Re: RoiManager multiple selection

Posted by Wayne Rasband on Jun 11, 2009; 2:19am
URL: http://imagej.273.s1.nabble.com/RoiManager-multiple-selection-tp3692174p3692175.html

On Jun 10, 2009, at 7:49 PM, Eirinn Mackay wrote:

> Hi all,
> Is it possible to select multiple ROIs programmatically? I'd like  
> to select all that match a certain characteristic, draw them to the  
> image with one foreground color, then select other ROIs and draw  
> them with a different foreground color.
> I am writing a python script so I'm using the API, but I can always  
> call a macro command if necessary.
>
> The API describes a function - select(int index, boolean  
> shiftKeyDown, boolean altKeyDown) - but those boolean arguments  
> don't appear to work. If either of them are true, nothing can be  
> selected.
> I've tried selecting each ROI in turn and drawing it, but this is  
> prohibitively slow.
>
> Any ideas?

Use the getRoisAsArray() method to get all the ROIs and then use the  
drawPixels() method to draw selected ROIs in the array. Here is a  
JavaScript example that draws half the ROIs in the ROI Manager in red  
and the other half in blue.

    manager = RoiManager.getInstance();
    if (manager==null)
       IJ.error("ROI Manager is not open");
    rois = manager.getRoisAsArray();
    img = IJ.getImage();
    ip = img.getProcessor();
    for (i=0; i<rois.length; i++) {
       if (i<rois.length/2)
           ip.setColor(Color.red);
       else
           ip.setColor(Color.blue);
       rois[i].drawPixels(ip);
    }
    img.updateAndDraw();

-wayne