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CONVOLVE(1) User Commands CONVOLVE(1)


Convolve - convolve an image with a given kernel


astconvolve [OPTION...] ASTRdata


Convolve is part of GNU Astronomy Utilities 0.18. Convolve will convolve an input image with a given spatial kernel (image) in the spatial domain (no edge effects) or frequency domain. The latter suffers from edge effects, but can be much faster.

For more information, please run any of the following commands. In particular the second contains a very comprehensive explanation of Convolve's invocation: expected input(s), output(s), and a full description of all the options.

$ astconvolve -P
$ info astconvolve
$ info Convolve
$ info gnuastro

If you couldn't find your answer in the manual, you can get direct help from experienced Gnuastro users and developers. For more information, please run:

$ info help-gnuastro

Convolve options:

Column name or number if input is a table.
Extension name or number of input data.
Deconvolution: min spectrum of sharp img.
Column name or number if kernel is a table.
File name of kernel for convolution.
Do not flip the kernel image.
Do not normalize the kernel image.
Select column(s): 'name', 'unit', 'comment'.
Micro-seconds to wait for standard input.
HDU containing the kernel.
Tessellation (tile grid):
Tile IDs in an image, the size of input.
Fraction of remainder to split last tile.
Interpolation metric (radial, manhattan).

-M, --numchannels=INT[,..] No. of channels in dim.s (FITS order).

Display 1 element/tile, not full input res.
Work (not tile) over channel edges.
Regular tile size on dim.s (FITS order).
View the steps in the frequency domain.
Don't delete output if it exists.
Keep input directory for automatic output.
Do not correct the edges in the spatial domain
Output file name.
Table fmt: 'fits-ascii', 'fits-binary', 'txt'.
Type of output: e.g., int16, float32, etc...
WCS linear matrix of output ('pc' or 'cd').
Operating modes:
-?, --help
give this help list
List all config files and variables read.
BibTeX citation for this program.
Read configuration file STR immediately.
Convolution domain: 'spatial', 'frequency'.
Do not parse any more configuration files.
Min. bytes to avoid RAM automatically.
Make 2*INT kernel to create input image.
Number of CPU threads to use.
Only run if the program version is STR.
Print parameter values to be used and abort.
Don't print mmap'd file's name and size.
Only report errors, remain quiet about steps.
Set default values for this directory and abort.
give a short usage message
Set default values for this user and abort.
print program version

Mandatory or optional arguments to long options are also mandatory or optional for any corresponding short options.

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Copyright © 2015-2022 Free Software Foundation, Inc. License GPLv3+: GNU General public license version 3 or later.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.

Written/developed by Mohammad Akhlaghi


The full documentation for Convolve is maintained as a Texinfo manual. If the info and Convolve programs are properly installed at your site, the command

info Convolve

should give you access to the complete manual.

July 2022 GNU Astronomy Utilities 0.18