PointSourceExtractor

Overview

PointSourceExtractor provides functionality for identifying and characterizing point sources in an image. The source extraction algorithm is described here:

https://iopscience.iop.org/article/10.1088/1538-3873/ab7ee8

Constructors

public PointSourceExtractor() The default constructor for the class object, used when an image is to be examined for sources.

public PointSourceExtractor(double[] XCoords, double[] YCoords) The constructor for the class object used when an image already has a given list of coordinate locations for sources in the image. Use overload of Extract_Sources referencing the objects own centroids to determine source characteristics at the coordinate locations.

public PointSourceExtractor(JPFITS.FITSBinTable BinTablePSE) The constructor for the class object based on a PointSourceExtractor saved from another session.

Methods

public void Extract_Sources(double[,] image, double pix_saturation, double pix_min, double pix_max, double kernel_min, double kernel_max, bool threshholds_as_SN, int kernel_radius, int source_separation, bool auto_background, string kernel_filename_template, bool[,]? ROI_region, bool show_waitbar) Searches for sources within a 2D image array.

• image The 2D image array to find sources in. pix_saturation The saturation threshold of of the image pixels, for finding saturation islands. Set equal to zero (0) if not needed.
• pix_min The minimum pixel threshold value (or SN) to consider a potential source.
• pix_max The maximum pixel threshold value (or SN) to consider a potential source.
• kernel_min The minimum kernel pixel sum threshold value (or SN) to consider a potential source.
• kernel_max The maximum kernel pixel sum threshold value (or SN) to consider a potential source.
• threshholds_as_SN Treat the thresholds as Signal to Noise instead of pixel values.
• kernel_radius The radius (pixels) of the kernel to find sources within. Secondary sources within the radius will be ignored.
• source_separation The separation (pixels) between sources. Only the brightest source within the separation radius is kept.
• auto_background Automatically determine the local background for potential sources. Not required if background is known to be zeroed, but should have no effect if used in this case.
• kernel_filename_template The template full file name for the kernels to be saved. Sources will be numbered sequentially. Pass empty string for no saving.
• ROI_region A boolean array of valid area to examine. Pass null or array of equal dimension to source image all true for entire image search.
• show_waitbar Show a cancellable wait bar.

public void Extract_Sources(double[,] image, double[] XCoords, double[] YCoords, int kernel_radius, bool auto_background, string kernel_filename_template) Determines centroids and other kernel information for known sources at given coordinates.

• image The 2D image array containing the known sources to extract.
• XCoords The x-axis coordinates of the sources. These can be PSE.Centroids_X.
• YCoords The y-axis coordinates of the sources. These can be PSE.Centroids_Y.
• kernel_radius The radius (pixels) of the kernel to centroid.
• auto_background Automatically determine the local background for potential sources. Not required if background is known to be zeroed, but should have no effect if used in this case.
• kernel_filename_template The template full file name for the kernels to be saved. Sources will be numbered sequentially. Pass empty string for no saving.