Path: SpacecraftEstimation/StellarAttDet
% Finds the centroid given intensities on n pixels and their coordinates.
This uses the center of mass method. The center of mass will have
larger errors if the width of the region of interest goes outside
the pixel mask. Generally, star measurements on the edge will not
be reliable due to optical errors so should be discarded if you have
enough stars that for than n pixels from the edges.
x is defined in the column direction, y in the row direction.
iPSF is in the same units as the intensity of the pixel map.
Type StarCentroidCOM for a demo which will draw the centroid and the
intensity map. With one output it will return [x0;y0]
Since version 2014.1.
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Form:
[x0, y0, iC] = StarCentroidCOM( p, threshold, nROI, doPlot )
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Inputs
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p (:,:) Pixel map
threshold (1,1) Threshold indicating a star is present
nROI (1,1) Size of region of interest (pixels)
doPlot (1,1) Specify true to generate the demo plot
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Outputs
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x0 (1,:) x centroid or (3,:) [x0;y0;iPSF]
y0 (1,:) y centroid
iC (1,:) Total intensity of the centroid
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Reference: M. Knutson and D. Miller, "Fast Star Tracker Centroid
Algorithm for High Performance CubeSat with Air Bearing
Validation," June 2012 MIT SSL # 5-12
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Common: General/DeBlankLT Common: Graphics/NewFig Common: Graphics/PltStyle Common: Graphics/XLabelS Common: Graphics/YLabelS Common: Graphics/ZLabelS Imaging: PSFUtils/ImagerPSF Imaging: PSFUtils/RHSGaussianPSF
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