Calculate area and diameter
On 01/22/2012 01:10 PM, Dutch-User wrote:
Hi everyone. In my collection of pictures, I found GIMP useful and easy to measure the diameter of a near-round coloured object. However, since the objects are not exactly round, I have to measure a few times and than guess for the average diameter. Now I've seen there's a way to select these objects by the colour they have. Does anybody know if there's an easy way to have GIMP tell me the overall area of the object, and the mean diameter?
Thanks!
A while ago I calculated area by creating a transparent layer and
painting with a brush the locations that I wanted to include in the
area. Then using GIMP's histogram (color>Info>histogram), I got a pixel
count for that new layer. (Side note, make sure you have the right layer
selected in the layers dialog)
Then I used a proportion ( Pixels:Inches ) that I got from a scale in
the image to calculated area.
There might be a easier way to calculate area since you have simple
shapes, but this worked perfectly for me, because my shapes were highly
irregular and needed human interaction to determine what should be
measured and what shouldn't be.
HTH,
-Stefan Maerz