protected function buildImageSubdef(SimpleXMLElement $sd)
    {
        $image = new Image($this->translator);
        if ($sd->icodec) {
            $image->setOptionValue(Image::OPTION_ICODEC, (string) $sd->icodec);
        }
        if ($sd->size) {
            $image->setOptionValue(Image::OPTION_SIZE, (int) $sd->size);
        }
        if ($sd->quality) {
            $image->setOptionValue(Image::OPTION_QUALITY, (int) $sd->quality);
        }
        if ($sd->strip) {
            $image->setOptionValue(Image::OPTION_STRIP, p4field::isyes($sd->strip));
        }
        if ($sd->dpi) {
            $image->setOptionValue(Image::OPTION_RESOLUTION, (int) $sd->dpi);
        }
        if ($sd->flatten) {
            $image->setOptionValue(Image::OPTION_FLATTEN, p4field::isyes($sd->flatten));
        }
        return $image;
    }