A Comment on "Analysis of Video Image Sequences Using Point and Line Correspondences"

TL;DR

This paper challenges previous claims by Wang et al. regarding motion analysis from video sequences, demonstrating that four points can suffice for motion recovery under orthogonal projection and simplifying the solution process.

Contribution

It refutes prior assertions by showing four points are enough for motion parameter recovery under orthogonal projection and introduces a linear solution approach.

Findings

Four traceable points suffice under orthogonal projection

Five points enable linear solution of two-frame motion problem

Disputes previous claims about line contributions and point sufficiency

Abstract

In this paper we would like to deny the results of Wang et al. raising two fundamental claims: * A line does not contribute anything to recognition of motion parameters from two images * Four traceable points are not sufficient to recover motion parameters from two perspective To be constructive, however, we show that four traceable points are sufficient to recover motion parameters from two frames under orthogonal projection and that five points are sufficient to simplify the solution of the two-frame problem under orthogonal projection to solving a linear equation system.