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filter is not described

intermediate_image_sizes filter-hook . WP 2.5.0

Filters the list of intermediate image sizes.

Usage

add_filter( 'intermediate_image_sizes', 'filter_function_name_6769' );
function filter_function_name_6769( $image_sizes ){
	// filter...

	return $image_sizes;
}
$image_sizes(array)
An array of intermediate image sizes.
Default: are 'thumbnail', 'medium', 'medium_large', 'large'

Where the hook is called

get_intermediate_image_sizes()
wp-includes/media.php 801
return apply_filters( 'intermediate_image_sizes', $image_sizes );

Where the hook is used (in WP core)

wp-admin/includes/class-wp-site-icon.php 227
add_filter( 'intermediate_image_sizes', array( $this, 'intermediate_image_sizes' ) );