy, and with the pos- sibility of detecting false instances.
l An Outline-based search is useful for time-critical applications that do not require a high-positioning accuracy, or that need only to check for presence/absence of objects. l To be effective, this type of search requires clean runtime images that provide high- contrast contours with little or no noise or clutter. ACEUser's Guide, 3.6.x, 18316-000 Rev A Page 563