Coverage for /wheeldirectory/casa-6.7.0-12-py3.10.el8/lib/py/lib/python3.10/site-packages/casatasks/specsmooth.py: 56%
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« prev ^ index » next coverage.py v7.6.4, created at 2024-10-31 17:39 +0000
1##################### generated by xml-casa (v2) from specsmooth.xml ################
2##################### 750dccf3562318cbdb15c36de3abf077 ##############################
3from __future__ import absolute_import
4import numpy
5from casatools.typecheck import CasaValidator as _val_ctor
6_pc = _val_ctor( )
7from casatools.coercetype import coerce as _coerce
8from casatools.errors import create_error_string
9from .private.task_specsmooth import specsmooth as _specsmooth_t
10from casatasks.private.task_logging import start_log as _start_log
11from casatasks.private.task_logging import end_log as _end_log
12from casatasks.private.task_logging import except_log as _except_log
14class _specsmooth:
15 """
16 specsmooth ---- Smooth an image region in one dimension
18 --------- parameter descriptions ---------------------------------------------
20 imagename Name of the input image
21 outfile Output image name.
22 box Rectangular region to select in direction plane. Default is to use the entire direction plane.
23 chans Channels to use. Channels must be contiguous. Default is to use all channels.
24 stokes Stokes planes to use. Planes specified must be contiguous. Default is to use all Stokes planes.
25 region Region selection. Default is to use the full image.
26 mask Mask to use. Default is none..
27 overwrite Overwrite the output if it exists?
28 stretch Stretch the mask if necessary and possible? Default False
29 axis The profile axis. Default: use the spectral axis if one exists, axis 0 otherwise (<0).
30 function Convolution function. hanning and boxcar are supported functions. Minimum match is supported.
31 width Width of boxcar, in pixels.
32 dmethod Decimation method. "" means no decimation, "copy" and "mean" are also supported (minimum match).
33 [1;42mRETURNS[1;m record
35 --------- examples -----------------------------------------------------------
39 Smooth an image region in one dimension.
41 ARAMETER SUMMARY
42 imagename Name of the input (CASA, FITS, MIRIAD) image
43 box Rectangular region to select in direction plane.
44 Default is to use the entire direction plane. Only a single box may be specified.
45 chans Channels to use. Channels must be contiguous.
46 Default is to use all channels.
47 stokes Stokes planes to use. Planes specified must be
48 contiguous. Default is to use all Stokes planes.
49 region Region selection. Default is to use the full image.
50 mask Mask to use. Default is none.
51 overwrite If the specified outfile already exists, overwrite it if True.
52 stretch Stretch the input mask if necessary and possible? Only used if a mask is specified.
54 axis Pixel axis along which to do the convolution <0 means use the spectral axis.
55 function Convolution function to use. Supported values are "boxcar" and "hanning". Minimum
56 match is supported.
57 width Width of boxcar in pixels. Used only if function parameter minimally matches "boxcar".
58 dmethod Plane decimation method. "" means no decimation should be performed. Other supported
59 values are "copy" and "mean". Minimal match is supported. See below for details.
61 This application performs one dimensional convolution along a specified axis of an image
62 or selected region of an image. Hanning smoothing and boxcar smoothing are supported.
63 Both float valued and complex valued images are supported. Masked pixel values are set to
64 zero prior to convolution. All nondefault pixel masks are ignored during
65 the calculation. The convolution is done in the image domain (i.e., not
66 with an FFT).
68 BOXCAR SMOOTHING
70 One dimensional boxcar convolution is defined by
72 z[i] = (y[i] + y[i+i] + ... + y[i+w])/w
74 where z[i] is the value at pixel i in the box car smoothed image, y[k]
75 is the pixel value of the input image at pixel k, and w is a postivie integer
76 representing the width of the boxcar in pixels. The length of the axis along which the
77 convolution is to occur must be at least w pixels in the selected region,
78 unless decimation using the mean function is chosen in which case the axis
79 length must be at least 2*w (see below).
