custom image resize

image-resize.php

<?php

/**
* Resizes an image and returns the resized URL. Uses native WordPress functionality.
*
* The function supports GD Library and ImageMagick. WordPress will pick whichever is most appropriate.
* If none of the supported libraries are available, the function will return the original image url.
*
* Images are saved to the WordPress uploads directory, just like images uploaded through the Media Library.
* 
* Supports WordPress 3.5 and above.
*
*/

add_action('delete_attachment', 'cerchez_delete_resized_images');

function cerchez_image_resize($url, $width=null, $height=null, $crop=true, $align='c', $retina=false) {

	global $wpdb;
	$args = func_get_args();
	$common = cerchez_common_info($args);
	if (is_array($common)) {
		extract($common);
	} else {
		return $common;
	}

	if ( ! file_exists($dest_file_name)) {
		// We only want to resize Media Library images, so we can be sure they get deleted correctly when appropriate
		$query = $wpdb->prepare("SELECT * FROM $wpdb->posts WHERE guid='%s'", $url);
		$get_attachment = $wpdb->get_results($query);
		$editor = wp_get_image_editor($file_path);
		if (is_wp_error($editor)) {
			if (is_user_logged_in()) print_r($editor);
			return null;
		}

		if ($crop) {
			$src_x = $src_y = 0;
			$src_w = $orig_width;
			$src_h = $orig_height;
			$cmp_x = $orig_width / $dest_width;
			$cmp_y = $orig_height / $dest_height;
			if ($cmp_x > $cmp_y) {
				$src_w = round ($orig_width / $cmp_x * $cmp_y);
				$src_x = round (($orig_width - ($orig_width / $cmp_x * $cmp_y)) / 2);
			} else if ($cmp_y > $cmp_x) {
				$src_h = round ($orig_height / $cmp_y * $cmp_x);
				$src_y = round (($orig_height - ($orig_height / $cmp_y * $cmp_x)) / 2);
			}
			if ($align && $align != 'c') {
				if (strpos ($align, 't') !== false) {
					$src_y = 0;
				}
				if (strpos ($align, 'b') !== false) {
					$src_y = $orig_height - $src_h;
				}
				if (strpos ($align, 'l') !== false) {
					$src_x = 0;
				}
				if (strpos ($align, 'r') !== false) {
					$src_x = $orig_width - $src_w;
				}
			}
			$editor->crop($src_x, $src_y, $src_w, $src_h, $dest_width, $dest_height);
		} else {
			$editor->resize($dest_width, $dest_height);
		}

		$saved = $editor->save($dest_file_name);

		if (is_wp_error($saved)) {
			if (is_user_logged_in()) {
				print_r($saved);
				unlink($dest_file_name);
			}
			return null;
		}

		// Add the resized dimensions and alignment to original image metadata, so the images can be deleted when the original image is delete from the Media Library
		if ($get_attachment) {
			$metadata = wp_get_attachment_metadata($get_attachment[0]->ID);
			if (isset($metadata['image_meta'])) {
				$md = $saved['width'] . 'x' . $saved['height'];
				if ($crop) $md .= ($align) ? "_${align}" : "_c";
				$metadata['image_meta']['resized_images'][] = $md;
				wp_update_attachment_metadata($get_attachment[0]->ID, $metadata);
			}
		}
		$resized_url = str_replace(basename($url), basename($saved['path']), $url);
	} else {
		$resized_url = str_replace(basename($url), basename($dest_file_name), $url);
	}
	return $resized_url;
}

// Returns common information shared by processing functions
function cerchez_common_info($args) {
	list($url, $width, $height, $crop, $align, $retina) = $args;
	if (empty($url)) {
		return is_user_logged_in() ? "image_not_specified" : null;
	}

	// Return if nocrop is set on query string
	if (preg_match('/(\?|&)nocrop/', $url)) {
		return $url;
	}

