2 February 2009 Separation of limb and terminator on apparent contours of solar system small bodies
Author Affiliations +
Segmentation of contours and silhouettes is a recurrent topic in image recognition and understanding. In this paper we describe a new method used to divide in two parts (the limb and the terminator) the apparent silhouette of an irregular astronomical body illuminated by a unique source, the Sun. One of the main objectives of the asteroids and comets flyby is the detailed 3D reconstruction of such bodies. However the number of images obtained during a flyby is limited, as well as the number of viewing geometries. In the 3D reconstruction we must consider not only the camera motion but also the free rotation of the body. The local brightness variations in the image vary with the rotation of the body and with the changing body-camera distance. The topography at the surface of the body can vary from very smooth to highly chaotic. In the shape from silhouette 3D reconstruction methods, limb profiles are used to retrieve the visual hull of the body. It is therefore required to be able to separate the limb profiles from the terminator ones. In this communication, we present a new method to perform this task based on the local measurement of the contour smoothness, which we define here as "activity". Developed in the framework of the Rosetta mission our method has been tested on a large set of asteroid and comet images taken during interplanetary missions. It looks robust to magnification and enlightenment changes
© (2009) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
A. Llebaria, A. Llebaria, L. Jorda, L. Jorda, O. Groussin, O. Groussin, G. Gesquiere, G. Gesquiere, P. Lamy, P. Lamy, } "Separation of limb and terminator on apparent contours of solar system small bodies", Proc. SPIE 7246, Computational Imaging VII, 724610 (2 February 2009); doi: 10.1117/12.804725; https://doi.org/10.1117/12.804725

Back to Top