24 __all__ = [
"GaussianPsfFactory",
"SigmaPerFwhm"]
29 from .singleGaussianPsf
import SingleGaussianPsf
30 from .doubleGaussianPsf
import DoubleGaussianPsf
32 SigmaPerFwhm = 1.0 / (2.0 * math.sqrt(2.0 * math.log(2.0)))
40 """Factory for simple Gaussian PSF models 42 Provides a high-level interface to DoubleGaussianPsf and SingleGaussianPsf 43 by specifying Gaussian PSF model width in FWHM instead of sigma, 44 and supporting computing kernel size as a multiple of PSF width. 45 This makes it suitable for tasks where PSF width is not known in advance. 48 doc=
"Kernel size (width and height) (pixels); if None then sizeFactor is used",
55 doc=
"Kernel size as a factor of fwhm (dimensionless); " 56 "size = sizeFactor * fwhm; ignored if size is not None",
63 doc=
"Minimum kernel size if using sizeFactor (pixels); ignored if size is not None",
70 doc=
"Maximum kernel size if using sizeFactor (pixels); ignored if size is not None",
77 doc=
"Default FWHM of Gaussian model of core of star (pixels)",
83 doc=
"Add a Gaussian to represent wings?",
89 doc=
"wing width, as a multiple of core width (dimensionless); ignored if addWing false",
96 doc=
"wing amplitude, as a multiple of core amplitude (dimensionless); ignored if addWing false",
104 """Compute kernel size and star width as sigma 106 kernel size will be odd unless minSize or maxSize is used and that value is even. 108 @param[in] fwhm: FWHM of core star (pixels); if None then defaultFwhm is used 110 - kernel size (width == height) in pixels 111 - sigma equivalent to supplied fwhm, assuming a Gaussian (pixels) 113 @warning assumes a valid config 118 if self.
size is not None:
129 return size, fwhm * SigmaPerFwhm
132 Config.validate(self)
134 raise RuntimeError(
"minSize=%s > maxSize=%s" % (self.
minSize, self.
maxSize))
137 """Construct a GaussianPsf 139 @param[in] self: an instance of ConfigClass 140 @param[in] fwhm: FWHM of core of star (pixels); if None then self.defaultFwhm is used 141 @return a DoubleGaussianPsf if self.addWing is True, else a SingleGaussianPsf 146 return DoubleGaussianPsf(kernelSize, kernelSize, sigma, wingsSigma, self.
wingAmplitude)
148 return SingleGaussianPsf(kernelSize, kernelSize, sigma)
152 """Make an lsst.pex.config.ConfigurableField 154 def applyWrapper(config, **kwargs):
155 """Construct a Gaussian PSF 157 @param[in] config: an instance of GaussianPsfFactory 159 return config.apply(**kwargs)
def apply(self, fwhm=None)
def computeSizeAndSigma(self, fwhm=None)