Hi All,
I really like to thank you for the answers, while I was searching for some
edge detection and clustering algorithms, Moshe came with a simple but
effective solution: use the area to find the diameter!
But I tried Moshe's solution, but I couldn't figure out what you mean with
Hi Bart,
Let's assume that you situation was simpler - you have
a BW (Black and White) image containing circles (in
white) and you need to find the diameter of each
circle (and of course to know how many circles you
have). This can be done with labeling of connected
components. You say that two
Hello Bart!
I took your picture and analysed it with ImageJ.
You can do a particle analysis with the image which measures the required
diameter.
I used the Find Edges method Process-Find Edges and then adjusted the
Brightness/Contrast/maximum
Image-Adjust-Brightness/Contrast.
After this i
Hi,
Maybe this is more a programming questions than a specific R-project question,
but maybe there is someone who can point me in the right direction.
I have a picture of cirkels which I took with a digital camera.
Now I want to use the diameter of the cirkels on the picture for analysis in R.
On 8/23/07, Bart Joosen [EMAIL PROTECTED] wrote:
Maybe this is more a programming questions than a specific R-project
question, but maybe there is someone who can point me in the right direction.
I have a picture of cirkels which I took with a digital camera.
Now I want to use the diameter
Hi,
Maybe this is more a programming questions than a specific R-project question,
but maybe there is someone who can point me in the right direction.
I have a picture of cirkels which I took with a digital camera.
Now I want to use the diameter of the cirkels on the picture for analysis in R.
Hi Bart,
If you only have 36 circles, the fastest way would be to use some image
processing software and measure the circles by hand. One option is to
use ImageJ, which you can download here
http://rsb.info.nih.gov/ij/
Julian
Bart Joosen wrote:
Hi,
Maybe this is more a programming
Hi Bart,
I have never used image processing software in R (I
was doing this with Matlab), but here is what I would
have done algorithmically:
1) convert the picture to gray-scale
2) find a threshold value which separates the circles
from the background and convert your image to black
and white
3)
Hi Bart,
One more comment:
You do not really need the morphological closing to
close the holes inside the circles. Another
possibility is to reverse the black-and-withe picture,
i.e. make the holes and background be 1 and the
circles 0, label the connected components and then
only the component
