图像拼接重建苹果树冠层器官三维形态  

Image mosaics reconstruction of canopy organ morphology of apple trees

作　　者：马晓丹[1,2] 孟庆宽[1] 张丽娇[1] 刘刚[1] 周薇[1] 

机构地区：[1]中国农业大学现代精细农业系统集成研究教育部重点实验室,北京100083 [2]黑龙江八一农垦大学信息技术学院,大庆163319

出　　处：《农业工程学报》2014年第12期154-162,共9页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金资助项目(31371532);国家自然科学基金子课题资助项目(31371532-C);中央高校基本科研业务费专项资金资助(2013YJ008)

摘　　要：为重建苹果树年生长期冠层器官三维形态,以休眠期、疏花期、成熟期苹果树冠层为研究对象,分别针对基于光合混合探测技术(photonic mixer detector,PMD)的摄像机与彩色摄像机获取的强度图像与彩色图像开展冠层图像拼接技术研究。利用Scale invariant feature transform算法的尺度不变特征,并结合Random sample consensus算法精确确定图像映射模型,避免了果园非结构光及图像尺度变换的影响。以此为基础,应用拉普拉斯金字塔分解与重构算法、分层确定融合规则,实现了不同生长期的冠层图像拼接,有效克服了传统融合算法反映细节信息能力差、拼接痕迹明显等缺点。果园不同环境下(晴天顺光、晴天逆光、阴天)的试验表明:提出的拼接方法适合于苹果树年生长期的冠层器官图像拼接,且算法的鲁棒性、速度及拼接精度均能满足冠层三维重建工作的要求,研究成果对提升剪枝、疏花、测产、采摘等果园管理的信息化水平具有重要意义。Annual growth cycle of fruit trees is the whole process of life activities with specific laws, including flower thing period and mature period. For a long time, how to construct the three-dimensional shape of an apple tree canopy with color information in different growth stages of fruit tree, has been always a research priority. At present, three methods are usually used to reconstruct 3D shape including stereo vision technology, laser scanner, and three-dimensional digitizer. The stereo vision technology is vulnerable to unstructured outdoor light. The use of a laser scanner can overcome the disadvantages above, but with slow speed to access information. The three-dimensional digitizer requires strict conditions of the external environment, and cannot obtain color information of objects. Photonic Mixer Device （PMD） is a three-dimensional imaging device based on time of flight technology, through which the distance information of objects could be obtained at a speed of 40fps. Although the resolution of the PMD is relatively low, it can be made up by color images. Therefore, the combination of the PMD camera and color camera might be a reliable tool to reconstruct the 3D shape of an apple tree canopy. Two or more inter-public areas of the images can be built into a larger view by image mosaics technology, which has been widely used in many fields, such as computer vision, medicine, and remote sensing, but has not been applied in the canopy organ image mosaics of apple trees in different growth stages. The image mosaics of the canopy are a key to the three-dimensional reconstruction of an apple tree. In order to reconstruct the three-dimensional shape of apple tree canopies in annual growth cycle, the apple tree canopies in the dormant period, the flower thinning period, and the mature period were set for the study, and the color and intensity images were captured by a color camera and a PMD camera based on photonic mixer detector technology, respectively. The images were investigated by mosaics technology fol

关 键 词：图像配准 图像融合 三维 苹果树 年生长期 冠层器官 多源图像 图像拼接 

分 类 号：TP242.62[自动化与计算机技术—检测技术与自动化装置] TP391.41[自动化与计算机技术—控制科学与工程]