Gimp script: Selection area finder

[isomage]

Note that the histogram function doesn't work on color-indexed images. The script currently will only work in RGB mode, though I may add support for grayscale later.

[blocus]

Hi,

I follow your instruction isoman but once i installed the file and i select perimeter and area , Gimp heralds me 2 errors
such as : Calling error for procedure 'gimp-image-add-layer'
and execution error for Area and perimeter : error procedure execution of .... failed on invalid input arguments : image '... ' is of type 'gray', but an image of type 'rgb' is expected

[Redrobes]

Sounds like you should at least start by upping the color palette from 8 bit greyscale to full 24bit RGB. Not sure about the other one but maybe they are related.

[blocus]

Thx a lot for your fast answer, I selected the RGB mode, and then it assest the perimeter as well as the area , however i found that the value are wrong compare to the reality.
Indeed I'm interesting in the area, and when i compare the number of pixel from the histogram option and the percentage of area ( %*nm of pixel) the value are similar. But when i converted with the real scale , in my case i use 150 micrometers , so I multiplicate the number of pixel per 150*10e-3 and it gives wrong estimation , do you have an idea to assess the superficie with the number of pixel ?
Merci Beaucoup
:=)