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NAME

calc-image-resized-size - Given size of an image (in WxH, e.g. "2592x1944") and ImageMagick-like resize instruction (e.g. "1024p>"), calculate new resized image

VERSION

This document describes version 0.009 of calc-image-resized-size (from Perl distribution App-ImageMagickUtils), released on 2022-01-16.

SYNOPSIS

Usage:

% calc-image-resized-size [--format=name|--json] [--(no)naked-res] [--page-result[=program]|--view-result[=program]] -- <size> <resize>

OPTIONS

* marks required options.

Main options

--resize=s*

Resize instruction, follows ImageMagick format.

Resize instruction can be given in several formats:

    Syntax                     Meaning
    -------------------------- ----------------------------------------------------------------
    ""                         No resizing.

    SCALE"%"                   Height and width both scaled by specified percentage.
    SCALEX"%x"SCALEY"%"        Height and width individually scaled by specified percentages. (Only one % symbol needed.)

    WIDTH                      Width given, height automagically selected to preserve aspect ratio.
    WIDTH">"                   Shrink width if larger, height automagically selected to preserve aspect ratio.
    WIDTH"^"                   Enlarge width if smaller, height automagically selected to preserve aspect ratio.

    "x"HEIGHT                  Height given, width automagically selected to preserve aspect ratio.
    "x"HEIGHT">"               Shrink height if larger, width automagically selected to preserve aspect ratio.
    "x"HEIGHT"^"               Enlarge height if smaller, width automagically selected to preserve aspect ratio.

    WIDTH"x"HEIGHT             Maximum values of height and width given, aspect ratio preserved.
    WIDTH"x"HEIGHT"^"          Minimum values of height and width given, aspect ratio preserved.
    WIDTH"x"HEIGHT"!"          Width and height emphatically given, original aspect ratio ignored.
    WIDTH"x"HEIGHT">"          Shrinks an image with dimension(s) larger than the corresponding width and/or height argument(s).
    WIDTH"x"HEIGHT"<"          Shrinks an image with dimension(s) larger than the corresponding width and/or height argument(s).

    NUMBER"^>"                 Shrink shortest side if larger than number, aspect ratio preserved.
    NUMBER"^<"                 Enlarge shortest side if larger than number, aspect ratio preserved.
    "^"NUMBER">"               Shrink longer side if larger than number, aspect ratio preserved.
    "^"NUMBER"<"               Enlarge longer side if larger than number, aspect ratio preserved.

Currently unsupported:

    AREA"@"                    Resize image to have specified area in pixels. Aspect ratio is preserved.
    X":"Y                      Here x and y denotes an aspect ratio (e.g. 3:2 = 1.5).

Ref: <http://www.imagemagick.org/script/command-line-processing.php#geometry>

Can also be specified as the 2nd command-line argument.

--size=s*

Image/video size, in <width>x<height> format, e.g. 2592x1944.

Can also be specified as the 1st command-line argument.

Output options

--format=s

Choose output format, e.g. json, text.

Default value:

 undef
--json

Set output format to json.

--naked-res

When outputing as JSON, strip result envelope.

Default value:

 0

By default, when outputing as JSON, the full enveloped result is returned, e.g.:

    [200,"OK",[1,2,3],{"func.extra"=>4}]

The reason is so you can get the status (1st element), status message (2nd element) as well as result metadata/extra result (4th element) instead of just the result (3rd element). However, sometimes you want just the result, e.g. when you want to pipe the result for more post-processing. In this case you can use `--naked-res` so you just get:

    [1,2,3]
--page-result

Filter output through a pager.

--view-result

View output using a viewer.

Other options

--help, -h, -?

Display help message and exit.

--version, -v

Display program's version and exit.

COMPLETION

This script has shell tab completion capability with support for several shells.

bash

To activate bash completion for this script, put:

 complete -C calc-image-resized-size calc-image-resized-size

in your bash startup (e.g. ~/.bashrc). Your next shell session will then recognize tab completion for the command. Or, you can also directly execute the line above in your shell to activate immediately.

It is recommended, however, that you install modules using cpanm-shcompgen which can activate shell completion for scripts immediately.

tcsh

To activate tcsh completion for this script, put:

 complete calc-image-resized-size 'p/*/`calc-image-resized-size`/'

in your tcsh startup (e.g. ~/.tcshrc). Your next shell session will then recognize tab completion for the command. Or, you can also directly execute the line above in your shell to activate immediately.

