Sub-pixel Corner Localization Function

Sub-pixel corner localization function code, which takes coarse pixel-level corner coordinates as input parameters and outputs precise sub-pixel level corner coordinates. Sub-pixel corner localization is a technique used to enhance the accuracy of corner coordinate positioning. Through further computational refinement and optimization of the initial pixel-level corner coordinates, more accurate sub-pixel level corner coordinates can be obtained. This technique is widely applied in computer vision and image processing fields, particularly in feature point detection and image matching tasks. The implementation typically uses interpolation methods (such as quadratic polynomial fitting or Gaussian interpolation) and gradient-based optimization algorithms to achieve sub-pixel precision. By utilizing the sub-pixel corner localization function code, the precision and accuracy of corner localization can be effectively improved, with common implementations including cornerSubPix() in OpenCV which employs iterative position refinement based on local gradient information.