def test_calculate_image_frequency_moments_1(self):
frequency = numpy.linspace(0.9e8, 1.1e8, 9)
cube = create_low_test_image_from_gleam(npixel=512,
cellsize=0.0001,
frequency=frequency,
flux_limit=1.0)
log.debug(
export_image_to_fits(cube,
fitsfile='%s/test_moments_1_cube.fits' %
(self.dir)))
original_cube = copy_image(cube)
moment_cube = calculate_image_frequency_moments(cube, nmoment=1)
log.debug(
export_image_to_fits(
moment_cube,
fitsfile='%s/test_moments_1_moment_cube.fits' % (self.dir)))
reconstructed_cube = calculate_image_from_frequency_moments(
cube, moment_cube)
log.debug(
export_image_to_fits(
reconstructed_cube,
fitsfile='%s/test_moments_1_reconstructed_cube.fits' %
(self.dir)))
error = numpy.std(reconstructed_cube.data - original_cube.data)
assert error < 0.2
def deconvolve_cube(dirty: Image,
psf: Image,
prefix='',
**kwargs) -> (Image, Image):
""" Clean using a variety of algorithms
The algorithms available are:
hogbom: Hogbom CLEAN See: Hogbom CLEAN A&A Suppl, 15, 417, (1974)
hogbom-complex: Complex Hogbom CLEAN of stokesIQUV image
msclean: MultiScale CLEAN See: Cornwell, T.J., Multiscale CLEAN (IEEE Journal of Selected Topics in Sig Proc,
2008 vol. 2 pp. 793-801)
mfsmsclean, msmfsclean, mmclean: MultiScale Multi-Frequency See: U. Rau and T. J. Cornwell,
“A multi-scale multi-frequency deconvolution algorithm for synthesis imaging in radio interferometry,” A&A 532,
A71 (2011).
For example::
comp, residual = deconvolve_cube(dirty, psf, niter=1000, gain=0.7, algorithm='msclean',
scales=[0, 3, 10, 30], threshold=0.01)
For the MFS clean, the psf must have number of channels >= 2 * nmoment
:param dirty: Image dirty image
:param psf: Image Point Spread Function
:param window_shape: Window image (Bool) - clean where True
:param mask: Window in the form of an image, overrides window_shape
:param algorithm: Cleaning algorithm: 'msclean'|'hogbom'|'mfsmsclean'
:param gain: loop gain (float) 0.7
:param threshold: Clean threshold (0.0)
:param fractional_threshold: Fractional threshold (0.01)
:param scales: Scales (in pixels) for multiscale ([0, 3, 10, 30])
:param nmoment: Number of frequency moments (default 3)
:param findpeak: Method of finding peak in mfsclean: 'Algorithm1'|'ASKAPSoft'|'CASA'|'RASCIL', Default is RASCIL.
