Basically I a am using a function
bool niceHomography(const CvMat * H)
{
const double det = cvmGet(H, 0, 0) * cvmGet(H, 1, 1) - cvmGet(H, 1, 0) * cvmGet(H, 0, 1);
if (det < 0)
return false;
const double N1 = sqrt(cvmGet(H, 0, 0) * cvmGet(H, 0, 0) + cvmGet(H, 1, 0) * cvmGet(H, 1, 0));
if (N1 > 4 || N1 < 0.1)
return false;
const double N2 = sqrt(cvmGet(H, 0, 1) * cvmGet(H, 0, 1) + cvmGet(H, 1, 1) * cvmGet(H, 1, 1));
if (N2 > 4 || N2 < 0.1)
return false;
const double N3 = sqrt(cvmGet(H, 2, 0) * cvmGet(H, 2, 0) + cvmGet(H, 2, 1) * cvmGet(H, 2, 1));
if (N3 > 0.002)
return false;
return true;
}
to check whatever the homography is good or not (I have taken it from BRIEF_demo). Can anyone explain why we check the determinant like that?
Thanks