def getwin_buffer(self, order='RGB', alpha=1.0, dtype=None):
        """Same as :meth:`getwin_array`, but with the output array converted
        to C-order Python bytes.

        """
        outarr = self.getwin_array(order=order, alpha=alpha, dtype=dtype)

        if not hasattr(outarr, 'tobytes'):
            # older versions of numpy
            return outarr.tostring(order='C')
        return outarr.tobytes(order='C')