81 If dmethod="" (no decimation), the length of the output axis will be equal
82 to the length of the input axis - w + 1. The pixel mask, ORed with the OTF mask
83 if specified, is copied from the selected region of the input image to the
84 output image. Thus for example, if the selected region in the input image has
85 six planes along the convolution axis, if the specified boxcar width is 2,
86 and if the pixel values, which are all unmasked, on a slice along this axis
87 are [1, 2, 5, 10, 17, 26], then the corresponding output slice will be of
88 length five pixels and the output pixel values will be [1.5, 3.5, 7.5, 13.5, 21.5].
90 If dmethod="copy", the output image is the image calculated
91 if dmethod="", except that only every wth plane is kept. Both the pixel and mask
92 values of these planes are copied directly to the output image, without further
93 processing. Thus for example, if the selected region in the input image has six
94 planes along the convolution axis, the boxcar width is chosen to be 2, and if
95 the pixel values, which are all unmasked, on a slice along this axis are [1, 2,
96 5, 10, 17, 26], the corresponding output pixel values will be [1.5, 7.5, 21.5].
98 If dmethod="mean", first the image described in the dmethod=""
99 case is calculated. Then, the ith plane of the output image is calculated by
100 averaging the i*w to the (i+1)*w-1 planes of this intermediate image. Thus, for
101 example, if the selected region in the input image has six planes along the
102 convolution axis, the boxcar width is chosen to be 2, and if the pixel values,
103 which are all unmasked, on a slice along this axis are [1, 2, 5, 10, 17, 26],
104 then the corresponding output pixel values will be [2.5, 10.5]. Any pixels at the
105 end of the convolution axis of the intermediate image that do not fall into a complete bin of
106 width w are ignored. Masked values are taken into consideration when forming this
107 average, so if one of the values is masked, it is not used in the average. If at
108 least one of the values in the intermediate image bin is not masked, the
109 corresponding output pixel will not be masked.
111 HANNING SMOOTHING
113 Hanning convolution of one axis of an image is defined by
115 z[i] = 0.25*y[i-1] + 0.5*y[i] + 0.25*y[i+1] (equation 1)
117 where z[i] is the value at pixel i in the hanning smoothed image, and
118 y[i-1], y[i], and y[i+1] are the values of the input image at pixels i-1,
119 i, and i+1 respectively. The length of the axis along which the convolution is
120 to occur must be at least three pixels in the selected region.
122 If dmethod="" (no decimation of image planes), the length of the output axis will
123 be the same as that of the input axis. The output pixel values along the convolution
124 axis will be related to those of the input values according to equation 1, except
125 the first and last pixels. In that case,
127 z[0] = 0.5*(y[0] + y[1])
129 and,
131 z[N-1] = 0.5*(y[N-2] + y[N-1])
133 where N is the number of pixels along the convolution aixs.
134 The pixel mask, ORed with the OTF mask if specified, is copied from the selected
135 region of the input image to the output image. Thus for example, if the selected
136 region in the input image has six planes along the convolution axis, and if the pixel
137 values, which are all unmasked, on a slice along this axis are [1, 2, 5, 10, 17, 26],
138 the corresponding output pixel values will be [1.5, 2.5, 5.5, 10.5, 17.5, 21.5].
140 If dmethod="copy", the output image is the image calculated if
141 dmethod="", except that only the odd-numbered planes are kept. Furthermore, if the
142 number of planes along the convolution axis in the selected region of the input image
143 is even, the last odd number plane is also discarded. Thus, if the selected region
144 has N pixels along the convolution axis in the input image, along the convolution
145 axis the output image will have (N-1)/2 planes if N is odd, or (N-2)/2 planes if N
146 is even. The pixel and mask values are copied directly, without further
147 processing. Thus for example, if the selected region in the input image has six planes
148 along the convolution axis, and if the pixel values, which are all unmasked, on a slice
149 along this axis are [1, 2, 5, 10, 17, 26], the corresponding output pixel values will be
150 [2.5, 10.5].
