http://arxiv.org/abs/1705.01109
An unbiased estimator for the ellipticity of an object in a noisy image is given in terms of the image moments. Three assumptions are made: i) the pixel noise is normally distributed, although with arbitrary covariance matrix, ii) the image moments are taken about a fixed centre, and iii) the point-spread function is known. The relevant combinations of image moments are then jointly normal and their covariance matrix can be computed. A particular estimator for the ratio of the means of jointly normal variates is constructed and used to provide the unbiased estimator of the ellipticity. Furthermore, an unbiased estimate of the covariance of the new estimator is also given.
N. Tessore
Thu, 4 May 17
49/54
Comments: 7 pages, comments welcome
You must be logged in to post a comment.