def __init__(self, a, r, g, b):
nx, ny = r.shape
argb = (a << 24) | (r << 16) | (g << 8) | b
# transpose array, as it is in column-major (C order), while QImages are in row-major order
dprint(5, "making qimage of size", nx, ny)
self._buffer = argb.transpose().tostring()
QImage.__init__(self, self._buffer, nx, ny, QImage.Format_ARGB32)