	// Get the image file path
	$urlinfo = parse_url($url);
	$wp_upload_dir = wp_upload_dir();

	if (preg_match('/\/[0-9]{4}\/[0-9]{2}\/.+$/', $urlinfo['path'], $matches)) {
		$file_path = $wp_upload_dir['basedir'] . $matches[0];
	} else {
		$pathinfo = parse_url( $url );
		$uploads_dir = is_multisite() ? '/files/' : '/wp-content/';
		$file_path = ABSPATH . str_replace(dirname($_SERVER['SCRIPT_NAME']) . '/', '', strstr($pathinfo['path'], $uploads_dir));
		$file_path = preg_replace('/(\/\/)/', '/', $file_path);
	}

	if (!file_exists($file_path)) {
		return null;
	}

	$size = is_user_logged_in() ? getimagesize($file_path) : @getimagesize($file_path);
	if (!$size) {
		return is_user_logged_in() ? "getimagesize_error_common" : null;
	}

	list($orig_width, $orig_height, $orig_type) = $size;
	if ($width && !$height) {
		$height = floor ($orig_height * ($width / $orig_width));
	} else if ($height && !$width) {
		$width = floor ($orig_width * ($height / $orig_height));
	} else if (!$width && !$height) {
		return $url;
	}
	$retina = $retina ? ($retina === true ? 2 : $retina) : 1;
	$dest_width = $width * $retina;
	$dest_height = $height * $retina;
	$info = pathinfo($file_path);
	$dir = $info['dirname'];
	$ext = $info['extension'];
	$name = wp_basename($file_path, ".$ext");
	$suffix = "${dest_width}x${dest_height}";
	if ($crop) {
		$suffix .= ($align) ? "_${align}" : "_c";
	}
	$dest_file_name = "${dir}/${name}-${suffix}.${ext}";

	return array(
		'dir' => $dir,
		'name' => $name,
		'ext' => $ext,
		'suffix' => $suffix,
		'orig_width' => $orig_width,
		'orig_height' => $orig_height,
		'orig_type' => $orig_type,
		'dest_width' => $dest_width,
		'dest_height' => $dest_height,
		'file_path' => $file_path,
		'dest_file_name' => $dest_file_name,
	);
}

// Deletes the resized images when the original image is deleted from the WordPress Media Library
function cerchez_delete_resized_images($post_id) {
	$metadata = wp_get_attachment_metadata($post_id);
	if (!$metadata) return;
	if (!isset($metadata['file']) || !isset($metadata['image_meta']['resized_images'])) return;
	$wp_upload_dir = wp_upload_dir();
	$pathinfo = pathinfo($metadata['file']);
	$resized_images = $metadata['image_meta']['resized_images'];
	foreach ($resized_images as $dims) {
		$file = $wp_upload_dir['basedir'] . '/' . $pathinfo['dirname'] . '/' . $pathinfo['filename'] . '-' . $dims . '.' . $pathinfo['extension'];
		is_user_logged_in() ? unlink($file) : @unlink($file);
	}
}


function ricca_get_image_id( $local_url ) {
	global $wpdb;
	$attachment = $wpdb->get_col( $wpdb->prepare( "SELECT ID FROM $wpdb->posts WHERE guid=%s;", $local_url ) );
	if ( count( $attachment ) > 0 ) {
		return $attachment[0];
	} else {
		return false;
	}
}

function ricca_resize_image( $url, $width = 810, $height = 456 ) {

	// Validate inputs.
	if ( ! $url || ( ! $width && ! $height ) ) {
		return false;
	}

	$crop = true;
	add_filter( 'image_resize_dimensions', 'ricca_temporary_upscale', 10, 6 ); //100% safe - ignore theme check nag

	// Define upload path & dir.
	$upload_info = wp_upload_dir();
	$upload_dir  = $upload_info['basedir'];
	$upload_url  = $upload_info['baseurl'];
	if ( is_ssl() && 'http:' == substr( $upload_url, 0, 5 ) ) {
		$upload_url = 'https:' . substr( $upload_url, 5 );
	}
	if ( is_ssl() && 'http:' == substr( $url, 0, 5 ) ) {
		$url = 'https:' . substr( $url, 5 );
	}

	// Check if $img_url is remote.
	if ( false === strpos( $url, $upload_url ) ) {

		$file_array          = array();
		$extension_available = false;
		preg_match( '/[^\?]+\.(jpg|jpe|jpeg|gif|png)/i', $url, $matches );
		if ( 0 == count( $matches ) ) {
			$matches[0] = $url;
			$matches[1] = md5( $url );
		} else {
			$extension_available = true;
		}
		$file_array['name'] = basename( $matches[0] );

