WALAILAK JOURNAL OF SCIENCE AND TECHNOLOGY

Volume 18, No. 10, Month MAY, Year 2021, Pages -

Weight estimation of asian sea bass (lates calcarifer) comparing whole body with and without fins using computer vision technique

Roongparit JONGJARAUNSUK, Wara TAPARHUDEE

Abstract Download PDF

An optimal model to evaluate the weight of the whole body of Asian sea bass with and without fins was generated using computer vision image processing techniques. Image data of 25 fish randomly selected were collected every week for one month. The data were divided into two sets by means of a 40 - 60 % split-test, 40 % (10 fish; 100 images) were used as training data and 60 % (15 fish; 150 images) were used as out-samples or validation data. The model using fish images without fins gave a higher average and total coefficient of determination (N150R2 = 0.77 ± 0.10, N600R2 = 0.96) than using images with fins (N150R2 = 0.24 ± 0.20, N600R2 0.63). Errors as root mean square error (RMSE), mean absolute error (MAE), mean absolute relative error (MARE), maximum absolute error (MXAE), and maximum relative error (MXRE) were compared using mathematical models. Results showed that the model using fish images without fins recorded fewer errors, with average values of 9.19 ± 3.74 g, 6.06 ± 3.64 g, 5.18 ± 3.08 %, 8.87 ± 3.26 g and 0.12 ± 0.12 %, respectively compared with fish images with fins at 12.35 ± 4.45 g, 11.26 ± 3.61 g, 9.69 ± 2.94 %, 11.50 ± 4.71 g and 0.14 ± 0.11 %, respectively. Comparison between models, with and without fins, and normal manual measurement methods found no statistically significant differences (P > 0.05). Therefore, this technique may be applied for weight estimation in real pond conditions to give advantages of reduced time, stress and injury, with minimal interference in fish feeding compared to physical capture and weighing.

Keywords

Computer vision technique, Fin, Weight estimation, Whole body, Asian sea bass, Image processing

---