ForcedPeakCentroidPlugin

class lsst.meas.base.ForcedPeakCentroidPlugin(config, name, schemaMapper, metadata)

Bases: ForcedPlugin

Record the highest peak in a source footprint as its centroid.

This is of course a relatively poor measure of the true centroid of the object; this algorithm is provided mostly for testing and debugging.

This is similar to SingleFramePeakCentroidPlugin, except that transforms the peak coordinate from the original (reference) coordinate system to the coordinate system of the exposure being measured.

Parameters

configForcedPeakCentroidConfig

Plugin configuraion.

namestr

Plugin name.

schemaMapperlsst.afw.table.SchemaMapper

A mapping from reference catalog fields to output catalog fields. Output fields are added to the output schema.

metadatalsst.daf.base.PropertySet

Plugin metadata that will be attached to the output catalog.

Methods Summary

getExecutionOrder()	Get the relative execution order of this plugin.
getTransformClass()	Get the measurement transformation appropriate to this plugin.
measure(measRecord, exposure, refRecord, refWcs)	Measure the properties of a source given an image and a reference.

Methods Documentation

classmethod getExecutionOrder()

Get the relative execution order of this plugin.

Must be reimplemented as a class method by concrete derived classes.

static getTransformClass()

Get the measurement transformation appropriate to this plugin.

This returns a subclass of transforms.MeasurementTransform, which may be instantiated with details of the algorithm configuration and then called with information about calibration and WCS to convert from raw measurement quantities to calibrated units. Calibrated data is then provided in a separate output table.

Notes

By default, we copy everything from the input to the output without transformation.

measure(measRecord, exposure, refRecord, refWcs)

Measure the properties of a source given an image and a reference.

Parameters

exposurelsst.afw.image.ExposureF

The pixel data to be measured, together with the associated PSF, WCS, etc. All other sources in the image should have been replaced by noise according to deblender outputs.

measRecordlsst.afw.table.SourceRecord

Record describing the object being measured. Previously-measured quantities will be retrieved from here, and it will be updated in-place with the outputs of this plugin.

refRecordlsst.afw.table.SimpleRecord

Additional parameters to define the fit, as measured elsewhere.

refWcslsst.afw.geom.SkyWcs or lsst.afw.geom.Angle

The coordinate system for the reference catalog values. An Angle may be passed, indicating that a local tangent WCS should be created for each object using the given angle as a pixel scale.

Notes

In the normal mode of operation, the source centroid will be set to the WCS-transformed position of the reference object, so plugins that only require a reference position should not have to access the reference object at all.