LocalThickness ..how to add legend?

Can anyone tell me how to add legend after computing localthickness at a binary image stack ?
I have ct dicom data from a fractured rock sample.
I processed the stack (sharpen, thresholding, noise removal, cropping, binarization) and performed successfully the Localthickness (complete process). Stack can be viewed with 3d Viewer plugin, but even though Colorful (LUT) I want to put a legend explaining thickness according to color…
Thanks in advance

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for instance these people done it …but HOW ???

Hi @MHD,

I think you are looking for:
Analyze > Tools > Calibration Bar


Thanks sooo much @lmurphy

It is exactly that: “calibration bar”

something new occured…
When perfoming localthickness plugin on a pic that is already scalled
the calibration bar gives the results in PIXELS instead of set units (microns in my case)
For instant in the pic that follows …white space should be around 1500 microns instead of 23 pixels (as calibration bar says) … (by the way if I add Units in calibration bar it says “Grey Value” …??? )
?? any idea why ?

The calibration bar is designed really for showing how the LUT is applied to the numbers that make up the image. Often, this is the intensity values of the fluorescence detected when an image was taken. These are also called gray values as they are usually captured using a monochrome camera.

In your case, the local thickness plugin returns an image where the values that make up the image are the “thickness” values instead. And these values don’t use your scaling and are in pixels.

To get around this in your case you could multiply the image (using Process > Math > Multiply) by the pixel spacing (49.something) and then re-do the calibration bar.

unfortunately this doesn’t seem to work …
any way thanks again

I drew a very crude facsimile of your image based on your previous post and I think it worked fine?

The only thing I had to do that I didn’t state was after multiplying the image I had to click “reset” on the brightness and contrast panel to change the min and max values so that they now match the now higher values.

hi again …well it seems I am missing something …
# Binarized pic already scaled > execute localthickness> on the resulted pic MULTIPLY with the correct number (so as pixel become Microns lets say) >Image> adjust> brightness/contrast> reset> analyze>tools>calibration bar

nothing happens :cry:

Hmm, do you already have the calibration bar on when you are trying to reset after the multiplication? You can’t change brightness and contrast settings with a calibration bar on.

well I am not sure what happened
after i multyplied the pic with 46 in my case, the result was a B/W pic (no LUT), where callibration bar was the same as before
after running some macros (trying to do a totally different thing) the pic became again colored (LUT) and this time the calibration bar that i decided to add was CORRECT (or at least close to the desired results)

may be something like (reloading??) happened silently /background …who knows … but it worked


Well after multiplying it will look black and white. This happened to me and that’s why the reset of B&C is necessary. This is because post multiplication all your values end up in the “white part” of the LUT based on the current min and max.

I’m glad you have the result you wanted anyway.

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