›› 2019, Vol. 31 ›› Issue (6): 996-1004.DOI: 10.3969/j.issn.1004-1524.2019.06.18

• Biosystems Engineering • Previous Articles     Next Articles

Rice leaf geometric parameter measurement system based on B-spline curve

LU Yan1, 2, YANG Hongyun2, 3, *, ZHOU Qiong1, 2, SUN Yuting1, 2, YIN Hua2, 3   

  1. 1. School of Computer and Information Engineering, Jiangxi Agricultural University, Nanchang 330045, China;
    2. Key Laboratory of Agricultural Information Technology of Colleges and Universities in Jiangxi Province, Nanchang 330045, China;
    3. School of Software, Jiangxi Agricultural University, Nanchang 330045, China
  • Received:2018-12-03 Online:2019-06-25 Published:2019-06-26

Abstract: In order to obtain accurate geometric parameters of rice leaves non-destructively and to provide accurate data for agronomic research, the rice leaf geometric parameter measurement system based on B-spline curve was developed. The basic principle of B-spline curve fitting was elaborated, and the maximum leaf width of rice was obtained by using first order B-spline curve and the leaf length was obtained with gesture trajectory curve drawn to approximate the leaf vein based on cubic B-spline curve. Moreover, the number and position of control points could be manually intervened, therefore to realize real-time adjustment of the trajectory curve. In the results analysis, coefficient of variation (CV) and root mean square error (RMSE) were applied to evaluate the precision and accuracy of results. The leaf length CV was 2.4%, the leaf width CV was 5.4%, both were less than 15%, which meant that the results were of high precision; Meanwhile, linear regression fitting model of system prediction and measured values was established, found that the RMSE of leaf length was 1.534 0 cm and the RMSE of leaf width was 0.101 9 cm, which demonstrated that the system had excellent prediction ability. The results showed that the B-spline curve based measurement system could truly realize accurate acquisition of rice leaf length and leaf width conveniently and non-destructively and without much restriction in photo shooting, which provided a new measurement method for the determination of rice leaf geometric parameters and could satisfy the basic needs of agricultural scientific research.

Key words: rice leaf, leaf length, leaf width, B-spline curves, trajectory curve

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