iCys User Guide

Using the iNovator Toolkit iNovator-specific Protocol Modules
➣ To perform a morphological erode, dilate, open or close:
1. Click to open the module. For all of these functions, a similar dialog box displays.
2. In the Structuring Element panel, specify the shape and size of the kernel you
want to morph.
Watershed Module
The Watershed module performs watershed segmentation. Watershed segmentation is
a process of using erosion and dilation (discussed in “Binary Image Filtering—Erode,
Dilate, Open, Close Modules” on page B-15) on a Euclidean distance map to separate
closely spaced or overlapping events. A grayscale image is generated from the binary
image using a Euclidean distance map technique. A grayscale pixel value is generated
for the positive pixels based on the distance of that pixel from the nearest background
pixel. Localized peaks (called Ultimate Eroded Points or UEPs) are identified and the
image eroded back to these UEPs. The image is then dilated until the positive pixels
meet the original background boundary or until a second, dilating UEP is encountered.
The dilation is stopped short of joining the UEPs, thus developing the intended
separation. Various parameters may be set by the user to affect how this process
proceeds.
Tip: To create a binary image for input to the Watershed module, call the
Threshold module before calling the filtering module. The Threshold
module produces binary output.
Figure B-12 shows a different image after watershed segmentation.
B-18 iCys Research Imaging Cytometer User Guide Revision B