:return: component image, residual image
See also
:py:func:`rascil.processing_components.arrays.cleaners.hogbom`
:py:func:`rascil.processing_components.arrays.cleaners.hogbom_complex`
:py:func:`rascil.processing_components.arrays.cleaners.msclean`
:py:func:`rascil.processing_components.arrays.cleaners.msmfsclean`
"""
assert isinstance(dirty, Image), dirty
assert image_is_canonical(dirty)
assert isinstance(psf, Image), psf
assert image_is_canonical(psf)
window_shape = get_parameter(kwargs, 'window_shape', None)
if window_shape == 'quarter':
log.info("deconvolve_cube %s: window is inner quarter" % prefix)
qx = dirty.shape[3] // 4
qy = dirty.shape[2] // 4
window = numpy.zeros_like(dirty.data)
window[..., (qy + 1):3 * qy, (qx + 1):3 * qx] = 1.0
log.info(
'deconvolve_cube %s: Cleaning inner quarter of each sky plane' %
prefix)
elif window_shape == 'no_edge':
edge = get_parameter(kwargs, 'window_edge', 16)
nx = dirty.shape[3]
ny = dirty.shape[2]
window = numpy.zeros_like(dirty.data)
window[..., (edge + 1):(ny - edge), (edge + 1):(nx - edge)] = 1.0
log.info(
'deconvolve_cube %s: Window omits %d-pixel edge of each sky plane'
% (prefix, edge))
elif window_shape is None:
log.info("deconvolve_cube %s: Cleaning entire image" % prefix)
window = None
else:
raise ValueError("Window shape %s is not recognized" % window_shape)
mask = get_parameter(kwargs, 'mask', None)
if isinstance(mask, Image):
if window is not None:
log.warning(
'deconvolve_cube %s: Overriding window_shape with mask image' %
(prefix))
window = mask.data
psf_support = get_parameter(kwargs, 'psf_support',
max(dirty.shape[2] // 2, dirty.shape[3] // 2))
if (psf_support <= psf.shape[2] // 2) and (
(psf_support <= psf.shape[3] // 2)):
centre = [psf.shape[2] // 2, psf.shape[3] // 2]
psf.data = psf.data[..., (centre[0] - psf_support):(centre[0] +
psf_support),
(centre[1] - psf_support):(centre[1] +
psf_support)]
log.info('deconvolve_cube %s: PSF support = +/- %d pixels' %
(prefix, psf_support))
log.info('deconvolve_cube %s: PSF shape %s' %
(prefix, str(psf.data.shape)))
algorithm = get_parameter(kwargs, 'algorithm', 'msclean')
if algorithm == 'msclean':
log.info(
"deconvolve_cube %s: Multi-scale clean of each polarisation and channel separately"
% prefix)
gain = get_parameter(kwargs, 'gain', 0.7)
assert 0.0 < gain < 2.0, "Loop gain must be between 0 and 2"
thresh = get_parameter(kwargs, 'threshold', 0.0)
assert thresh >= 0.0
niter = get_parameter(kwargs, 'niter', 100)
assert niter > 0
scales = get_parameter(kwargs, 'scales', [0, 3, 10, 30])
fracthresh = get_parameter(kwargs, 'fractional_threshold', 0.01)
assert 0.0 < fracthresh < 1.0
comp_array = numpy.zeros_like(dirty.data)
residual_array = numpy.zeros_like(dirty.data)
for channel in range(dirty.data.shape[0]):
for pol in range(dirty.data.shape[1]):
if psf.data[channel, pol, :, :].max():
log.info(
"deconvolve_cube %s: Processing pol %d, channel %d" %
(prefix, pol, channel))
if window is None:
comp_array[channel, pol, :, :], residual_array[channel, pol, :, :] = \
msclean(dirty.data[channel, pol, :, :], psf.data[channel, pol, :, :],
None, gain, thresh, niter, scales, fracthresh, prefix)
else:
comp_array[channel, pol, :, :], residual_array[channel, pol, :, :] = \
msclean(dirty.data[channel, pol, :, :], psf.data[channel, pol, :, :],
window[channel, pol, :, :], gain, thresh, niter, scales, fracthresh,
prefix)
else:
log.info(
"deconvolve_cube %s: Skipping pol %d, channel %d" %
(prefix, pol, channel))
comp_image = create_image_from_array(comp_array, dirty.wcs,