152 If dmethod="mean", first the image described in the dmethod="" case
153 is calculated. The first plane and last plane(s) of that image are then discarded as
154 described in the dmethod="copy" case. Then, the ith plane of the output
155 image is calculated by averaging the (2*i)th and (2*i + 1)th planes of the intermediate
156 image. Thus for example, if the selected region in the input image has six planes
157 along the convolution axis, and if the pixel values, which are all unmasked, on a slice
158 along this axis are [1, 2, 5, 10, 17, 26], the corresponding output pixel values will be
159 [4.0, 14.0]. Masked values are taken into consideration when forming this average, so if
160 one of the values is masked, it is not used in the average. If at least one of the values
161 in the input pair is not masked, the corresponding output pixel will not be masked.
164 EXAMPLES
166 # boxcar smooth the spectral axis by 3 pixels, say it's axis 2 and only
167 # write every other pixel
168 specsmooth(imagename="mynonsmoothed.im", outfile="myboxcarsmoothed.im",
169 axis=2, function="boxcar", dmethod="copy", width=3, overwrite=True)
171 # hanning smooth the spectral axis, say it's axis 2 and do not perform decimation
172 # of image planes
173 specsmooth(imagename="mynonsmoothed.im", outfile="myhanningsmoothed.im",
174 axis=2, dmethod=""," overwrite=True)
177 """
179 _info_group_ = """analysis"""
180 _info_desc_ = """Smooth an image region in one dimension"""
182 def __call__( self, imagename='', outfile='', box='', chans='', stokes='', region='', mask='', overwrite=False, stretch=False, axis=int(-1), function='hanning', width=int(2), dmethod='copy' ):
183 schema = {'imagename': {'type': 'cReqPath', 'coerce': _coerce.expand_path}, 'outfile': {'type': 'cStr', 'coerce': _coerce.to_str}, 'box': {'type': 'cStr', 'coerce': _coerce.to_str}, 'chans': {'type': 'cStr', 'coerce': _coerce.to_str}, 'stokes': {'type': 'cStr', 'coerce': _coerce.to_str}, 'region': {'type': 'cVariant', 'coerce': [_coerce.to_variant]}, 'mask': {'type': 'cStr', 'coerce': _coerce.to_str}, 'overwrite': {'type': 'cBool'}, 'stretch': {'type': 'cBool'}, 'axis': {'type': 'cInt'}, 'function': {'type': 'cStr', 'coerce': _coerce.to_str}, 'width': {'type': 'cInt'}, 'dmethod': {'type': 'cStr', 'coerce': _coerce.to_str}}
184 doc = {'imagename': imagename, 'outfile': outfile, 'box': box, 'chans': chans, 'stokes': stokes, 'region': region, 'mask': mask, 'overwrite': overwrite, 'stretch': stretch, 'axis': axis, 'function': function, 'width': width, 'dmethod': dmethod}
185 assert _pc.validate(doc,schema), create_error_string(_pc.errors)
186 _logging_state_ = _start_log( 'specsmooth', [ 'imagename=' + repr(_pc.document['imagename']), 'outfile=' + repr(_pc.document['outfile']), 'box=' + repr(_pc.document['box']), 'chans=' + repr(_pc.document['chans']), 'stokes=' + repr(_pc.document['stokes']), 'region=' + repr(_pc.document['region']), 'mask=' + repr(_pc.document['mask']), 'overwrite=' + repr(_pc.document['overwrite']), 'stretch=' + repr(_pc.document['stretch']), 'axis=' + repr(_pc.document['axis']), 'function=' + repr(_pc.document['function']), 'width=' + repr(_pc.document['width']), 'dmethod=' + repr(_pc.document['dmethod']) ] )
187 task_result = None
188 try:
189 task_result = _specsmooth_t( _pc.document['imagename'], _pc.document['outfile'], _pc.document['box'], _pc.document['chans'], _pc.document['stokes'], _pc.document['region'], _pc.document['mask'], _pc.document['overwrite'], _pc.document['stretch'], _pc.document['axis'], _pc.document['function'], _pc.document['width'], _pc.document['dmethod'] )
190 except Exception as exc:
191 _except_log('specsmooth', exc)
192 raise
193 finally:
194 task_result = _end_log( _logging_state_, 'specsmooth', task_result )
195 return task_result
197specsmooth = _specsmooth( )