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filter is not described

image_downsize filter-hook . WP 2.5.0

Filters whether to preempt the output of image_downsize().

Passing a truthy value to the filter will effectively short-circuit down-sizing the image, returning that value as output instead.

Usage

add_filter( 'image_downsize', 'filter_function_name_3283', 10, 3 );
function filter_function_name_3283( $downsize, $id, $size ){
	// filter...

	return $downsize;
}
$downsize(true/false)
Whether to short-circuit the image downsize.
Default: false
$id(int)
Attachment ID for image.
$size(array/string)
Size of image. Image size or array of width and height values (in that order).
Default: 'medium'

Where the hook is called

image_downsize()
wp_prepare_attachment_for_js()
wp-includes/media.php 201
if ( $out = apply_filters( 'image_downsize', false, $id, $size ) ) {
wp-includes/media.php 3193
if ( $downsize = apply_filters( 'image_downsize', false, $attachment->ID, $size ) ) {

Where the hook is used (in WP core)

Does not used.