image_constrain_size_for_editor( int $width, int $height, string|int[] $size = 'medium', string $context = null ): int[]

Description

Compatibility

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

Parameters

$widthint

Width of the image in pixels.

$heightint

Height of the image in pixels.

$sizestring|int[]optional

Image size. Accepts any registered image size name, or an array of width and height values in pixels (in that order). Default 'medium'.Default: 'medium'

$contextstringoptional

Could be 'display' (like in a theme) or 'edit' (like inserting into an editor). Default null.Default: null

Return value

int[]

An array of width and height values.

• $0int

  The maximum width in pixels.

• $1int

  The maximum height in pixels.

Performance profile

How much work a call to image_constrain_size_for_editor() 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

Moderate

Reads stored settings via get_option(), cached per request but not free on a cold cache.

Scaling

Constant

No loop in the body: the same number of instructions runs whatever you pass in.

Instructions

34–70

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 128.

Plugin surface

1 hook

Third-party callbacks on 'editor_max_image_size' run inside this call, and their cost is not bounded by anything here.

Called by

3

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

What it touches

• optionoption read or writeget_option()called directly
• hookthird-party callbacksapply_filters()called directly
• cacheobject cachewp_cache_get()one call below image_constrain_size_for_editor()
• serializeserialisationmaybe_unserialize()one call below image_constrain_size_for_editor()

Further down the call graph this can also reach query 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 · 6 distinct outcomes

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

Hooks and filters fired · 1

One hook fires while image_constrain_size_for_editor() runs, in this order:

1. 1
   apply_filters( editor_max_image_size )filterline 138 (+73 into the body)

   Filters the maximum image size dimensions for the editor.

Uses · 5

• wp_get_additional_image_sizes()Retrieves additional image sizes.
• is_admin()Determines whether the current request is for an administrative interface page.
• get_option()Retrieves an option value based on an option name.
• apply_filters()Calls the callback functions that have been added to a filter hook.
• wp_constrain_dimensions()Calculates the new dimensions for a down-sampled image.

Used by · 3

• image_downsize()Scales an image to fit a particular size (such as 'thumb' or 'medium').
• image_get_intermediate_size()Retrieves the image's intermediate size (resized) path, width, and height.
• wp_prepare_attachment_for_js()Prepares an attachment post object for JS, where it is expected to be JSON-encoded and fit into an Attachment model.

Source code

View on Trac ↗View on GitHub ↗

65function image_constrain_size_for_editor( $width, $height, $size = 'medium', $context = null ) {66	global $content_width;67 68	$_wp_additional_image_sizes = wp_get_additional_image_sizes();69 70	if ( ! $context ) {71		$context = is_admin() ? 'edit' : 'display';72	}73 74	if ( is_array( $size ) ) {75		$max_width  = $size[0];76		$max_height = $size[1];77	} elseif ( 'thumb' === $size || 'thumbnail' === $size ) {78		$max_width  = (int) get_option( 'thumbnail_size_w' );79		$max_height = (int) get_option( 'thumbnail_size_h' );80		// Last chance thumbnail size defaults.81		if ( ! $max_width && ! $max_height ) {82			$max_width  = 128;83			$max_height = 96;84		}85	} elseif ( 'medium' === $size ) {86		$max_width  = (int) get_option( 'medium_size_w' );87		$max_height = (int) get_option( 'medium_size_h' );88 89	} elseif ( 'medium_large' === $size ) {90		$max_width  = (int) get_option( 'medium_large_size_w' );91		$max_height = (int) get_option( 'medium_large_size_h' );92 93		if ( (int) $content_width > 0 ) {94			$max_width = min( (int) $content_width, $max_width );95		}96	} elseif ( 'large' === $size ) {97		/*98		 * We're inserting a large size image into the editor. If it's a really99		 * big image we'll scale it down to fit reasonably within the editor100		 * itself, and within the theme's content width if it's known. The user101		 * can resize it in the editor if they wish.102		 */103		$max_width  = (int) get_option( 'large_size_w' );104		$max_height = (int) get_option( 'large_size_h' );105 106		if ( (int) $content_width > 0 ) {107			$max_width = min( (int) $content_width, $max_width );108		}109	} elseif ( ! empty( $_wp_additional_image_sizes ) && in_array( $size, array_keys( $_wp_additional_image_sizes ), true ) ) {110		$max_width  = (int) $_wp_additional_image_sizes[ $size ]['width'];111		$max_height = (int) $_wp_additional_image_sizes[ $size ]['height'];112		// Only in admin. Assume that theme authors know what they're doing.113		if ( (int) $content_width > 0 && 'edit' === $context ) {114			$max_width = min( (int) $content_width, $max_width );115		}116	} else { // $size === 'full' has no constraint.117		$max_width  = $width;118		$max_height = $height;119	}120 121	/**122	 * Filters the maximum image size dimensions for the editor.123	 *124	 * @since 2.5.0125	 *126	 * @param int[]        $max_image_size {127	 *     An array of width and height values.128	 *129	 *     @type int $0 The maximum width in pixels.130	 *     @type int $1 The maximum height in pixels.131	 * }132	 * @param string|int[] $size     Requested image size. Can be any registered image size name, or133	 *                               an array of width and height values in pixels (in that order).134	 * @param string       $context  The context the image is being resized for.135	 *                               Possible values are 'display' (like in a theme)136	 *                               or 'edit' (like inserting into an editor).137	 */138	list( $max_width, $max_height ) = apply_filters( 'editor_max_image_size', array( $max_width, $max_height ), $size, $context );139 140	return wp_constrain_dimensions( $width, $height, $max_width, $max_height );141}

Changelog

Introduced in 2.5.0. 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 6.8.8 tag, from src/wp-includes/media.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

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