function attachment_url_to_postid( $url ) {
	global $wpdb;

	$dir  = wp_get_upload_dir();
	$path = $url;

	$site_url   = parse_url( $dir['url'] );
	$image_path = parse_url( $path );
	$post_id = 0;

	if ( $attachment_id_pos = strpos( $url, '?attachment_id=' ) ) {
        // "plain" url (permalinks not enabled)
		$starting_pos = $attachment_id_pos + 15; // 15 = length of "?attachment_id="
		$post_id = substr( $url, $starting_pos );
	} elseif ( $attachment_id = url_to_postid( $url ) ) {
		// this is an attachment permalink
		$post_id = $attachment_id;
	} else {
		// compensate for sizes
        // reduce path to original filename
		$path_parts = explode( '-', $image_path['path'] );
		$filename = end( $path_parts );
		$found = preg_match('/^[\d]+x[\d]+(\.[0-9a-zA-Z]{3,4})/', $filename, $matches );
		if ( $found ) {
			// size found
			$meta_values[] = str_replace( '-' . $matches[0], $matches[1], $path );
			$meta_values[] = str_replace( '-' . $matches[0], '-scaled'. $matches[1], $path );
		} else {
            // no size found
			$meta_values[] = $path;
			$extension = '.'. pathinfo( $path, PATHINFO_EXTENSION );
			$meta_values[] = str_replace( $extension, '-scaled'. $extension, $path );
		}

		foreach( $meta_values as $key => $value ) {
			// Force the protocols to match if needed.
			if ( isset( $image_path['scheme'] ) && ( $image_path['scheme'] !== $site_url['scheme'] ) ) {
				$meta_values[ $key ] = str_replace( $image_path['scheme'], $site_url['scheme'], $meta_values[ $key ] );
			}
            // remove baseurl from path
			if ( 0 === strpos( $meta_values[ $key ], $dir['baseurl'] . '/' ) ) {
				$meta_values[ $key ] = substr( $meta_values[ $key ], strlen( $dir['baseurl'] . '/' ) );
			}
		}

		$sql = 'SELECT `post_id`, `meta_value` FROM '. $wpdb->postmeta .' WHERE meta_key = "_wp_attached_file" AND ( `meta_value` = %s';
		if( isset( $meta_values[1] ) ) {
            // handle "-scaled" images
			$sql .= ' OR `meta_value` = %s';
		}
		$sql .= ')';
		$sql = $wpdb->prepare( $sql, $meta_values );
		$results = $wpdb->get_results( $sql );

		if ( $results ) {
			// Use the first available result, but prefer a case-sensitive match, if exists.
			$post_id = reset( $results )->post_id;

			if ( count( $results ) > 1 ) {
				foreach ( $results as $result ) {
                    if( in_array( $result->meta_value, $meta_values) ) {
						$post_id = $result->post_id;
						break;
					}
				}
			}
		}

	}
	/**
	 * Filters an attachment ID found by URL.
	 *
	 * @since 4.2.0
	 *
	 * @param int|null $post_id The post_id (if any) found by the function.
	 * @param string   $url     The URL being looked up.
	 */
	return (int) apply_filters( 'attachment_url_to_postid', $post_id, $url );
}