wppaste
WordPress

_wp_make_subsizes( array $new_sizes, string $file, array $image_meta, int $attachment_id ): array

Since
5.3.0
Source
wp-admin/includes/image.php:430
Low-level function to create image sub-sizes.

Description

Updates the image meta after each sub-size is created.
Errors are stored in the returned image metadata array.

Compatibility

WordPress
since 5.3.0
PHP
7.4–8.6-dev
  • 6.7.7
  • 6.8.8
  • 6.9.7
  • 7.0.4
  • 7.1.0

Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.

Parameters

$new_sizesarray
Array defining what sizes to create.
$filestring
Full path to the image file.
$image_metaarray
The attachment meta data array.
$attachment_idint
Attachment ID to process.

Return value

array
The attachment meta data with updated sizes array. Includes an array of errors encountered while resizing.

Performance profile

How much work a call to _wp_make_subsizes() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.

Cost class
Heavy

Reaches the database via get_post().

Scaling
Scales with input

The body loops, so the work grows with what you pass in.

Instructions
7–67

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 98.

Plugin surface
None

Nothing here hands control to plugin code.

Called by
3

3 places in core call this, so the cost is paid more often than your own code shows.

What it touches

  • hookthird-party callbacksdo_action()one call below _wp_make_subsizes()
  • querycontent queryget_post()one call below _wp_make_subsizes()

Further down the call graph this can also reach cache, serialize, option and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.

What one call costs · 8 distinct outcomes

One number would be a lie: the work depends on which branch runs. These are every distinct cost _wp_make_subsizes() can have, taken from its control-flow graph on PHP 8.5.

WhenInstructionsCalls it makes
always7–21none
!empty($image_meta) && is_array($image_meta) && !empty($new_sizes) && is_wp_error()31–37array_merge(), array_filter(), wp_get_image_editor(), is_wp_error()
is_array($image_meta) && !empty($new_sizes) && !is_wp_error() && method_exists()40–47array_merge(), array_filter(), wp_get_image_editor(), is_wp_error(), method_exists()
is_array($image_meta) && !empty($new_sizes) && !is_wp_error() && !method_exists() && empty($created_sizes)44–50array_merge(), array_filter(), wp_get_image_editor(), is_wp_error(), method_exists(), ->multi_resize()
!empty($image_meta) && is_array($image_meta) && !empty($new_sizes) && !is_wp_error() && method_exists()46–53array_merge(), array_filter(), wp_get_image_editor(), is_wp_error(), ->maybe_exif_rotate(), is_wp_error(), method_exists()
!empty($image_meta) && is_array($image_meta) && !empty($new_sizes) && !is_wp_error() && !method_exists() && empty($created_sizes)50–56array_merge(), array_filter(), wp_get_image_editor(), is_wp_error(), ->maybe_exif_rotate(), is_wp_error(), method_exists(), ->multi_resize()
is_array($image_meta) && !empty($new_sizes) && !is_wp_error() && !method_exists() && !empty($created_sizes)55–61array_merge(), array_filter(), wp_get_image_editor(), is_wp_error(), method_exists(), ->multi_resize(), array_merge(), wp_update_attachment_metadata()
!empty($image_meta) && is_array($image_meta) && !empty($new_sizes) && !is_wp_error() && !method_exists() && !empty($created_sizes)61–67array_merge(), array_filter(), wp_get_image_editor(), is_wp_error(), ->maybe_exif_rotate(), is_wp_error(), method_exists(), ->multi_resize(), array_merge(), wp_update_attachment_metadata()

Across PHP versions

Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 98 instructions, 7–67 executed per call, 15 branches. The work does not change between versions.

An instruction is not a fixed amount of time, so a matching count is not necessarily the same speed; what it rules out is a difference in the work itself.

Uses · 3

Used by · 3

Source code

function _wp_make_subsizes( $new_sizes, $file, $image_meta, $attachment_id ) {	if ( empty( $image_meta ) || ! is_array( $image_meta ) ) {		// Not an image attachment.		return array();	} 	// Check if any of the new sizes already exist.	if ( isset( $image_meta['sizes'] ) && is_array( $image_meta['sizes'] ) ) {		foreach ( $image_meta['sizes'] as $size_name => $size_meta ) {			/*			 * Only checks "size name" so we don't override existing images even if the dimensions			 * don't match the currently defined size with the same name.			 * To change the behavior, unset changed/mismatched sizes in the `sizes` array in image meta.			 */			if ( array_key_exists( $size_name, $new_sizes ) ) {				unset( $new_sizes[ $size_name ] );			}		}	} else {		$image_meta['sizes'] = array();	} 	if ( empty( $new_sizes ) ) {		// Nothing to do...		return $image_meta;	} 	/*	 * Sort the image sub-sizes in order of priority when creating them.	 * This ensures there is an appropriate sub-size the user can access immediately	 * even when there was an error and not all sub-sizes were created.	 */	$priority = array(		'medium'       => null,		'large'        => null,		'thumbnail'    => null,		'medium_large' => null,	); 	$new_sizes = array_filter( array_merge( $priority, $new_sizes ) ); 	$editor = wp_get_image_editor( $file ); 	if ( is_wp_error( $editor ) ) {		// The image cannot be edited.		return $image_meta;	} 	// If stored EXIF data exists, rotate the source image before creating sub-sizes.	if ( ! empty( $image_meta['image_meta'] ) ) {		$rotated = $editor->maybe_exif_rotate(); 		if ( is_wp_error( $rotated ) ) {			// TODO: Log errors.		}	} 	if ( method_exists( $editor, 'make_subsize' ) ) {		foreach ( $new_sizes as $new_size_name => $new_size_data ) {			$new_size_meta = $editor->make_subsize( $new_size_data ); 			if ( is_wp_error( $new_size_meta ) ) {				// TODO: Log errors.			} else {				// Save the size meta value.				$image_meta['sizes'][ $new_size_name ] = $new_size_meta;				wp_update_attachment_metadata( $attachment_id, $image_meta );			}		}	} else {		// Fall back to `$editor->multi_resize()`.		$created_sizes = $editor->multi_resize( $new_sizes ); 		if ( ! empty( $created_sizes ) ) {			$image_meta['sizes'] = array_merge( $image_meta['sizes'], $created_sizes );			wp_update_attachment_metadata( $attachment_id, $image_meta );		}	} 	return $image_meta;

Changelog

Introduced in 5.3.0. Unchanged from 6.7.7 through 7.1.0.

  1. 6.7.7
  2. 6.8.8
  3. 6.9.7
  4. 7.0.4
  5. 7.1.0

Signature, return type and hooks compared across 5 parsed releases.

About this page

Parsed data
Generated from the wordpress-develop 7.0.4 tag, from src/wp-admin/includes/image.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.
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