Re: particles missed by Particle Analysis

Posted by Gabriel Landini on Feb 18, 2009; 8:56am
URL: http://imagej.273.s1.nabble.com/Re-IMAGEJ-Digest-14-Feb-2009-to-15-Feb-2009-2009-45-tp3693650p3693654.html

On Wednesday 18 February 2009, Glen MacDonald wrote:
> Analyze Particles correctly identifies about 25 larvae in each frame
> of the timelapse.
> But, 3-5 larvae are not measured in each frame.

Unless you post pictures with examples and code, knowing what is going on will
be just guesswork.

> The display of the best fit ellipses and numbering the thresholded
> larvae by result line identifies the missed larvae.  Individual
> measurement of the missed larvae indicates they meet all criteria for
> particle analysis.  In some instances, a larva may not have changed
> position for several frames, yet will have been measured in some
> frames, but not in others.

There is a tendency to using only the built in threshold for object
segmentation. While it works for many instances, it is by no means the optimal
nor the most appropriate method for all possible cases. Perhaps you colleague
should try other segmentation algorithms.

G.