Estimating landmarks on 2D images of beetle mandibles
Date issued
2016
Journal Title
Journal ISSN
Volume Title
Publisher
Václav Skala - UNION Agency
Abstract
Studying links between phenotype/genotype and agricultural practices is one of the main topics in agronomy
research. Phenotypes can be characterized by informations like age, sex of animals/plants and more and more
often with the help of image analysis of their morphology. From now, getting good quality of images for numerous
individuals is easy but that leads to design automatic procedures to replace manual exploration of such amount of
images. Several bottlenecks have been identified to analyze automatically images. One of them is segmentation
of selected area and/or shapes, and another well-known one is setting automatically morphometric landmarks.
Landmarks are points on the object which can be used to identify or to classify the objects.
It exists a lot of methods to experiment landmarks setting, depending on the image contents. This work has been
initiated by using the article of Palaniswamy et al. "Automatic identification of landmarks in digital images"[6].
They proposed a method based on calculus of a probabilistic Hough transform coupling to a template matching
algorithm. They applied their method to the Drosophilia wings. In our study, we have gotten a set of 291 beetles
. For each one 2D images of 5 different parts of their anatomy have been taken: mandibles left and right, head,
pronotum and elytra. The first part of the project was to test how the Palaniswamy’s method could be used to
analyze them. We have implemented all the required algorithms to compute positions of mandibles landmarks and
compared the obtained results to landmarks which have been manually set by biologists. We will see that even
positions automatically obtained are not fully precised, if we used centroid size to characterize mandibles, the size
computed from automatic landmarks is closed to this one computed from the manual ones. Future works will focus
on definition of a semi-landmarks procedure which would add some features as the measure of the curve between
two landmarks.
Description
Subject(s)
identifikace orientačních bodů, pravděpodobnostní transformace hloubky, morfometrie čeleďě chrobáka
Citation
WSCG 2016: poster papers proceedings: 24th International Conference in Central Europe on Computer Graphics, Visualization and Computer Visionin co-operation with EUROGRAPHICS Association, p. 75-78.