		// check if attachment already exists.
		$attachment_args  = array(
			'posts_per_page' => 1,
			'post_type'      => 'attachment',
			'post_mime_type' => 'image',
			'name'           => basename( $matches[0], '.' . $matches[1] ),
		);
		$attachment_check = new Wp_Query( $attachment_args );
		if ( $attachment_check->have_posts() ) {
			$url = wp_get_attachment_url( $attachment_check->post->ID );
		} else {
			// download remote image via WordPress functions.
			if ( ! function_exists( 'media_handle_sideload' ) ) {
				require_once( ABSPATH . 'wp-admin/includes/image.php' );
				require_once( ABSPATH . 'wp-admin/includes/file.php' );
				require_once( ABSPATH . 'wp-admin/includes/media.php' );
			}
			$tmp = download_url( $url );
			if ( is_wp_error( $tmp ) ) {
				return false;
			} else {
				if ( ! $extension_available ) {
					// get extension for an unknown remote image file
					$tmp_image_data = getimagesize( $tmp );
					if ( $tmp_image_data && isset( $tmp_image_data[2] ) ) {
						$extension    = image_type_to_extension( $tmp_image_data[2] );
						$new_tmp_file = str_replace( '.tmp', '', $tmp );
						if ( rename( $tmp, $new_tmp_file . $extension ) ) {
							$tmp = $new_tmp_file . $extension;
						}
						$file_array['type']  = image_type_to_mime_type( $tmp_image_data[2] );
						$file_array['error'] = 0;
						$file_array['size']  = filesize( $tmp );
					}
				}
				$file_array['tmp_name'] = $tmp;
				$attachment_id          = media_handle_sideload( $file_array, 0, basename( $matches[0], '.' . $matches[1] ) );
				if ( is_wp_error( $attachment_id ) ) {
					return false;
				} else {
					$url = wp_get_attachment_url( $attachment_id );
				}
			}
		}
	}

	// Define path of image.
	$rel_path = str_replace( $upload_url, '', $url );
	$img_path = $upload_dir . $rel_path;

	//check if img path exists, and is an image indeed
	if ( ! file_exists( $img_path ) || ! getimagesize( $img_path ) ) {
		return false;
	}

	// Get image info.
	$info                    = pathinfo( $img_path );
	$ext                     = $info['extension'];
	list( $orig_w, $orig_h ) = getimagesize( $img_path );

	// Get image size after cropping.
	$dims  = image_resize_dimensions( $orig_w, $orig_h, $width, $height, $crop ); //100% safe - ignore theme check nag
	$dst_w = $dims[4];
	$dst_h = $dims[5];

	// Return the original image only if it exactly fits the needed measures.
	if ( ! $dims && ( ( ( null === $height && $orig_w == $width ) xor ( null === $width && $orig_h == $height ) ) xor ( $height == $orig_h && $width == $orig_w ) ) ) {
		$img_url = $url;
		$dst_w   = $orig_w;
		$dst_h   = $orig_h;
	} else {
		// Use this to check if cropped image already exists, so we can return that instead.
		$suffix       = "{$dst_w}x{$dst_h}";
		$dst_rel_path = str_replace( '.' . $ext, '', $rel_path );
		$destfilename = "{$upload_dir}{$dst_rel_path}-{$suffix}.{$ext}";
		if ( ! $dims || ( $crop && ( $dst_w < $width || $dst_h < $height ) ) ) {
			// Can't resize, so return false saying that the action to do could not be processed as planned.
			return false;
		} elseif ( file_exists( $destfilename ) && getimagesize( $destfilename ) ) { // check if cache exists.
			$img_url = "{$upload_url}{$dst_rel_path}-{$suffix}.{$ext}";
		} else {
			if ( function_exists( 'wp_get_image_editor' ) ) { // we resize the image and return the new resized image url.
				$editor = wp_get_image_editor( $img_path );
				if ( is_wp_error( $editor ) || is_wp_error( $editor->resize( $width, $height, $crop ) ) ) {
					return false;
				}
				$editor->set_quality( 90 );
				$resized_file = $editor->save();
				if ( ! is_wp_error( $resized_file ) ) {
					$resized_rel_path = str_replace( $upload_dir, '', $resized_file['path'] );
					$img_url          = $upload_url . $resized_rel_path;

