wp_get_attachment_metadata() │ WP 2.1.0

Retrieves the metadata for an attached file (attachment).

Uses: get_post_meta()

Used By: wp_maybe_generate_attachment_metadata(), wp_get_original_image_path(), image_get_intermediate_size()

1 time — 0.000745 sec (slow) | 50000 times — 1.22 sec (fast) | PHP 7.0.8, WP 4.6

Hooks from the function

wp_get_attachment_metadata

Returns

array|false. Array of metadata for the specified attached file. If the data could not be retrieved, false will be returned.

Usage

$meta = wp_get_attachment_metadata( $attachment_id, $unfiltered );

$attachment_id(int) (required): The attachment ID whose metadata should be retrieved.
$unfiltered(boolean): If set to true, filters will be disabled.
Default: false

Examples

#1 Get the metadata of attachment 656 (picture):

$array = wp_get_attachment_metadata( 656 );

As a result, the variable $array will contain approximately the following data (depending on the attachment type):

[
	[width] => 356
	[height] => 299
	[file] => 2011/05/dinamic-archives.png
	[sizes] => [
			[thumbnail] => [
					[file] => dinamic-archives-80x80.png
					[width] => 80
					[height] => 80
					[mime-type] => image/png
				]

			[medium] => [
					[file] => dinamic-archives-120x100.png
					[width] => 120
					[height] => 100
					[mime-type] => image/png
				]

		]

	[image_meta] => [
			[aperture] => 0
			[credit] =>
			[camera] =>
			[caption] =>
			[created_timestamp] => 0
			[copyright] =>
			[focal_length] => 0
			[iso] => 0
			[shutter_speed] => 0
			[title] =>
		]

]

Let's bring up the sizes of the image:

$meta = wp_get_attachment_metadata( 656 );

if( $meta ){
	echo $meta['width'] .'x'. $meta['height']; //> 356х299
}

#2 Get the metadata of attachment 95 (video):

$array = wp_get_attachment_metadata( 95 );

As a result, the variable $array will contain approximately the following data (depending on the attachment type):

Array
(
	[filesize] => 61429114
	[mime_type] => video/mp4
	[length] => 1375
	[length_formatted] => 22:55
	[width] => 1280
	[height] => 720
	[fileformat] => mp4
	[dataformat] => quicktime
	[audio] => Array
		(
			[dataformat] => mp4
			[codec] => ISO/IEC 14496-3 AAC
			[sample_rate] => 44100
			[channels] => 2
			[bits_per_sample] => 16
			[lossless] =>
			[channelmode] => stereo
		)

	[created_timestamp] => 1538981268
)

#3 Get full URL to uploaded image file

NOTE that when calling wp_get_attachment_metadata(), the ARRAY index returned from file is the file path relative to wp-content/uploads.

If you want to get url of domain to link up, you can use snippet below

$attachment_metadata = wp_get_attachment_metadata( $attachment_id );

$upload_url = wp_upload_dir()['url'];
$file_rel_path = $attachment_metadata['sizes']['medium_large']['file'];

echo "{$upload_url}/{$file_rel_path}";

Changelog

Since 2.1.0	Introduced.
Since 6.0.0	The `$filesize` value was added to the returned array.
Since 7.1.0	`false` is now returned if the metadata is not an array, and when the result is filtered the `sizes` key is always an array when present.

`wp_get_attachment_metadata() wp get attachment metadata` code ^{WP 7.1}

wp-includes/post.php

function wp_get_attachment_metadata( $attachment_id = 0, $unfiltered = false ) {
	$attachment_id = (int) $attachment_id;

	if ( ! $attachment_id ) {
		$post = get_post();

		if ( ! $post ) {
			return false;
		}

		$attachment_id = $post->ID;
	}

	$data = get_post_meta( $attachment_id, '_wp_attachment_metadata', true );

	if ( ! is_array( $data ) || ! $data ) {
		return false;
	}

	if ( $unfiltered ) {
		return $data;
	}

	/**
	 * Filters the attachment meta data.
	 *
	 * @since 2.1.0
	 *
	 * @param array $data          Array of meta data for the given attachment.
	 * @param int   $attachment_id Attachment post ID.
	 */
	$data = apply_filters( 'wp_get_attachment_metadata', $data, $attachment_id );

	if ( ! is_array( $data ) ) {
		return false;
	}

	if ( array_key_exists( 'sizes', $data ) && ! is_array( $data['sizes'] ) ) {
		$data['sizes'] = array();
	}

	return $data;
}