stsdas.toolbox.imgtools¶
Tasks for performing operations on images and masks.
Notes¶
For questions or comments please see our github page. We encourage and appreciate user feedback.
Most of these notebooks rely on basic knowledge of the Astropy FITS I/O module. If you are unfamiliar with this module please see the Astropy FITS I/O user documentation before using this documentation.
The various image tasks found in the stsdas.toolbox.imgtools package have been replaced in the Numpy and Astropy libraries.
Contents:
addmasks¶
Please review the Notes section above before running any examples in this notebook
Addmasks is used to combine several masks or bad pixel lists. We can do
this using the numpy
bitwise tasks:
bitwise_or,
bitwise_and,
and
invert,
along with a slew of other numpy bit
functions.
Below we show examples of bitwise_and
and bitwise_or
.
# Standard Imports
import numpy as np
a = np.array([1,4,10])
b = np.array([1,0,8])
# OR
print(np.bitwise_or(a,b))
# AND
print(np.bitwise_and(a,b))
[ 1 4 10]
[1 0 8]
iminsert¶
Please review the Notes section above before running any examples in this notebook
Iminsert is used to insert a small image into a larger image. This is
easy to do with the Numpy array indexing after you’ve read in your
images with Astropy.io.fits
. Below we’ll show a quick array example.
# Standard Imports
import numpy as np
# generate test arrays
my_array = np.random.rand(7,5)
ones = np.array(([1,1],[1,1]))
# replace middle 3x3 square with ones
my_array[2:4,2:4] = ones
# Print result
print(my_array)
[[ 0.06888833 0.15088263 0.00241 0.09282496 0.07325408]
[ 0.78665832 0.3402431 0.5265134 0.46253075 0.54305974]
[ 0.63473001 0.92986634 1. 1. 0.0904689 ]
[ 0.2887482 0.50178461 1. 1. 0.78550679]
[ 0.07945175 0.12885675 0.06588469 0.63534732 0.62024358]
[ 0.53344071 0.2852475 0.03736071 0.30043438 0.97523821]
[ 0.10331126 0.52996828 0.51318396 0.47988347 0.7098808 ]]
improject¶
Please review the Notes section above before running any examples in this notebook
Improject is used to sum or average an image along one axis. This can be
accomplised using the
numpy.average
or the
numpy.sum
functions and choosing which dimensions you wish to collapse. Below we
show an example using numpy.average
.
# Standard Imports
import numpy as np
# build random test array
my_array = np.random.rand(5,4,3)
# reduce third dimension down
new_array = np.average(my_array, axis=2)
print(new_array.shape)
print(new_array)
# reduce second dimension down
new_array_2 = np.average(my_array, axis=1)
print(new_array_2.shape)
print(new_array_2)
(5, 4)
[[ 0.60660306 0.55628564 0.79297796 0.73016308]
[ 0.48911929 0.36071454 0.6167648 0.4261005 ]
[ 0.47187441 0.21748297 0.92223167 0.64068855]
[ 0.14900289 0.70091688 0.51759779 0.29799824]
[ 0.85235487 0.79360714 0.60374945 0.40032384]]
(5, 3)
[[ 0.70389997 0.59038403 0.72023831]
[ 0.4937127 0.44684555 0.47896609]
[ 0.43435416 0.5368765 0.71797754]
[ 0.45942245 0.4114324 0.37828199]
[ 0.64567646 0.51639255 0.82545747]]
mkgauss¶
Please review the Notes section above before running any examples in this notebook
The mkgauss funtionality has been replicated in the Photutils package with photutils.datasets.make_random_gaussians_table and photutils.datasets.make_gaussian_sources_image.
pixlocate¶
Please review the Notes section above before running any examples in this notebook
Pixlocate is used to print positions matching a certain value condition.
This is replicated with the numpy.where
function. Please see the
documentation
for more details and examples.
rd2xy-xy2rd¶
Please review the Notes section above before running any examples in this notebook
Rd2xy and xy2rd are used to translate RA/Dec to the pixel coordinate and
vice-versa. This capability is well covered in the astropy.wcs
package. Please see the
documentation for more
details on usage.
Not Replacing¶
boxinterp - Fill areas with smoothed values from surrounding area. See images.imfit notebook.
countfiles - Count how many files are in the input file template. Deprecated.
gcombine - Combine a set of GEIS images into one image. Deprecated, for FITS see stsdas.toolbox.imgtools.mstools.mscombine
gcopy - Generic multi-group copy utility. GEIS, deprecated.
gstatistics - Compute and print image pixel statistics for all groups. GEIS, deprecated. For FITS see images.imutil.imstatistics
imcalc - Perform general arithmetic operations on images. See images.imtuil.imarith.
imfill - Set fill value in image according to a mask. See images.imutil.imreplace.
listarea - Print an area of an image. See numpy basics documentation.
moveheader - Combine the header and pixels from two images. GEIS, deprecated.
pickfile - Get the file name picked from the input file template. Deprecated.
pixedit - Screen editor for image pixels. See images.tv.imedit
rbinary - Create an image from a binary file. Deprecated.
stack - Stack images to form a new image with one more dimension. See images.imutil.imstack
xyztable - Interpolate table values, writing results to a table. See images.imfit.imsurfit and tables.ttools.tcopy-tdump
xyztoim - Interpolate table values, writing results to an image. See images.imfit.imsurfit, Astropy Tables documentation, and tables.ttools.tcopy-tdump.