dirty.polarisation_frame)
residual_image = create_image_from_array(residual_array, dirty.wcs,
dirty.polarisation_frame)
elif algorithm == 'msmfsclean' or algorithm == 'mfsmsclean' or algorithm == 'mmclean':
findpeak = get_parameter(kwargs, "findpeak", 'RASCIL')
log.info(
"deconvolve_cube %s: Multi-scale multi-frequency clean of each polarisation separately"
% prefix)
nmoment = get_parameter(kwargs, "nmoment", 3)
assert nmoment >= 1, "Number of frequency moments must be greater than or equal to one"
nchan = dirty.shape[0]
assert nchan > 2 * (nmoment -
1), "Require nchan %d > 2 * (nmoment %d - 1)" % (
nchan, 2 * (nmoment - 1))
dirty_taylor = calculate_image_frequency_moments(dirty,
nmoment=nmoment)
if nmoment > 1:
psf_taylor = calculate_image_frequency_moments(psf,
nmoment=2 * nmoment)
else:
psf_taylor = calculate_image_frequency_moments(psf, nmoment=1)
psf_peak = numpy.max(psf_taylor.data)
dirty_taylor.data /= psf_peak
psf_taylor.data /= psf_peak
log.info("deconvolve_cube %s: Shape of Dirty moments image %s" %
(prefix, str(dirty_taylor.shape)))
log.info("deconvolve_cube %s: Shape of PSF moments image %s" %
(prefix, str(psf_taylor.shape)))
gain = get_parameter(kwargs, 'gain', 0.7)
assert 0.0 < gain < 2.0, "Loop gain must be between 0 and 2"
thresh = get_parameter(kwargs, 'threshold', 0.0)
assert thresh >= 0.0
niter = get_parameter(kwargs, 'niter', 100)
assert niter > 0
scales = get_parameter(kwargs, 'scales', [0, 3, 10, 30])
fracthresh = get_parameter(kwargs, 'fractional_threshold', 0.1)
assert 0.0 < fracthresh < 1.0
comp_array = numpy.zeros(dirty_taylor.data.shape)
residual_array = numpy.zeros(dirty_taylor.data.shape)
for pol in range(dirty_taylor.data.shape[1]):
# Always use the Stokes I PSF
if psf_taylor.data[0, 0, :, :].max():
log.info("deconvolve_cube %s: Processing pol %d" %
(prefix, pol))
if window is None:
comp_array[:, pol, :, :], residual_array[:, pol, :, :] = \
msmfsclean(dirty_taylor.data[:, pol, :, :], psf_taylor.data[:, 0, :, :],
None, gain, thresh, niter, scales, fracthresh, findpeak, prefix)
else:
log.info(
'deconvolve_cube %s: Clean window has %d valid pixels'
% (prefix, int(numpy.sum(window[0, pol]))))
comp_array[:, pol, :, :], residual_array[:, pol, :, :] = \
msmfsclean(dirty_taylor.data[:, pol, :, :], psf_taylor.data[:, 0, :, :],
window[0, pol, :, :], gain, thresh, niter, scales, fracthresh,
findpeak, prefix)
else:
log.info("deconvolve_cube %s: Skipping pol %d" % (prefix, pol))
comp_image = create_image_from_array(comp_array, dirty_taylor.wcs,
dirty.polarisation_frame)
residual_image = create_image_from_array(residual_array,
dirty_taylor.wcs,
dirty.polarisation_frame)
return_moments = get_parameter(kwargs, "return_moments", False)
if not return_moments:
log.info("deconvolve_cube %s: calculating spectral cubes" % prefix)
comp_image = calculate_image_from_frequency_moments(
dirty, comp_image)
residual_image = calculate_image_from_frequency_moments(
dirty, residual_image)
else:
log.info("deconvolve_cube %s: constructed moment cubes" % prefix)
elif algorithm == 'hogbom':
log.info(
"deconvolve_cube %s: Hogbom clean of each polarisation and channel separately"
% prefix)
gain = get_parameter(kwargs, 'gain', 0.1)
assert 0.0 < gain < 2.0, "Loop gain must be between 0 and 2"
thresh = get_parameter(kwargs, 'threshold', 0.0)
assert thresh >= 0.0
niter = get_parameter(kwargs, 'niter', 100)
assert niter > 0
fracthresh = get_parameter(kwargs, 'fractional_threshold', 0.1)
assert 0.0 < fracthresh < 1.0
comp_array = numpy.zeros(dirty.data.shape)
