AssembleCoaddTask¶
- class lsst.drp.tasks.assemble_coadd.AssembleCoaddTask(*args, **kwargs)¶
Bases:
CoaddBaseTask
,PipelineTask
Assemble a coadded image from a set of warps.
Each Warp that goes into a coadd will have its flux calibrated to nJy. WarpType may be one of ‘direct’ or ‘psfMatched’, and the boolean configs
config.makeDirect
andconfig.makePsfMatched
set which of the warp types will be coadded. The coadd is computed as a mean with optional outlier rejection. Criteria for outlier rejection are set inAssembleCoaddConfig
. Finally, Warps can have bad ‘NaN’ pixels which received no input from the source calExps. We interpolate over these bad (NaN) pixels.AssembleCoaddTask
uses several sub-tasks. These areScaleZeroPointTask
create and use an
imageScaler
object to scale the photometric zeropoint for each Warp (deprecated and will be removed in DM-49083).InterpImageTask
interpolate across bad pixels (NaN) in the final coadd
You can retarget these subtasks if you wish.
- Raises:
- RuntimeError
Raised if unable to define mask plane for bright objects.
Notes
Debugging:
AssembleCoaddTask
has no debug variables of its own. Some of the subtasks may supportlsstDebug
variables. See the documentation for the subtasks for further information.Attributes Summary
Methods Summary
applyAltMaskPlanes
(mask, altMaskSpans)Apply in place alt mask formatted as SpanSets to a mask.
assembleMetadata
(coaddExposure, warpRefList, ...)Set the metadata for the coadd.
assembleOnlineMeanCoadd
(coaddExposure, ...)Assemble the coadd using the "online" method.
assembleSubregion
(coaddExposure, bbox, ...)Assemble the coadd for a sub-region.
Empty (clear) the metadata for this Task and all sub-Tasks.
filterWarps
(inputs, goodVisits)Return list of only inputRefs with visitId in goodVisits ordered by goodVisit.
Convenience method to provide the bitmask from the mask plane names
Get metadata for all tasks.
Get the task name as a hierarchical name including parent task names.
getName
()Get the name of the task.
Get a dictionary of all tasks as a shallow copy.
getTempExpDatasetName
([warpType])Return warp name for given warpType and task config
makeField
(doc)Make a
lsst.pex.config.ConfigurableField
for this task.makeSubtask
(name, **keyArgs)Create a subtask as a new instance as the
name
attribute of this task.prepareInputs
(refList, coadd_bbox[, ...])Prepare the input warps for coaddition by measuring the weight for each warp.
prepareStats
([mask])Prepare the statistics for coadding images.
processResults
(coaddExposure[, ...])Interpolate over missing data and mask bright stars.
run
(skyInfo, *, warpRefList, ...[, ...])Assemble a coadd from input warps.
runQuantum
(butlerQC, inputRefs, outputRefs)Do butler IO and transform to provide in memory objects for tasks
run
method.setBrightObjectMasks
(exposure, brightObjectMasks)Set the bright object masks.
setInexactPsf
(mask)Set INEXACT_PSF mask plane.
timer
(name[, logLevel])Context manager to log performance data for an arbitrary block of code.
Attributes Documentation
Methods Documentation
- applyAltMaskPlanes(mask, altMaskSpans)¶
Apply in place alt mask formatted as SpanSets to a mask.
- Parameters:
- mask
lsst.afw.image.Mask
Original mask.
- altMaskSpans
dict
SpanSet lists to apply. Each element contains the new mask plane name (e.g. “CLIPPED and/or “NO_DATA”) as the key, and list of SpanSets to apply to the mask.
- mask
- Returns:
- mask
lsst.afw.image.Mask
Updated mask.
- mask
- assembleMetadata(coaddExposure, warpRefList, weightList, psfMatchedWarpRefList=None)¶
Set the metadata for the coadd.
This basic implementation sets the filter from the first input.
- Parameters:
- Raises:
- AssertionError
Raised if there is a length mismatch.
- assembleOnlineMeanCoadd(coaddExposure, warpRefList, imageScalerList, weightList, altMaskList, statsCtrl, nImage=None)¶
Assemble the coadd using the “online” method.
This method takes a running sum of images and weights to save memory. It only works for MEAN statistics.
- Parameters:
- coaddExposure
lsst.afw.image.Exposure
The target exposure for the coadd.
- warpRefList
list
List of dataset handles (data references) to warp.
- imageScalerList
list
List of image scalers. Deprecated and will be removed after v29 in DM-49083.
- weightList
list
List of weights.
