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filter is not described

wp_get_attachment_image_attributes filter-hook . WP 2.8.0

Filters the list of attachment image attributes.

Usage

add_filter( 'wp_get_attachment_image_attributes', 'filter_function_name_7013', 10, 3 );
function filter_function_name_7013( $attr, $attachment, $size ){
	// filter...

	return $attr;
}
$attr(array)
Attributes for the image markup.
$attachment(WP_Post)
Image attachment post.
$size(string/array)
Requested size. Image size or array of width and height values (in that order).
Default: 'thumbnail'

Where the hook is called

wp_get_attachment_image()
wp-includes/media.php 919
$attr = apply_filters( 'wp_get_attachment_image_attributes', $attr, $attachment, $size );

Where the hook is used (in WP core)

wp-includes/media.php 1468
add_filter( 'wp_get_attachment_image_attributes', '_wp_post_thumbnail_class_filter' );
wp-includes/media.php 1481
remove_filter( 'wp_get_attachment_image_attributes', '_wp_post_thumbnail_class_filter' );