residual_array = numpy.zeros(dirty.data.shape)
for channel in range(dirty.data.shape[0]):
for pol in range(dirty.data.shape[1]):
if psf.data[channel, pol, :, :].max():
log.info(
"deconvolve_cube %s: Processing pol %d, channel %d" %
(prefix, pol, channel))
if window is None:
comp_array[channel, pol, :, :], residual_array[channel, pol, :, :] = \
hogbom(dirty.data[channel, pol, :, :], psf.data[channel, pol, :, :],
None, gain, thresh, niter, fracthresh, prefix)
else:
comp_array[channel, pol, :, :], residual_array[channel, pol, :, :] = \
hogbom(dirty.data[channel, pol, :, :], psf.data[channel, pol, :, :],
window[channel, pol, :, :], gain, thresh, niter, fracthresh, prefix)
else:
log.info(
"deconvolve_cube %s: Skipping pol %d, channel %d" %
(prefix, pol, channel))
comp_image = create_image_from_array(comp_array, dirty.wcs,
dirty.polarisation_frame)
residual_image = create_image_from_array(residual_array, dirty.wcs,
dirty.polarisation_frame)
elif algorithm == 'hogbom-complex':
log.info(
"deconvolve_cube_complex: Hogbom-complex clean of each polarisation and channel separately"
)
gain = get_parameter(kwargs, 'gain', 0.1)
assert 0.0 < gain < 2.0, "Loop gain must be between 0 and 2"
thresh = get_parameter(kwargs, 'threshold', 0.0)
assert thresh >= 0.0
niter = get_parameter(kwargs, 'niter', 100)
assert niter > 0
fracthresh = get_parameter(kwargs, 'fractional_threshold', 0.1)
assert 0.0 <= fracthresh < 1.0
comp_array = numpy.zeros(dirty.data.shape)
residual_array = numpy.zeros(dirty.data.shape)
for channel in range(dirty.data.shape[0]):
for pol in range(dirty.data.shape[1]):
if pol == 0 or pol == 3:
if psf.data[channel, pol, :, :].max():
log.info(
"deconvolve_cube_complex: Processing pol %d, channel %d"
% (pol, channel))
if window is None:
comp_array[channel, pol, :, :], residual_array[channel, pol, :, :] = \
hogbom(dirty.data[channel, pol, :, :], psf.data[channel, pol, :, :],
None, gain, thresh, niter, fracthresh)
else:
comp_array[channel, pol, :, :], residual_array[channel, pol, :, :] = \
hogbom(dirty.data[channel, pol, :, :], psf.data[channel, pol, :, :],
window[channel, pol, :, :], gain, thresh, niter, fracthresh)
else:
log.info(
"deconvolve_cube_complex: Skipping pol %d, channel %d"
% (pol, channel))
if pol == 1:
if psf.data[channel, 1:2, :, :].max():
log.info(
"deconvolve_cube_complex: Processing pol 1 and 2, channel %d"
% (channel))
if window is None:
comp_array[channel, 1, :, :], comp_array[
channel, 2, :, :], residual_array[
channel, 1, :, :], residual_array[
channel, 2, :, :] = hogbom_complex(
dirty.data[channel, 1, :, :],
dirty.data[channel, 2, :, :],
psf.data[channel, 1, :, :],
psf.data[channel, 2, :, :], None,
gain, thresh, niter, fracthresh)
else:
comp_array[channel, 1, :, :], comp_array[
channel, 2, :, :], residual_array[
channel, 1, :, :], residual_array[
channel, 2, :, :] = hogbom_complex(
dirty.data[channel, 1, :, :],
dirty.data[channel, 2, :, :],
psf.data[channel, 1, :, :],
psf.data[channel, 2, :, :],
window[channel, pol, :, :], gain,
thresh, niter, fracthresh)
else:
log.info(
"deconvolve_cube_complex: Skipping pol 1 and 2, channel %d"
% (channel))
if pol == 2:
continue
comp_image = create_image_from_array(
comp_array,
dirty.wcs,
polarisation_frame=PolarisationFrame('stokesIQUV'))
residual_image = create_image_from_array(
residual_array,
dirty.wcs,
polarisation_frame=PolarisationFrame('stokesIQUV'))
else:
raise ValueError('deconvolve_cube %s: Unknown algorithm %s' %
(prefix, algorithm))
return comp_image, residual_image