def _createSkyWcsFromMetadata(self):
# We need to know which direction the chip is "flipped" in order to
# make a sensible WCS from the header metadata.
wcs = makeSkyWcs(self.metadata, strip=True)
dimensions = bboxFromMetadata(self.metadata).getDimensions()
center = Point2D(dimensions / 2.0)
return makeFlippedWcs(wcs, self.FLIP_LR, self.FLIP_TB, center)
def prepareWcsData(wcs, amp, isTrimmed=True):
"""Put Wcs from an Amp image into CCD coordinates
Parameters
----------
wcs : `lsst.afw.geom.SkyWcs`
The WCS object to start from.
amp : `lsst.afw.table.AmpInfoRecord`
Amp object to use
isTrimmed : `bool`
Is the image to which the WCS refers trimmed of non-imaging pixels?
Returns
-------
ampWcs : `lsst.afw.geom.SkyWcs`
The modified WCS.
"""
if not amp.getHasRawInfo():
raise RuntimeError("Cannot modify wcs without raw amp information")
if isTrimmed:
ampBox = amp.getRawDataBBox()
else:
ampBox = amp.getRawBBox()
ampCenter = lsst.geom.Point2D(ampBox.getDimensions() / 2.0)
wcs = afwGeom.makeFlippedWcs(wcs, amp.getRawFlipX(), amp.getRawFlipY(),
ampCenter)
# Shift WCS for trimming
if isTrimmed:
trim_shift = ampBox.getMin() - amp.getBBox().getMin()
wcs = wcs.copyAtShiftedPixelOrigin(
lsst.geom.Extent2D(-trim_shift.getX(), -trim_shift.getY()))
# Account for shift of amp data in larger ccd matrix
offset = amp.getRawXYOffset()
return wcs.copyAtShiftedPixelOrigin(lsst.geom.Extent2D(offset))
def checkMakeFlippedWcs(self, skyWcs, skyAtol=1e-7 * arcseconds):
"""Check makeFlippedWcs on the provided WCS
"""
# make an arbitrary bbox, but one that includes zero in one axis
# and does not include zero in the other axis
# the center of the bbox is used as the center of flipping
# and the corners of the bbox are the input positions that are tested
bbox = Box2D(Point2D(-100, 1000), Extent2D(2000, 1501))
# dict of (isRight, isTop): position
minPos = bbox.getMin()
maxPos = bbox.getMax()
center = bbox.getCenter()
cornerDict = {
(False, False): minPos,
(False, True): Point2D(minPos[0], maxPos[1]),
(True, False): Point2D(maxPos[0], minPos[1]),
(True, True): maxPos,
}
for flipLR, flipTB in itertools.product((False, True), (False, True)):
flippedWcs = makeFlippedWcs(wcs=skyWcs,
flipLR=flipLR,
flipTB=flipTB,
center=center)
# the center is unchanged
self.assertSpherePointsAlmostEqual(skyWcs.pixelToSky(center),
flippedWcs.pixelToSky(center),
maxSep=skyAtol)
for isR, isT in itertools.product((False, True), (False, True)):
origPos = cornerDict[(isR, isT)]
flippedPos = cornerDict[(isR ^ flipLR, isT ^ flipTB)]
self.assertSpherePointsAlmostEqual(
skyWcs.pixelToSky(origPos),
flippedWcs.pixelToSky(flippedPos),
maxSep=skyAtol)
def prepareWcsData(wcs, amp, isTrimmed=True):
"""Put Wcs from an Amp image into CCD coordinates
Parameters
----------
wcs : `lsst.afw.geom.SkyWcs`
The WCS object to start from.
amp : `lsst.afw.table.AmpInfoRecord`
Amp object to use
isTrimmed : `bool`
Is the image to which the WCS refers trimmed of non-imaging pixels?
Returns
-------
ampWcs : `lsst.afw.geom.SkyWcs`
The modified WCS.
"""
if not amp.getHasRawInfo():
raise RuntimeError("Cannot modify wcs without raw amp information")
if isTrimmed:
ampBox = amp.getRawDataBBox()
else:
ampBox = amp.getRawBBox()
ampCenter = lsst.geom.Point2D(ampBox.getDimensions()/2.0)
wcs = afwGeom.makeFlippedWcs(wcs, amp.getRawFlipX(), amp.getRawFlipY(), ampCenter)
# Shift WCS for trimming
if isTrimmed:
trim_shift = ampBox.getMin() - amp.getBBox().getMin()
wcs = wcs.copyAtShiftedPixelOrigin(lsst.geom.Extent2D(-trim_shift.getX(), -trim_shift.getY()))
# Account for shift of amp data in larger ccd matrix
offset = amp.getRawXYOffset()
return wcs.copyAtShiftedPixelOrigin(lsst.geom.Extent2D(offset))
def _flipChipsLR(exp, wcs, detectorId, dims=None):
"""Flip the chip left/right or top/bottom. Process either/and the pixels and wcs
Most chips are flipped L/R, but the rotated ones (100..103) are flipped T/B
"""
flipLR, flipTB = (False, True) if detectorId in (100, 101, 102, 103) else (True, False)
if exp:
exp.setMaskedImage(afwMath.flipImage(exp.getMaskedImage(), flipLR, flipTB))
if wcs:
ampDimensions = exp.getDimensions() if dims is None else dims
ampCenter = geom.Point2D(ampDimensions/2.0)
wcs = afwGeom.makeFlippedWcs(wcs, flipLR, flipTB, ampCenter)
return exp, wcs
def _flipChipsLR(exp, wcs, dataId, dims=None):
"""Flip the chip left/right or top/bottom. Process either/and the pixels and wcs
Most chips are flipped L/R, but the rotated ones (100..103) are flipped T/B
"""
flipLR, flipTB = (False, True) if dataId['ccd'] in (100, 101, 102, 103) else (True, False)
if exp:
exp.setMaskedImage(afwMath.flipImage(exp.getMaskedImage(), flipLR, flipTB))
if wcs:
ampDimensions = exp.getDimensions() if dims is None else dims
ampCenter = afwGeom.Point2D(ampDimensions/2.0)
wcs = afwGeom.makeFlippedWcs(wcs, flipLR, flipTB, ampCenter)
return exp, wcs
def makeWcs(self, metadata):
wcs = makeSkyWcs(metadata, strip=True)
dimensions = bboxFromMetadata(metadata).getDimensions()
center = Point2D(dimensions/2.0)
return makeFlippedWcs(wcs, self.FLIP_LR, self.FLIP_TB, center)
