# Inverse normalization in 8-point algorithm for fundamental matrix

The 8-point algorithm for Fundamental matrix, normalizes the pixel points before solving the linear system of equations and the solution is inverse normalized to get the Fundamental matrix.

Iam refering to the source at https://github.com/opencv/opencv/blob...

Lines 615 to 620

// apply the transformation that is inverse
// to what we used to normalize the point coordinates
Matx33d T1( scale1, 0, -scale1*m1c.x, 0, scale1, -scale1*m1c.y, 0, 0, 1 );
Matx33d T2( scale2, 0, -scale2*m2c.x, 0, scale2, -scale2*m2c.y, 0, 0, 1 );

F0 = T2.t()*F0*T1;


This appears to be same as the normalization procedure. Iam not able to understand how this is supposed to be inverse of the normalization. Any help is appreciated.

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