Method for sharpening combined stereo images in the presence of optical distortions

A method for combining images taken from different angles in the presence of lens distortions is the subject of the research. Purpose of the work. Away to reduce image blurring when transferring one image into another coordinate system is developed. Method. The problem of transferring an image from the coordinate system of the original two images through a single transformation is considered. An expression representing a superposition of several geometric transformations associated with distortions caused by the distortions of two lenses and the individual shift of all pixels, determined by stereovision or optical flowmethods, is obtained. Results. A feature of the problem is that some of the transformations are described analytically (distortions), and some are described by a matrix of pixel shifts. It is demonstrated that, for this problem, transformations are more effective when they are described using a mapping matrix instead of an optical flow. Expressions that connect the coordinate systems of two images directly are derived. The proposed approach of encapsulating the distortion equations into a matrix describing the optical flow of rectified images makes it possible to improve the quality of the image converted to the coordinate system of the second frame. This is achieved by avoiding the sequential transfer of the image into several intermediate coordinate systems, which are associated with the use of bilinear interpolation and, consequently, excessive smoothing. It is proven through experiment that the proposed approach yields images with better characteristics compared with the traditional approach. Practical significance. The developed method can be applied in optoelectronic systems with multiple lenses in various tasks, including those requiring improving the image of a wide-angle camera using the image of a narrow-field lens. (c) 2024 Optica Publishing Group