Fundamental Matrix computation incorrect?

[an-kumar]

The computation of the fundamental matrix from two key frames (signature: cv::Mat LocalMapping::ComputeF12(KeyFrame *&pKF1, KeyFrame *&pKF2)) seems to be incorrect, when comparing to e.g Hartley and Zisserman's Multiple View Geometry. The equation is altogether different; in particular, in ORB_SLAM's computation, the skew symmetric matrix is computed from a vector which is entirely a function of the rotations and translations, whereas in Hartley and Zisserman's method, the skew symmetric matrix is computed from a vector which is also a function of the calibration matrix K.

(For reference, Hartley and Zisserman's method: Cameras not at infinity P = K [I | 0], P' = K' [R | t], F = K'^(-T) R K^(T) [KR^(T)t]×, where × indicates skew symmetric matrix).

Am I missing something?