# tfg.rendering.camera.perspective.intrinsics_from_matrix

Extracts intrinsic parameters from a calibration matrix.

Extracts the focal length $$(f_x, f_y)$$ and the principal point $$(c_x, c_y)$$ from a camera calibration matrix

$$\mathbf{C} = \begin{bmatrix} f_x & 0 & c_x \\ 0 & f_y & c_y \\ 0 & 0 & 1 \\ \end{bmatrix}.$$

#### Note:

In the following, A1 to An are optional batch dimensions.

matrix A tensor of shape [A1, ..., An, 3, 3], where the last two dimensions represent a camera calibration matrix.
name A name for this op that defaults to "perspective_intrinsics_from_matrix".

Tuple of two tensors, each one of shape [A1, ..., An, 2]. The first tensor represents the focal length, and the second one the principle point.

ValueError If the shape of matrix is not supported.