- altMaskList
list
List of alternate masks to use rather than those stored with warp, or None. Each element is dict with keys = mask plane name to which to add the spans.
- statsCtrl
lsst.afw.math.StatisticsControl
Statistics control object for coadd.
- nImage
lsst.afw.image.ImageU
, optional Keeps track of exposure count for each pixel.
- coaddExposure
- assembleSubregion(coaddExposure, bbox, warpRefList, imageScalerList, weightList, altMaskList, statsFlags, statsCtrl, nImage=None)¶
Assemble the coadd for a sub-region.
For each coaddTempExp, check for (and swap in) an alternative mask if one is passed. Remove mask planes listed in
config.removeMaskPlanes
. Finally, stack the actual exposures usinglsst.afw.math.statisticsStack
with the statistic specified by statsFlags. Typically, the statsFlag will be one of lsst.afw.math.MEAN for a mean-stack orlsst.afw.math.MEANCLIP
for outlier rejection using an N-sigma clipped mean where N and iterations are specified by statsCtrl. Assign the stacked subregion back to the coadd.- Parameters:
- coaddExposure
lsst.afw.image.Exposure
The target exposure for the coadd.
- bbox
lsst.geom.Box
Sub-region to coadd.
- warpRefList
list
List of dataset handles (data references) to warp.
- imageScalerList
list
List of image scalers. Deprecated and will be removed after v29 in DM-49083.
- weightList
list
List of weights.
- altMaskList
list
List of alternate masks to use rather than those stored with warp, or None. Each element is dict with keys = mask plane name to which to add the spans.
- statsFlags
lsst.afw.math.Property
Property object for statistic for coadd.
- statsCtrl
lsst.afw.math.StatisticsControl
Statistics control object for coadd.
- nImage
lsst.afw.image.ImageU
, optional Keeps track of exposure count for each pixel.
- coaddExposure
- filterWarps(inputs, goodVisits)¶
Return list of only inputRefs with visitId in goodVisits ordered by goodVisit.
- Parameters:
- inputs
list
ofDeferredDatasetRef
List of
lsst.pipe.base.connections.DeferredDatasetRef
with dataId containing visit.- goodVisit
dict
Dictionary with good visitIds as the keys. Value ignored.
- inputs
- Returns:
- filterInputs
list
[lsst.pipe.base.connections.DeferredDatasetRef
] Filtered and sorted list of inputRefs with visitId in goodVisits ordered by goodVisit.
- filterInputs
- getBadPixelMask()¶
Convenience method to provide the bitmask from the mask plane names
- getFullMetadata() TaskMetadata ¶
Get metadata for all tasks.
- Returns:
- metadata
TaskMetadata
The keys are the full task name. Values are metadata for the top-level task and all subtasks, sub-subtasks, etc.
- metadata
Notes
The returned metadata includes timing information (if
@timer.timeMethod
is used) and any metadata set by the task. The name of each item consists of the full task name with.
replaced by:
, followed by.
and the name of the item, e.g.:topLevelTaskName:subtaskName:subsubtaskName.itemName
using
:
in the full task name disambiguates the rare situation that a task has a subtask and a metadata item with the same name.
- getFullName() str ¶
Get the task name as a hierarchical name including parent task names.
- Returns:
- fullName
str
The full name consists of the name of the parent task and each subtask separated by periods. For example:
The full name of top-level task “top” is simply “top”.
The full name of subtask “sub” of top-level task “top” is “top.sub”.
The full name of subtask “sub2” of subtask “sub” of top-level task “top” is “top.sub.sub2”.
- fullName
- getName() str ¶
Get the name of the task.
- Returns:
- taskName
str
Name of the task.
- taskName
See also
getFullName
Get the full name of the task.
- getTaskDict() dict[str, weakref.ReferenceType[lsst.pipe.base.task.Task]] ¶
Get a dictionary of all tasks as a shallow copy.
- Returns:
- taskDict
dict
Dictionary containing full task name: task object for the top-level task and all subtasks, sub-subtasks, etc.
- taskDict
- getTempExpDatasetName(warpType='direct')¶
Return warp name for given warpType and task config
- classmethod makeField(doc: str) ConfigurableField ¶
Make a
lsst.pex.config.ConfigurableField
for this task.- Parameters:
- doc
str
Help text for the field.
- doc
- Returns:
- configurableField
lsst.pex.config.ConfigurableField
A
ConfigurableField
for this task.
- configurableField
Examples
Provides a convenient way to specify this task is a subtask of another task.
Here is an example of use:
class OtherTaskConfig(lsst.pex.config.Config): aSubtask = ATaskClass.makeField("brief description of task")
- makeSubtask(name: str, **keyArgs: Any) None ¶
Create a subtask as a new instance as the
name
attribute of this task.- Parameters:
- name
str
Brief name of the subtask.
