摘要
针对海上低纹理、大视差图像拼接过程中由于误对齐产生的伪影问题,提出一种基于点线特征配准和最佳接缝线融合的几何结构保视差图像拼接算法。在传统的基于点特征求解单应变换的基础上引入线段特征,并将潜在的共面局部线段合并为全局线段,为接缝线融合提供精准对齐的条件;在图像融合过程中,利用tanh度量的颜色差异和梯度差异以及引入显著性检测权重来设计接缝切割方法的能量函数,引导最佳接缝线避开图像中显著海上结构,从而确保结构边缘的连续性;使用SIFT flow方法校正拼接缝上的错位像素,实现几何结构准确的海上图像拼接。在20对不同场景数据上的拼接实验表明,与基准方法相比,所提算法的基于SSIM的接缝质量误差平均降低了44.6%,最多降低66.7%,基于ZNCC(zero mean normalized cross-correlation)的接缝质量误差平均降低了24.7%,最多降低了51.6%,能够有效地避免伪影,从而得到观感自然的拼接结果,满足无人船航行过程中对宽视场的需求。
In order to address the artifacts caused by misalignment in maritime image stitch with low texture and large parallax,a geometric structure parallax-tolerant image stitch algorithm based on point-line feature registration and optimal seam fusion is proposed.Line segment features are introduced into the traditional homography transformation based on point features,and potential coplanar local line segments are merged into global line segments to provide accurate alignment conditions for seam line fusion.In the image fusion stage,the energy function of seam cutting method is designed by using the color difference and gradient difference of tanh measure and introducing saliency detection weight,which guides the optimal seam to avoid prominent maritime structures in the image,thus ensuring the continuity of structural edges.The SIFT flow method is used to correct the misalignment pixels on the stitching seam,and the maritime image stitching with accurate geometric structure is realized.Experimental results,based on 20 pairs of diverse scene data,compaed with the baseline method,the proposed algorithm achieves an average 44.6%reduction in seam quality error based on structural similarity,with a maximum reduction of 66.7%.The average reduction in seam quality error based on zero mean normalized cross-correlation is 24.7%,with a maximum reduction of 51.6%.The algorithm can effectively avoid artifacts,thus achieving visually natural stitching results and satisfying the requirements for a wide field of view during unmanned ship navigation.
作者
杨志林
尹勇
张如凯
景乾峰
姜森
朱文锋
Yang Zhilin;Yin Yong;Zhang Rukai;Jing Qianfeng;Jiang Sen;Zhu Wenfeng(Key Lab.of Marine Simulation and Control,Dalian Maritime University,Dalian 116026,China;Department of navigation,Tianjin Maritime College,Tianjin,300350,China)
出处
《系统仿真学报》
CAS
CSCD
北大核心
2024年第8期1749-1763,共15页
Journal of System Simulation
基金
国家重点研发计划(2022YFB4301402)。
关键词
无人船视觉感知
图像拼接
点线一致性配准
几何结构保护
最佳接缝线融合
unmanned ship visual perception
image stitching
point-line consistence registration
geometric structure protection
optimal seam fusion
