def _init_Q_matrix(self) -> Tensor:
        r"""Initialize the Q matrix of the horizontal stereo setup. See the Q property.

        Returns:
            The Q matrix of shape :math:`(B, 4, 4)`.

        """
        Q = zeros((self.batch_size, 4, 4), device=self.device, dtype=self.dtype)
        baseline: Tensor = -self.tx
        Q[:, 0, 0] = self.fy * baseline
        Q[:, 0, 3] = -self.fy * self.cx_left * baseline
        Q[:, 1, 1] = self.fx * baseline
        Q[:, 1, 3] = -self.fx * self.cy * baseline
        Q[:, 2, 3] = self.fx * self.fy * baseline
        Q[:, 3, 2] = -self.fy
        Q[:, 3, 3] = self.fy * (self.cx_left - self.cx_right)  # NOTE: This is usually zero.
        return Q
Initialize the Q matrix of the horizontal stereo setup. See the Q property.

        Returns:
            The Q matrix of shape :math:`(B, 4, 4)`.

        
kornia/geometry/camera/stereo.py