public/js/kcfinder/lib/class_image_gd.php
protected function output_png(array $options=array()) {
        $file = isset($options['file']) ? $options['file'] : null;
        $quality = isset($options['quality']) ? $options['quality'] : null;
        $filters = isset($options['filters']) ? $options['filters'] : null;
        if (($file === null) && !headers_sent())
            header("Content-Type: image/png");
        return imagepng($this->image, $file, $quality, $filters);
    }
protected function output_png(array $options=array()) {
        $file = isset($options['file']) ? $options['file'] : null;
        $quality = isset($options['quality']) ? $options['quality'] : null;
        $filters = isset($options['filters']) ? $options['filters'] : null;
        if (($file === null) && !headers_sent())
            header("Content-Type: image/png");
        return imagepng($this->image, $file, $quality, $filters);
    }
OWN METHODS