Instead of starting a new thread on the same subject, I’d like to revive @Alexander’s original question, make a few observations and finally issue a request. The question raised by Alexander and ably replied to by @Benoit and @twagner (I should note that I’ve been in touch with both of them) is all too familiar to people involved in the characterization of chopped-fiber-reinforced thermoplastic composites, that is, what’s the average length and the length distribution of the brittle carbon, glass or mineral fibers after various high-shear processing steps? Both these characteristics greatly affect the modulus, strength and fatigue properties of the finished product.
While the three offered solutions offer partial answers to the question, none of them seem to be able to deal with multiple instances of such straight fiber segments touching i crossing, often forming groups of more than 2 fibers. The common solution is either treat such groups as one larger Feret diameter fiber (Analyze Particles), which biases the calculated distribution towards the longer objects, or eliminating them from the calculation (rods_analysis or Ridge Detection.) That latter case biases the calculated distribution towards the shorter length values, since longer fibers have a higher probability to cross or touch other objects. Finally, the available reports do not include the Feret diameter (effectively, the max and min length of the objects.
There is one special characteristic of all these fibrous objects that makes them different from many other fibrous or wormy objects analyzed by others, that is, they are all straight (linear) objects with easily determined end points.
I’m not a programmer, but it seems to me that the problem described above is common enough and its solution would greatly benefit numerous researchers and technicians involved in the characterization of these very important materials. The enhanced plugin would have to combine the ability of the several existing utilities (Analyze Particles, Ridge Detection and rods_analysis_v1.1.py) to isolate and measure the full length (and maybe width) of numerous crossed linear objects (they may form figures similar to upper case letters A, C, E, F, H, K, L, M, N, O, P, R, S, T, U, V, X, Y and Z (the most often seen are bolded; the other figures are seldom seen in practice.), generate a Report exactly like the one associated with the Analyze Particle method, including the chart. The only additional column might mark the type of overlap detected (a letter?).
So, my question is, how does one get people capable of writing such a plugin interested in this extension? I can cite more than 500 papers dealing with this quirky issue which seems to me to be easier to resolve than a bunch of wiggly C. elegans worms: https://goo.gl/sTBWwO I wish I knew Java and Python…