'get width and height of the video'

def dxy(self, file):

    file.seek((self.sequence_header_offset + 4), 0)
    v = file.read(4)
    x = (struct.unpack(u'>H', v[:2])[0] >> 4)
    y = (struct.unpack(u'>H', v[1:3])[0] & 4095)
    return (x, y)
