利用水下摄影测量技术测量鱼类体长的可行性研究

为研究用水下摄影测量系统测量鱼类体长的可行性,选取15尾大泷六线鱼Hexagrammos otakii作为研究对象,利用摄影测量系统测量鱼体体长并与人工实测数据进行对比。结果表明:摄影系统测量和人工测量两种测量方式测定出的数据相关系数为0.933(P=0.003);二者的相对误差范围为2.1%~18.1%,绝对误差范围为2.9~33.0 mm。研究表明,摄影测量鱼体长度与人工测量相比,测量结果存在一定误差,主要原因是鱼体控制点的提取较为困难,而人工测量本身也存在一定误差,因此,该摄影测量系统适用于水下测量鱼类体长。

Feasibility of measurement of fish body length using underwater photogrammetry

In present study,body length was measured in 15 individuals of fat greenling Hexagrammos otakii by an underwater photogrammetry system,in which a 3 d photogrammetric system was reconstructed via the calibration of distortion of the camera itself and the complex refraction of light in underwater environment,and compared with the body length measured manually to evaluate the feasibility of the fish length measurement using the underwater pho-togrammetry system. The results showed that the correlation coefficient of 0.933 was found between the values of body length measured by the underwater photogrammetry system and the body length measured manually,with sig-nificant difference of 0.003,relative error of 2.1%-18.1%,and absolute error of 2.9-33.0 mm. Manual measure-ment the measurement of fish body. There was error in body length measured by the underwater phogogrammetry system compared with the fish body length measured manually,which is primarily derived from the difficulty in fish control points extraction,and the certain error in manual measurement. The findings indicate that the underwater photogrammetry system can be used in measurement of fish body length even though it has some errors.