Precise Measurement of Two Dimensional Work-pieces on the Low-resolution Vision Condition

To solve the problem of precise edge localization and measurement on low-resolution images, statistics characters of edge gradient magnitude of both high and low resolution images along the gradient direction are extracted and analyzed. The gradient magnitude statistics is described with General Gaussian Distribution (GGD). The relationship between statistics of high and low resolution images is established via GGD analysis on training samples, based on which a high resolution gradient image is constructed from a low resolution image. Precise edge location and measurement are then achieved by double threshold edge detection and interpolation. Experiments show that the proposed method has better performance on precise measurement on two dimensional work-pieces than sub-pixel method only based on high precision interpolation.