Pimcore\Image\Adapter\GD::sepia PHP Method

    public function sepia()
    {
        $this->preModify();
        imagefilter($this->resource, IMG_FILTER_GRAYSCALE);
        imagefilter($this->resource, IMG_FILTER_COLORIZE, 100, 50, 0);
        $this->postModify();
        return $this;
    }