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MakeNoise - add noise to an image


astmknoise [OPTION...] ASTRdata


MakeNoise is part of GNU Astronomy Utilities 0.14. MakeNoise will add noise to all the pixels in an input dataset. The noise parameters can be specified with the options below.

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

All options and their values:
$ astmknoise -P
Inputs/Outputs and options:
$ info astmknoise
Full section in manual/book:
$ info MakeNoise
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

MakeNoise options:

-b, --background=FLT
Fixed background magnitude for whole input.
-h, --hdu=STR/INT
Extension name or number of input data.
-i, --instrumental=FLT
Instrument noise level (in pixel value units).
-I, --ignorecase
Ignore case in matching/searching columns.
-s, --sigma=FLT
Total noise sigma, ignore other options.
-z, --zeropoint=FLT
Zeropoint magnitude of input.
-D, --dontdelete
Don't delete output if it exists.
-K, --keepinputdir
Keep input directory for automatic output.
-o, --output=STR
Output file name.
-T, --type=STR
Type of output: e.g., int16, float32, etc...
Operating modes:
-?, --help
give this help list
-B, --bgisbrightness
Background is brightness, not magnitude.
List all config files and variables read.
BibTeX citation for this program.
Read configuration file STR immediately.
-e, --envseed
Use GSL_RNG_SEED environment variable for seed
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:


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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 MakeNoise is maintained as a Texinfo manual. If the info and MakeNoise programs are properly installed at your site, the command
info MakeNoise

should give you access to the complete manual.

January 2021 GNU Astronomy Utilities 0.14