基于改进SIFT算法的城市航拍图像快速拼接方法

Rapid Urban Aerial Image Stitching Method Based on Improved SIFT Algorithm

城市航拍图像在城市规划、土地管理、环境监测和基础设施建设等领域具有广泛应用。针对无人机航拍高度越高,图像捕获成本越高,图像质量或能见度越低的问题,使用低空无人机来大量捕获图像;针对经典的尺度不变特征转换(SIFT)图像拼接算法存在匹配稳定性差、拼接质量差的问题,提出一种改进SIFT算法,通过提取图像金字塔模型,提高了匹配的稳定性;采用RANSAC算法减少局外点的干扰,提高图像拼接质量;采用混合平均加权法消除重叠区域接缝,最终实现了图像快速精准拼接。仿真实验结果显示,改进后的SIFT算法在图像拼接稳定性和质量上均表现较好,能获得良好且完整的拼接图像。

Urban aerial images have extensive applications in urban planning,land management,environ-mental monitoring,and infrastructure development.Addressing the issue that higher drone flight altitudes lead to increased image capture costs and lower image quality or visibility,this study utilizes low-altitude UAVs for extensive image acquisition.SIFT algorithm is proposed to tackle the poor matching stability and alignment quality issues of the classical SIFT image stitching algorithm.By extracting an image pyramid model,the stability of matching is enhanced.The RANSAC algorithm is employed to reduce outliers and improve image alignment quality.Additionally,a hybrid averaging weighted method is used to eliminate seam artifacts in overlapping areas,ultimately achieving rapid and precise image stitching.Simulation results demonstrate that the improved SIFT algorithm performs well in both stitching stability and quality,producing satisfactory and complete stitched images.