public function setPostProcessingOptions($options)
    {
        if (isset($options['jpeg_optimize']) && $options['jpeg_optimize']) {
            $this->jpegOptimizeCmd = $options['jpeg_optimize_cmd'];
        } else {
            $this->jpegOptimizeCmd = null;
        }

        if (array_key_exists("png_lossy", $options) 
            && $options['png_lossy'] !== false) {
            $this->pngLossy = $options['png_lossy'];
            $this->pngLossyCmd = $options['png_lossy_cmd'];
        } else {
            $this->pngLossyCmd = null;
        }

        if (isset($options['png_filter']) && $options['png_filter']) {
            $this->pngFilterCmd = $options['png_filter_cmd'];
        } else {
            $this->pngFilterCmd = null;
        }

        if (isset($options['png_deflate']) && $options['png_deflate']) {
            $this->pngDeflateCmd = $options['png_deflate_cmd'];
        } else {
            $this->pngDeflateCmd = null;
        }

        return $this;
    }