- **keyArgs
Extra keyword arguments used to construct the task. The following arguments are automatically provided and cannot be overridden:
config
.parentTask
.
- name
Notes
The subtask must be defined by
Task.config.name
, an instance ofConfigurableField
orRegistryField
.
- prepareInputs(refList, coadd_bbox, psfMatchedWarpRefList=None)¶
Prepare the input warps for coaddition by measuring the weight for each warp.
Before coadding these Warps together compute the weight for each Warp.
- Parameters:
- Returns:
- prepareStats(mask=None)¶
Prepare the statistics for coadding images.
- Parameters:
- mask
int
, optional Bit mask value to exclude from coaddition.
- mask
- Returns:
- stats
Struct
Statistics as a struct with attributes:
statsCtrl
Statistics control object for coadd (
StatisticsControl
).statsFlags
Statistic for coadd (
Property
).
- stats
- processResults(coaddExposure, brightObjectMasks=None, dataId=None)¶
Interpolate over missing data and mask bright stars.
- run(skyInfo, *, warpRefList, imageScalerList, weightList, psfMatchedWarpRefList=None, altMaskList=None, mask=None, supplementaryData=None)¶
Assemble a coadd from input warps.
Assemble the coadd using the provided list of coaddTempExps. Since the full coadd covers a patch (a large area), the assembly is performed over small areas on the image at a time in order to conserve memory usage. Iterate over subregions within the outer bbox of the patch using
assembleSubregion
to stack the corresponding subregions from the coaddTempExps with the statistic specified. Set the edge bits the coadd mask based on the weight map.- Parameters:
- skyInfo
Struct
Struct with geometric information about the patch.
- warpRefList
list
List of dataset handles (data references) to Warps (previously called CoaddTempExps).
- imageScalerList
list
List of image scalers. Deprecated and will be removed after v29 in DM-49083.
- weightList
list
List of weights.
- psfMatchedWarpRefList
list
, optional List of dataset handles (data references) to psfMatchedWarps.
- altMaskList
list
, optional List of alternate masks to use rather than those stored with warp.
- mask
int
, optional Bit mask value to exclude from coaddition.
- supplementaryData
Struct
, optional Struct with additional data products needed to assemble coadd. Only used by subclasses that implement
_makeSupplementaryData
and overriderun
.
- skyInfo
- Returns:
- result
Struct
Results as a struct with attributes:
coaddExposure
Coadded exposure (
Exposure
).nImage
Exposure count image (
Image
), if requested.inputMap
Bit-wise map of inputs, if requested.
warpRefList
Input list of dataset handles (data refs) to the warps (
DeferredDatasetHandle
) (unmodified).imageScalerList
Input list of image scalers (
list
) (unmodified). Deprecated and will be removed after v29 in DM-49083.weightList
Input list of weights (
list
) (unmodified).
- result
- Raises:
- lsst.pipe.base.NoWorkFound
Raised if no dataset handles (data references) are provided.
- runQuantum(butlerQC, inputRefs, outputRefs)¶
Do butler IO and transform to provide in memory objects for tasks
run
method.- Parameters:
- butlerQC
QuantumContext
A butler which is specialized to operate in the context of a
lsst.daf.butler.Quantum
.- inputRefs
InputQuantizedConnection
Datastructure whose attribute names are the names that identify connections defined in corresponding
PipelineTaskConnections
class. The values of these attributes are thelsst.daf.butler.DatasetRef
objects associated with the defined input/prerequisite connections.- outputRefs
OutputQuantizedConnection
Datastructure whose attribute names are the names that identify connections defined in corresponding
PipelineTaskConnections
class. The values of these attributes are thelsst.daf.butler.DatasetRef
objects associated with the defined output connections.
- butlerQC
- setBrightObjectMasks(exposure, brightObjectMasks, dataId=None)¶
Set the bright object masks.
- Parameters:
- exposure
lsst.afw.image.Exposure
Exposure under consideration.
- brightObjectMasks
lsst.afw.table
Table of bright objects to mask.
- dataId
lsst.daf.butler.DataId
, optional Data identifier dict for patch.
- exposure
- setInexactPsf(mask)¶
Set INEXACT_PSF mask plane.
If any of the input images isn’t represented in the coadd (due to clipped pixels or chip gaps), the
CoaddPsf
will be inexact. Flag these pixels.- Parameters:
- mask
lsst.afw.image.Mask
Coadded exposure’s mask, modified in-place.
- mask