Posted by
Ghislain Bonamy on
May 11, 2009; 11:09pm
URL: http://imagej.273.s1.nabble.com/Convert-a-set-of-points-into-an-ROI-tp3692520p3692524.html
Curtis,
Thanks for the reply. Unfortunatelly, most of the forms are not convex, but all of the points lie on the Hull. I have attached a zip file,
ROI.zip, that contains: a picture showing the different ROI (different colors=different objects), and the coordinates for thes objects, which provide the outline of these objects. The x;y vaues are separted by ';' and the different points are separated by ','. This is not the final schema for the ROI format, but it should give you an idea about what I have cooking.
So the problem at hand is to be able to either order the points for each objects in an order that is suitable for the registration of the ROI. Could anyone explain what are the different type of ROI? In particular what is polyline? This might be the best type to use, but I do not know what it represents.
I think that one garante with the ROI outputed, is that for each pixels provided, there are only 2 adjacent points (ie, if you imagin a pixel, it can only be surounded by 8 pixels, since we are in a 2D space). So one strategy, would be to take one point and then look in this 8possibly surounding pixels which one is present. when this is done, keep iterating until the loop is closed (ie, all pixels around are blank or already in the ROI).
The only problem is that perhaps in the future some objects may have holes in them for instance.
My need for ROI, is mainly for display purposes, although perhaps, in the future, it might be used to skip some steps for the image analysis.
Any help would be most appreciated!
Best,
Ghislain