tfg.rendering.camera.perspective.ray

Computes the 3d ray for a 2d point (the z component of the ray is 1).

tfg.rendering.camera.perspective.ray(
    point_2d,
    focal,
    principal_point,
    name=None
)

Defined in rendering/camera/perspective.py.

Computes the 3d ray \((r_x, r_y, 1)\) from the camera center to a 2d point \((x', y')\) on the image plane with

$$ \begin{matrix} r_x = \frac{(x' - c_x)}{f_x}, & r_y = \frac{(y' - c_y)}{f_y}, & z = 1, \end{matrix} $$

where \((f_x, f_y)\) is the focal length and \((c_x, c_y)\) the principal point. The camera optical center is assumed to be at \((0, 0, 0)\).

Note:

In the following, A1 to An are optional batch dimensions that must be broadcast compatible.

Args:

  • point_2d: A tensor of shape [A1, ..., An, 2], where the last dimension represents a 2d point.
  • focal: A tensor of shape [A1, ..., An, 2], where the last dimension represents a camera focal length.
  • principal_point: A tensor of shape [A1, ..., An, 2], where the last dimension represents a camera principal point.
  • name: A name for this op that defaults to "perspective_ray".

Returns:

A tensor of shape [A1, ..., An, 3], where the last dimension represents a 3d ray.

Raises:

  • ValueError: If the shape of point_2d, focal, or principal_point is not supported.