A Fast Sub-pixel Image Registration Algorithm
Xuesong Zhang · Infrared Technology · 2013
The image super-resolution(SR) reconstruction is an effective method to enhance spatial resolution on the basis of existing infrared detectors.Image SR reconstruction is a process that obtains a high resolution image from a set of sub-pixel shifted low-resolution(LR) images.A rapid and high accuracy algorithm for estimating the shift between the images is one of the key technologies.In this paper,a fast sub-pixel registration algorithm is putted forward.The algorithm consists of three processes: feature detection,pixel-level registration and sub-pixel level registration.In the feature detection process,Firstly,we extract edges from the original images by Sobel operator.Secondly,preliminary detection of corner is used to remove the non-corner pixels.And finally,the Harris corners are extracted.In this way,the time for corner detecting is reduced greatly.In the pixel level registration process,we use NCC algorithm for registration,then statistical method is applied to remove false matching points.In the sub-pixel level registration process,we carry out interpolation in the neighborhood of the pixel-level match points,then the NCC matching and statistical method are used once again.Simulation experiment of the proposed algorithm is carried out,and the result shows that the speed of the proposed algorithm is significantly faster than the similar algorithms.