Grayscale Image Acquisition for Raised Characters Based on Grating Image

Abstract

This paper presents a novel image acquisition technology for colorless raised characters. First, a grating image modulated with the height information of raised character is captured through a vision system; then, the Fourier transform method is used to get the phase of the grating image; finally, a rational design phase unwrapping method is designed to reconstruct the grayscale image of raised characters. Experiments show that the proposed method can get the well-separated images of raised characters.