Saving project, with multiple areas, to get them later



Hi, I just discovered fiji in this post:

I installed just minutes ago.

I have to measure multiple bedrooms, kitchens, bathrooms, dinningroom, etc. in a building blueprint/plan. I have the blueprint scanned in JPEG and I managed to “calibrate” the scale and tested with a polygon I knew the real surface and managed to make fiji to give me the proper surface in square-meters for that polygon.

But as soon as I create polygon number 2, the polygon number 1 just disappears.


a) Is there a way so I can perimeter all the rooms I’m interested in and when I do “kitchen” I do not loose “bathroom” for example?

b) Is there a way to save the “project” file so I can just perimeter today, save it, and measure tomorrow? In the “save” I felt it saves like image formats, IDK what’s the native format I should use to preserve my polygons.


You can collect all ROI’s (selections) in the ROI Manager. For a description see here:

With the ROI Manager you can save and restore all selections, measure them, etc.


Maybe I’m too newbie to Fiji… em… I’m affraid I don’t know what is a ROI…


A ROI is simply a Region Of Interest (your selection)


Ah wow! Okey, that clarifies everything hehehe. Thanks so much, will try your tips!


Just select your polygon and press ‘t’ as a key shortcut and the magic happens.
You will find a lot of information about the ROI Manager in the forum archives.
And I’m sure you will find some YouTube tutorials.

By the way…If you store the image as a *tif the current ROI’s are stored, too (multiple ROI’s can be drawn by holding the SHIFT key!).

In ImageJ ROI’s can also be combined, etc. and some shortcuts for this operations are available, too.
Also in the ROI Manager (see the manual!)

See also the chapter about the selections to add or delete a point from a ROI, etc.:


Thanks for the support. It all did the trick:

  • Read all the documentation you passed me, plus many of the related links to other doc pages from the doc itself.
  • I finally managed to setup the proper scale (counting plan scale x scan dpi) and then select multiple rooms in the same flat
  • And saved them into the TIFF so it remains there for further editing.
  • I managed to play well with “overlay to ROI manager” and “from”.
  • I then managed to just close all, load the TIFF, which in addition loads the overlay and my scale settings, and just tranfer to ROI manager and do “measure” and get the real measures.

So thanks!