How to enlarge ROI imagej macro

Question

I would like to enlarge several rois with the following loop:

counts=roiManager("count");
 for(i=0; i<counts; i++) {
    roiManager("Select", i);
    run("Enlarge...", "enlarge=10");
 }

However, I can’t figure out, what’s wrong with this macro.

Answer 1

Your code enlarges every ROI by 10 pixels, but does not store the new ROI in the ROI manager. You are missing the roiManager("Update"); command, which you get when running the macro recorder while clicking the Update button in the ROI Manager window.

counts=roiManager("count");
for(i=0; i<counts; i++) {
    roiManager("Select", i);
    run("Enlarge...", "enlarge=10");
    roiManager("Update");
}