WP_Image_Editor_Imagick::pdf_setup PHP Method

    protected function pdf_setup()
    {
        try {
            // By default, PDFs are rendered in a very low resolution.
            // We want the thumbnail to be readable, so increase the rendering DPI.
            $this->image->setResolution(128, 128);
            // Only load the first page.
            return $this->file . '[0]';
        } catch (Exception $e) {
            return new WP_Error('pdf_setup_failed', $e->getMessage(), $this->file);
        }
    }