					// Add the resized dimensions to original image metadata (so we can delete our resized images when the original image is deleted from the Media Library).
					global $wpdb;
					$get_attachment = $wpdb->get_results( $wpdb->prepare( "SELECT * FROM $wpdb->posts WHERE guid=%s", $url ) );
					if ( ! $get_attachment ) {
						return $url;
					}
					$metadata = wp_get_attachment_metadata( $get_attachment[0]->ID );
					if ( isset( $metadata['sizes'] ) ) {
						$metadata['sizes'][ 'crop_' . $dst_w . '_' . $dst_h ] = array(
							'file'      => $resized_file['file'],
							'width'     => $resized_file['width'],
							'height'    => $resized_file['height'],
							'mime-type' => $resized_file['mime-type'],
						);
						wp_update_attachment_metadata( $get_attachment[0]->ID, $metadata );
					}
				} else {
					return false;
				}
			} else {
				return false;
			}
		}
	}

	// Return the output.
	$image = $img_url;

	// RETINA Support.
	$retina_w = $dst_w * 2;
	$retina_h = $dst_h * 2;

	//get image size after cropping
	$dims_x2  = image_resize_dimensions( $orig_w, $orig_h, $retina_w, $retina_h, $crop ); //100% safe - ignore theme check nag
	$dst_x2_w = $dims_x2[4];
	$dst_x2_h = $dims_x2[5];

	// If possible lets make the @2x image.
	if ( $dst_x2_h ) {
		// @2x image url.
		$destfilename = "{$upload_dir}{$dst_rel_path}-{$suffix}@2x.{$ext}";

		// check if retina image exists.
		if ( file_exists( $destfilename ) && getimagesize( $destfilename ) ) {
			// already exists, do nothing.
		} else {
			// doesnt exist, lets create it.
			$editor = wp_get_image_editor( $img_path );
			if ( ! is_wp_error( $editor ) ) {
				$editor->resize( $retina_w, $retina_h, $crop );
				$editor->set_quality( 80 );
				$filename     = $editor->generate_filename( $dst_w . 'x' . $dst_h . '@2x' );
				$resized_file = $editor->save( $filename );

				// Add the resized dimensions to original image metadata (so we can delete our resized retina images when the original image is delete from the Media Library)
				global $wpdb;
				$get_attachment = $wpdb->get_results( $wpdb->prepare( "SELECT * FROM $wpdb->posts WHERE guid=%s", $url ) );
				if ( ! $get_attachment ) {
					return $url;
				}
				$metadata = wp_get_attachment_metadata( $get_attachment[0]->ID );
				if ( isset( $metadata['sizes'] ) ) {
					$metadata['sizes'][ 'crop_' . $dst_w . '_' . $dst_h . '_@2x' ] = array(
						'file'      => $resized_file['file'],
						'width'     => $resized_file['width'],
						'height'    => $resized_file['height'],
						'mime-type' => $resized_file['mime-type'],
					);
					wp_update_attachment_metadata( $get_attachment[0]->ID, $metadata );
				}
			}
		}
	}

	remove_filter( 'image_resize_dimensions', 'ricca_temporary_upscale' ); //100% safe - ignore theme check nag

	return $image;
}

/**
 * Callback to overwrite WP computing of thumbnail measures temporary for private function.
 */
function ricca_temporary_upscale( $default, $orig_w, $orig_h, $dest_w, $dest_h, $crop ) {
	if ( ! $crop ) {
		return null; // Let the WordPress default function handle this.
	}

	// Here is the point we allow to use larger image size than the original one.
	$aspect_ratio = $orig_w / $orig_h;
	$new_w        = $dest_w;
	$new_h        = $dest_h;

	if ( ! $new_w ) {
			$new_w = intval( $new_h * $aspect_ratio );
	}

	if ( ! $new_h ) {
			$new_h = intval( $new_w / $aspect_ratio );
	}

	$size_ratio = max( $new_w / $orig_w, $new_h / $orig_h );
	$crop_w     = round( $new_w / $size_ratio );
	$crop_h     = round( $new_h / $size_ratio );
	$s_x        = floor( ( $orig_w - $crop_w ) / 2 );
	$s_y        = floor( ( $orig_h - $crop_h ) / 2 );

	return array( 0, 0, (int) $s_x, (int) $s_y, (int) $new_w, (int) $new_h, (int) $crop_w, (int) $crop_h );
}