A 2.5D surface structure reconstruction method using an imaging system with linear sensor

Abstract

In digital archiving of cultural heritages that have uneven and textured surfaces, it is challenging for researchers to acquire as much information as possible without having to used multiple techniques or devices. In this paper, a line-sensor camera based photometric stereo method for high-resolution 2.5D surface shape reconstruction is proposed. Compared to using an area sensor-based camera, a line sensor-based one can acquire higher resolution images with less geometric distortion, which can yield more accurate depth map results. A technique for estimating the lighting direction based on such system is addressed in detail for high-resolution surface shape reconstruction with improved efficiency. Experimental results yielded reconstructed depth maps comparable with the accuracy of conventional method like a laser ranger. In addition to surface reconstruction, the images acquired are colorimetrically accurate. This means that the method can produce both stereoscopic and spectroscopic information for digitizing cultural heritage with textured surfaces.