It is also recommended to install shcompgen (see above).

other shells

For fish and zsh, install shcompgen as described above.

EXAMPLES

 % calc-image-resized-size 2592x1944 ''
 2592x1944

 % calc-image-resized-size 2592x1944 20%
 518x388

 % calc-image-resized-size 2592x1944 20%x40%
 518x777

 % calc-image-resized-size 2592x1944 20x40%
 518x777

 % calc-image-resized-size 2592x1944 1024
 1024x768

 % calc-image-resized-size 2592x1944 '1024>'
 1024x768

 % calc-image-resized-size 2592x1944 '10240>'
 2592x1944

 % calc-image-resized-size 2592x1944 1024^
 2592x1944

 % calc-image-resized-size 2592x1944 10240^
 10240x7680

 % calc-image-resized-size 2592x1944 x1024
 1365x1024

 % calc-image-resized-size 2592x1944 'x768>'
 1024x768

 % calc-image-resized-size 2592x1944 'x7680>'
 2592x1944

 % calc-image-resized-size 2592x1944 x768^
 2592x1944

 % calc-image-resized-size 2592x1944 x7680^
 10240x7680

 % calc-image-resized-size 2592x1944 20000x10000
 2592x1944

 % calc-image-resized-size 2592x1944 20000x1000
 1333x1000

 % calc-image-resized-size 2592x1944 100x200
 100x75

 % calc-image-resized-size 2592x1944 100x100
 100x75

 % calc-image-resized-size 2592x1944 10000x5000^
 10000x7500

 % calc-image-resized-size 2592x1944 5000x10000^
 13333x10000

 % calc-image-resized-size 2592x1944 100x100^
 2592x1944

 % calc-image-resized-size 2592x1944 100x100!
 100x100

 % calc-image-resized-size 2592x1944 '10000x5000>'
 2592x1944

 % calc-image-resized-size 2592x1944 '5000x10000>'
 2592x1944

 % calc-image-resized-size 2592x1944 '3000x1000>'
 2592x1944

 % calc-image-resized-size 2592x1944 '2000x1000>'
 1333x1000

 % calc-image-resized-size 2592x1944 '100x100>'
 100x75

 % calc-image-resized-size 2592x1944 '10000x5000<'
 10000x7500

 % calc-image-resized-size 2592x1944 '5000x10000<'
 13333x10000

 % calc-image-resized-size 2592x1944 '3000x1000<'
 2592x1944

 % calc-image-resized-size 2592x1944 '2000x1000<'
 2592x1944

 % calc-image-resized-size 2592x1944 '100x100<'
 2592x1944

 % calc-image-resized-size 2592x1944 '1024^>'
 1365x1024

 % calc-image-resized-size 2592x1944 '10240^>'
 2592x1944

 % calc-image-resized-size 2592x1944 '1024^<'
 2592x1944

 % calc-image-resized-size 2592x1944 '10240^<'
 13653x10240

 % calc-image-resized-size 2592x1944 '^1024>'
 1024x768

 % calc-image-resized-size 2592x1944 '^10240>'
 2592x1944

 % calc-image-resized-size 2592x1944 '^1024<'
 2592x1944

 % calc-image-resized-size 2592x1944 '^10240<'
 10240x7680

HOMEPAGE

Please visit the project's homepage at https://metacpan.org/release/App-ImageMagickUtils.

SOURCE

Source repository is at https://github.com/perlancar/perl-App-ImageMagickUtils.

SEE ALSO

imgsize.

AUTHOR

perlancar <perlancar@cpan.org>

CONTRIBUTING

To contribute, you can send patches by email/via RT, or send pull requests on GitHub.

Most of the time, you don't need to build the distribution yourself. You can simply modify the code, then test via:

 % prove -l

If you want to build the distribution (e.g. to try to install it locally on your system), you can install Dist::Zilla, Dist::Zilla::PluginBundle::Author::PERLANCAR, and sometimes one or two other Dist::Zilla plugin and/or Pod::Weaver::Plugin. Any additional steps required beyond that are considered a bug and can be reported to me.

COPYRIGHT AND LICENSE

This software is copyright (c) 2022, 2021, 2020 by perlancar <perlancar@cpan.org>.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

BUGS

Please report any bugs or feature requests on the bugtracker website https://rt.cpan.org/Public/Dist/Display.html?Name=App-ImageMagickUtils

When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature.