A Novel Approach to Pod Count Estimation Using a Depth Camera in Support of Soybean Breeding Applications

Improving soybean (<i>Glycine max</i> L. (Merr.)) yield is crucial for strengthening national food security. Predicting soybean yield is essential to maximize the potential of crop varieties. Non-destructive methods are needed to estimate yield before crop maturity. Various approaches, i...

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Bibliographic Details
Main Authors: Jithin Mathew, Nadia Delavarpour, Carrie Miranda, John Stenger, Zhao Zhang, Justice Aduteye, Paulo Flores
Format: Article
Language:English
Published: MDPI AG 2023-07-01
Series:Sensors
Subjects:
Online Access:https://www.mdpi.com/1424-8220/23/14/6506
Description
Summary:Improving soybean (<i>Glycine max</i> L. (Merr.)) yield is crucial for strengthening national food security. Predicting soybean yield is essential to maximize the potential of crop varieties. Non-destructive methods are needed to estimate yield before crop maturity. Various approaches, including the pod-count method, have been used to predict soybean yield, but they often face issues with the crop background color. To address this challenge, we explored the application of a depth camera to real-time filtering of RGB images, aiming to enhance the performance of the pod-counting classification model. Additionally, this study aimed to compare object detection models (YOLOV7 and YOLOv7-E6E) and select the most suitable deep learning (DL) model for counting soybean pods. After identifying the best architecture, we conducted a comparative analysis of the model’s performance by training the DL model with and without background removal from images. Results demonstrated that removing the background using a depth camera improved YOLOv7’s pod detection performance by 10.2% precision, 16.4% recall, 13.8% mAP@50, and 17.7% mAP@0.5:0.95 score compared to when the background was present. