public static function addPreview($slug, $label, $width, $height)
    {
        static::_initPreviews();
        static::$_previews[$slug] = [
            'label' => $label,
            'width' => $width,
            'height' => $height,
        ];
    }
public static function addPreview($slug, $label, $width, $height)
    {
        static::_initPreviews();
        static::$_previews[$slug] = [
            'label' => $label,
            'width' => $width,
            'height' => $height,
        ];
    }
public static function addPreview ( $ slug , $ label , $ width , $ height ) { static :: _initPreviews ( ) ; static :: $ _previews [ $ slug ] = [ 'label' => $ label , 'width' => $ width , 'height' => $ height , ] ; }
Defines a new preview configuration or overwrite if exists.

@param string $slug Unique machine-name. e.g.: `my-preview-mode`
@param string $label Human-readable name. e.g.: `My preview mode`
@param int $width Width for images that would use this preview mode
@param int $height Height for images that would use this preview mode
@return void
Defines a new preview configuration or overwrite if exists .