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filter is not described

wp_constrain_dimensions filter-hook . WP 4.1.0

Filters dimensions to constrain down-sampled images to.

Usage

add_filter( 'wp_constrain_dimensions', 'filter_function_name_8792', 10, 5 );
function filter_function_name_8792( $dimensions, $current_width, $current_height, $max_width, $max_height ){
	// filter...

	return $dimensions;
}
$dimensions(array)
The image width and height.
$current_width(int)
The current width of the image.
$current_height(int)
The current height of the image.
$max_width(int)
The maximum width permitted.
$max_height(int)
The maximum height permitted.

Where the hook is called

wp_constrain_dimensions()
wp-includes/media.php 472
return apply_filters( 'wp_constrain_dimensions', array( $w, $h ), $current_width, $current_height, $max_width, $max_height );

Where the hook is used (in WP core)

Does not used.