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ConvertType - convert known data types to each other


astconvertt [OPTION...] InputFile1 [InputFile2] ... [InputFile4]


ConvertType is part of GNU Astronomy Utilities 0.14. ConvertType will convert any of the known input formats to any other of the known formats. The output file will have the same number of pixels.

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

All options and their values:
$ astconvertt -P
Inputs/Outputs and options:
$ info astconvertt
Full section in manual/book:
$ info ConvertType
Full Gnuastro manual/book:
$ 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

ConvertType options:

-h, --hdu=STR/INT
FITS input HDU, multiple calls possible.
Micro-seconds to wait for standard input.
-b, --borderwidth=INT
EPS/PDF border width in units of 1/72 inch.
Color map when only a single channel is given.
-D, --dontdelete
Don't delete output if it exists.
-K, --keepinputdir
Keep input directory for automatic output.
-o, --output=STR
Output filename or suffix.
Convert RGB input into HSV (in FITS output)
-u, --quality=INT
Quality of output JPEG image (1 to 100).
-w, --widthincm=FLT
Width in units of centimeters.
-x, --hex
Hexadecimal encoding in EPS. Default: ASCII85.
-A, --forcemin
Force --fluxmin, even when smaller than minimum.
-B, --forcemax
Force --fluxmax, even when larger than maximum.
-c, --change=STR
Change pixel values 'from_1:to_1,from_2:to_2'.
-C, --changeaftertrunc
First truncate then change pixel values.
-H, --fluxhigh=FLT
Higher flux truncation value.
-i, --invert
Invert the values in JPEG and EPS/PDF.
-L, --fluxlow=FLT
Lower flux truncation value.
-m, --maxbyte=INT
Maximum byte value for all color channels.
Operating modes:
-?, --help
give this help list
List all config files and variables read.
BibTeX citation for this program.
Read configuration file STR immediately.
Do not parse any more configuration files.
Information about output(s) in a log file.
Minimum bytes in array to not use ram RAM.
-N, --numthreads=INT
Number of CPU threads to use.
Only run if the program version is STR.
-P, --printparams
Print parameter values to be used and abort.
Don't print mmap'd file's name and size.
-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:


Report bugs to


Copyright © 2015-2021, 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 ConvertType is maintained as a Texinfo manual. If the info and ConvertType programs are properly installed at your site, the command
info ConvertType

should give you access to the complete manual.

January 2021 GNU Astronomy Utilities 0.14