Hopefully you are using an extension to provide your templates. In this case you can add the following code to your_extension/Configuration/TCA/Overrides/sys_file_reference.php
$GLOBALS['TCA']['sys_file_reference']['columns']['crop']['config']['cropVariants'] = [
'demo' => [
'title' => 'Demo',
'allowedAspectRatios' => [
'4:3' => [
'title' => '4:3',
'value' => 4 / 3
],
],
'selectedRatio' => '4:3',
'cropArea' => [
'x' => 0.0,
'y' => 0.0,
'width' => 1.0,
'height' => 1.0,
],
'focusArea' => [
'x' => 1 / 3,
'y' => 1 / 3,
'width' => 1 / 3,
'height' => 1 / 3,
],
'coverAreas' => [
[
'x' => 0.05,
'y' => 0.85,
'width' => 0.9,
'height' => 0.1,
]
],
],
];
This will add the cropVariant demo
with:
- an aspect ratio of 4:3
- a focus area like you requested with 33% width and height, positioned in the middle of the image
- a cover area in the bottom of the image
Please note, that this will be applied to all sys_file_reference and not only to CTypes, so pages, news and so on will be also affected.