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ImageWarp - warp (transform) input image


astimgwarp [OPTION...] [matrix.txt] ASTRdata ...


ImageWarp is part of GNU Astronomy Utilities 0.2.33-8a3b. ImageWarp will warp/transform the input image using an input coordinate matrix. Currently it accepts any general projective mapping (which includes affine mappings as a subset).

For more information, please run any of the following commands. They will respectively show you the `Invoking ImageWarp' subsection, the complete `ImageWarp' section, or the full GNU Astronomy Utilities manual. In particular the first contains a very complete explanation of each option.

info astimgwarp
info ImageWarp
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

ImageWarp options:

Header keyword number to stop reading WCS.
Header keyword number to start reading WCS.
-h, --hdu=STR
Extension name or number of input data.
-m, --matrix=STR
Warp/Transform matrix elements.
Do not shift to correct for FITS positioning.
-b, --maxblankfrac=FLT
Maximum fraction of area covered by blank.
-d, --doubletype
Do not convert output to input image type.
-D, --dontdelete
Don't delete output if it exists.
-K, --keepinputdir
Do not remove input's dir info for output.
-n, --nowcscorrection
Do not correct input image WCS.
-o, --output=STR
Output file or directory name.
-z, --zerofornoinput
Set pixels with no input to zero not blank.
Modular warpings:
-a, --align
Align the image and celestial axes.
-e, --shear=FLT[,FLT]
Shear along the given axis(es).
-f, --flip=FLT[,FLT]
Flip along the given axis(es).
-p, --project=FLT[,FLT]
Project along the given axis(es).
-r, --rotate=FLT
Rotate by the given angle in degrees.
-s, --scale=FLT[,FLT]
Scale along the given axis(es).
-t, --translate=FLT[,FLT]
Translate along the given axis(es).
Operating modes:
-?, --help
give this help list
BibTeX citation for ImageWarp.
No log file for programs which make one.
-N, --numthreads=INT
Number of CPU threads to use.
Only read current directory configuration file.
Only run if the program version is this.
-P, --printparams
Print parameter values to be used and abort.
-q, --quiet
Only report errors, remain quiet about steps.
-S, --setdirconf
Set default values for this directory and abort.
give a short usage message
-U, --setusrconf
Set default values for this user and abort.
-V, --version
print program version

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

GNU Astronomy Utilities home page:


Written by Mohammad Akhlaghi


Report bugs to


Copyright © 2015-2016, 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.


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

should give you access to the complete manual.

October 2016 GNU Astronomy Utilities 0.2.33-8a3b