Simultaneous fruit detection and size estimation using multitask deep neural networks

The measurement of fruit size is of great interest to estimate the yield and predict the harvest resources in advance. This work proposes a novel technique for in-field apple detection and measurement based on Deep Neural Networks. The proposed framework was trained with RGB-D data and consists of a...

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Detalles Bibliográficos
Autores: Ferrer Ferrer, Mar, Ruiz Hidalgo, Javier|||0000-0001-6774-685X, Gregorio López, Eduard, Vilaplana Besler, Verónica|||0000-0001-6924-9961, Morros Rubió, Josep Ramon|||0000-0002-1395-487X, Gené-Mola, Jordi
Tipo de recurso: artículo
Fecha de publicación:2023
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/394650
Acceso en línea:https://hdl.handle.net/2117/394650
https://dx.doi.org/10.1016/j.biosystemseng.2023.07.010
Access Level:acceso abierto
Palabra clave:Deep learning
Precision farming
Fruit measurement
Yield estimation
Fruit visibility
Precision agriculture
Aprenentatge profund
Agricultura de precisió
Àrees temàtiques de la UPC::Enginyeria de la telecomunicació::Processament del senyal
Àrees temàtiques de la UPC::Enginyeria agroalimentària
Descripción
Sumario:The measurement of fruit size is of great interest to estimate the yield and predict the harvest resources in advance. This work proposes a novel technique for in-field apple detection and measurement based on Deep Neural Networks. The proposed framework was trained with RGB-D data and consists of an end-to-end multitask Deep Neural Network architecture specifically designed to perform the following tasks: 1) detection and segmentation of each fruit from its surroundings; 2) estimation of the diameter of each detected fruit. The methodology was tested with a total of 15,335 annotated apples at different growth stages, with diameters varying from 27 mm to 95 mm. Fruit detection results reported an F1-score for apple detection of 0.88 and a mean absolute error of diameter estimation of 5.64 mm. These are state-of-the-art results with the additional advantages of: a) using an end-to-end multitask trainable network; b) an efficient and fast inference speed; and c) being based on RGB-D data which can be acquired with affordable depth cameras. On the contrary, the main disadvantage is the need of annotating a large amount of data with fruit masks and diameter ground truth to train the model. Finally, a fruit visibility analysis showed an improvement in the prediction when limiting the measurement to apples above 65% of visibility (mean absolute error of 5.09 mm). This suggests that future works should develop a method for automatically identifying the most visible apples and discard the prediction of highly occluded fruits.