非规则圆柱面壁画的高分辨率全景图像生成法

High resolution panorama generation method for irregular cylindrical murals

如何将洞窟甬道顶部的非规则柱面壁画展开成全景图像,在古壁画保护和二次开发领域是一个比较有挑战性的课题.提出了将柱面壁画先划分成众多有重叠的小区域进行采样,然后再把这些采样图像拼接成一幅全景图像的方法.该方法的主要处理内容:(1)依据采样图像集重构三维模型;(2)把图像纹理映射到三维模型上;(3)将重构得到的非规则三维圆柱面拟合到最接近于原形状的理想圆柱面上;(4)最后将理想圆柱面的壁画投影成全景图像.所提出的方法在实际洞窟图像集上进行了验证实验.实验结果显示,所提方法能较完整地生成全景图像,并且从全景图像上看不出有拼接痕迹和纹理变形的现象,具有一定的实用价值.

The issue of how to unfold an irregular cylindrical mural from the top surface of a cave corridor into a panorama is a challenge for researchers involved with ancient mural protection and secondary development.This paper presents a method of dividing cylindrical murals into many overlapping small areas for sampling firstly,and then stitching these sampled images into a panorama.The constituents of this method include the following key elements:(1)Reconstructing the 3D model with the sampled image set;(2)Mapping the image texture to the 3D model;(3)Fitting the reconstructed irregular 3D cylindrical surface to the ideal cylindrical surface which is closest to the original form;and(4)Projecting the mural of the ideal cylindrical surface to a panorama.The method proposed in this paper was verified on an actual cave image set.The experimental results showed that the proposed method can generate the panorama in full;moreover,there was no evidence of stitching traces or texture deformation on the panorama.The proposed method offers practical value for mural protection.