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Geometry with multiple views

I have two images taken from two cameras of the same marker, located at some distance from each other, capturing the same scene. I want to calculate the rotation and translation of the real world between two cameras. To achieve this, I first extracted the SIFT capabilities of both images and matched them.

Now I have a fundamental matrix , as well as a homography matrix . However, unable to continue further, a lot of confusion. Can someone help me evaluate the rotation and broadcast between the two cameras?

I use OpenCV to extract and map functions, homography calculations.

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If you have Homography, you also have a twist. When you have homography, it's easy to get a rotation and translation matrix.

For example, if you use OpenCV C ++:

param[in] H
param[out] pose
void cameraPoseFromHomography(const Mat& H, Mat& pose)
{
    pose = Mat::eye(3, 4, CV_32FC1);      // 3x4 matrix, the camera pose
    float norm1 = (float)norm(H.col(0));  
    float norm2 = (float)norm(H.col(1));  
    float tnorm = (norm1 + norm2) / 2.0f; // Normalization value

    Mat p1 = H.col(0);       // Pointer to first column of H
    Mat p2 = pose.col(0);    // Pointer to first column of pose (empty)

    cv::normalize(p1, p2);   // Normalize the rotation, and copies the column to pose

    p1 = H.col(1);           // Pointer to second column of H
    p2 = pose.col(1);        // Pointer to second column of pose (empty)

    cv::normalize(p1, p2);   // Normalize the rotation and copies the column to pose

    p1 = pose.col(0);
    p2 = pose.col(1);

    Mat p3 = p1.cross(p2);   // Computes the cross-product of p1 and p2
    Mat c2 = pose.col(2);    // Pointer to third column of pose
    p3.copyTo(c2);       // Third column is the crossproduct of columns one and two

    pose.col(3) = H.col(2) / tnorm;  //vector t [R|t] is the last column of pose
}

This function calculates the position of the camera from the homography that contains the rotation. For further theoretical information, follow this thread .

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