WordPress Resize Thumbnail Image

<?php
//WordPress Resize Thumbnail Image
//aq_resizer.php
/**
 * Title         : Aqua Resizer
 * Description   : Resizes WordPress images on the fly
 * Version       : 1.1.7
 * Author        : Syamil MJ
 * Author URI    : http://aquagraphite.com
 * License       : WTFPL - http://sam.zoy.org/wtfpl/
 * Documentation : https://github.com/sy4mil/Aqua-Resizer/
 *
 * @param string  $url    - (required) must be uploaded using wp media uploader
 * @param int     $width  - (required)
 * @param int     $height - (optional)
 * @param bool    $crop   - (optional) default to soft crop
 * @param bool    $single - (optional) returns an array if false
 * @uses  wp_upload_dir()
 * @uses  image_resize_dimensions() | image_resize()
 * @uses  wp_get_image_editor()
 *
 * @return str|array


 // Set size for image
$image_size = array(
'width'  => 600,
'height' => 380
);

// Get img URL, resize & crop
$thumb   = get_post_thumbnail_id();
$img_url = wp_get_attachment_url( $thumb,'full');
$image   = aq_resize( $img_url, $image_size['width'], $image_size['height'], true );

Add in function.php
include('aq_resizer.php');
 */

function aq_resize( $url, $width = null, $height = null, $crop = null, $single = true, $upscale = false ) {

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

// Caipt'n, ready to hook.
if ( true === $upscale ) add_filter( 'image_resize_dimensions', 'aq_upscale', 10, 6 );

// Define upload path & dir.
$upload_info = wp_upload_dir();
$upload_dir = $upload_info['basedir'];
$upload_url = $upload_info['baseurl'];

$http_prefix = "http://";
$https_prefix = "https://";

/* if the $url scheme differs from $upload_url scheme, make them match
  if the schemes differe, images don't show up. */
if(!strncmp($url,$https_prefix,strlen($https_prefix))){ //if url begins with https:// make $upload_url begin with https:// as well
$upload_url = str_replace($http_prefix,$https_prefix,$upload_url);
}
elseif(!strncmp($url,$http_prefix,strlen($http_prefix))){ //if url begins with http:// make $upload_url begin with http:// as well
$upload_url = str_replace($https_prefix,$http_prefix,$upload_url);
}


// Check if $img_url is local.
if ( false === strpos( $url, $upload_url ) ) return $url;

// 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 ) or ! getimagesize( $img_path ) ) return $url;

// 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 );
$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 || ( true == $crop && false == $upscale && ( $dst_w < $width || $dst_h < $height ) ) ) {
// Can't resize, so return origin image url.
return $url;
}
// Else check if cache exists.
elseif ( file_exists( $destfilename ) && getimagesize( $destfilename ) ) {
$img_url = "{$upload_url}{$dst_rel_path}-{$suffix}.{$ext}";
}
// Else, we resize the image and return the new resized image url.
else {

// Note: This pre-3.5 fallback check will edited out in subsequent version.
if ( function_exists( 'wp_get_image_editor' ) ) {

$editor = wp_get_image_editor( $img_path );

if ( is_wp_error( $editor ) || is_wp_error( $editor->resize( $width, $height, $crop ) ) )
return $url;

$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;
} else {
return $url;
}

} else {

$resized_img_path = image_resize( $img_path, $width, $height, $crop ); // Fallback foo.
if ( ! is_wp_error( $resized_img_path ) ) {
$resized_rel_path = str_replace( $upload_dir, '', $resized_img_path );
$img_url = $upload_url . $resized_rel_path;
} else {
return $url;
}

}

}
}

// Okay, leave the ship.
if ( true === $upscale ) remove_filter( 'image_resize_dimensions', 'aq_upscale' );

// Return the output.
if ( $single ) {
// str return.
$image = $img_url;
} else {
// array return.
$image = array (
0 => $img_url,
1 => $dst_w,
2 => $dst_h
);
}

return $image;
}


function aq_upscale( $default, $orig_w, $orig_h, $dest_w, $dest_h, $crop ) {
if ( ! $crop ) return $url; // 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 );
}