- sunkit_image.trace.occult2(image, nsm1, rmin, lmin, nstruc, ngap, qthresh1, qthresh2)#
Implements the Oriented Coronal CUrved Loop Tracing (OCCULT-2) algorithm for loop tracing in images.
sunpy.map.GenericMap) – Image in which loops are to be detected.
int) – Low pass filter boxcar smoothing constant.
int) – The minimum radius of curvature of the loop to be detected in pixels.
int) – The length of the smallest loop to be detected in pixels.
int) – Maximum limit of traced structures.
int) – Number of pixels in the loop below the flux threshold.
float) – The ratio of image base flux and median flux. All the pixels in the image below
qthresh1 * medianintensity value are made to zero before tracing the loops.
float) – The factor which determines noise in the image. All the intensity values between
qthresh2 * medianare considered to be noise. The median for noise is chosen after the base level is fixed.
list– A list of all loop where each element is itself a list of points containing
ypixel coordinates for each point.
Markus J. Aschwanden, Bart De Pontieu, Eugene A. Katrukha. Optimization of Curvi-Linear Tracing Applied to Solar Physics and Biophysics. Entropy, vol. 15, issue 8, pp. 3007-3030 https://doi.org/10.3390/e15083007