image_resize_dimensions( int $orig_w, int $orig_h, int $dest_w, int $dest_h, bool|array $crop = false )
Retrieves calculated resize dimensions for use in WP_Image_Editor.
Description
Calculates dimensions and coordinates for a resized image that fits within a specified width and height.
Cropping behavior is dependent on the value of $crop:
- If false (default), images will not be cropped.
- If an array in the form of array( x_crop_position, y_crop_position ):
- x_crop_position accepts ‘left’ ‘center’, or ‘right’.
- y_crop_position accepts ‘top’, ‘center’, or ‘bottom’. Images will be cropped to the specified dimensions within the defined crop area.
- If true, images will be cropped to the specified dimensions using center positions.
Parameters
- $orig_w
-
(Required) Original width in pixels.
- $orig_h
-
(Required) Original height in pixels.
- $dest_w
-
(Required) New width in pixels.
- $dest_h
-
(Required) New height in pixels.
- $crop
-
(Optional) Whether to crop image to specified width and height or resize. An array can specify positioning of the crop area.
Default value: false
Return
(false|array) False on failure. Returned array matches parameters for imagecopyresampled()
.
Source
File: wp-includes/media.php
function image_resize_dimensions( $orig_w, $orig_h, $dest_w, $dest_h, $crop = false ) {
if ($orig_w <= 0 || $orig_h <= 0)
return false;
// at least one of dest_w or dest_h must be specific
if ($dest_w <= 0 && $dest_h <= 0)
return false;
/**
* Filters whether to preempt calculating the image resize dimensions.
*
* Passing a non-null value to the filter will effectively short-circuit
* image_resize_dimensions(), returning that value instead.
*
* @since WP-3.4.0
*
* @param null|mixed $null Whether to preempt output of the resize dimensions.
* @param int $orig_w Original width in pixels.
* @param int $orig_h Original height in pixels.
* @param int $dest_w New width in pixels.
* @param int $dest_h New height in pixels.
* @param bool|array $crop Whether to crop image to specified width and height or resize.
* An array can specify positioning of the crop area. Default false.
*/
$output = apply_filters( 'image_resize_dimensions', null, $orig_w, $orig_h, $dest_w, $dest_h, $crop );
if ( null !== $output )
return $output;
if ( $crop ) {
// crop the largest possible portion of the original image that we can size to $dest_w x $dest_h
$aspect_ratio = $orig_w / $orig_h;
$new_w = min($dest_w, $orig_w);
$new_h = min($dest_h, $orig_h);
if ( ! $new_w ) {
$new_w = (int) round( $new_h * $aspect_ratio );
}
if ( ! $new_h ) {
$new_h = (int) round( $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);
if ( ! is_array( $crop ) || count( $crop ) !== 2 ) {
$crop = array( 'center', 'center' );
}
list( $x, $y ) = $crop;
if ( 'left' === $x ) {
$s_x = 0;
} elseif ( 'right' === $x ) {
$s_x = $orig_w - $crop_w;
} else {
$s_x = floor( ( $orig_w - $crop_w ) / 2 );
}
if ( 'top' === $y ) {
$s_y = 0;
} elseif ( 'bottom' === $y ) {
$s_y = $orig_h - $crop_h;
} else {
$s_y = floor( ( $orig_h - $crop_h ) / 2 );
}
} else {
// don't crop, just resize using $dest_w x $dest_h as a maximum bounding box
$crop_w = $orig_w;
$crop_h = $orig_h;
$s_x = 0;
$s_y = 0;
list( $new_w, $new_h ) = wp_constrain_dimensions( $orig_w, $orig_h, $dest_w, $dest_h );
}
// if the resulting image would be the same size or larger we don't want to resize it
if ( $new_w >= $orig_w && $new_h >= $orig_h && $dest_w != $orig_w && $dest_h != $orig_h ) {
return false;
}
// the return array matches the parameters to imagecopyresampled()
// int dst_x, int dst_y, int src_x, int src_y, int dst_w, int dst_h, int src_w, int src_h
return array( 0, 0, (int) $s_x, (int) $s_y, (int) $new_w, (int) $new_h, (int) $crop_w, (int) $crop_h );
}
Changelog
Version | Description |
---|---|
WP-2.5.0 | Introduced. |