Using Direct Linear Transformation to find Homography

Direct Linear Transform (DLT)

Using Direct Linear Transformation to find Homography.

With the 4 correspondences, we can solve Direct Linear Transform (DLT) for the homography matrix H.

However, a correspondence model may contain both inliers and outliers.

Random Sample Consensus (RANSAC)

In order to filter out the outliers, to reconstruct the model, use RANSAC in an iterative fashion.

For example, for every set of 4 correspondences randomly picked, the occurrence of H is calculated.

Using this H value, we can determine the outlier correspondences.

With only inliers, we can recalculate H for each set of 4 correspondences.

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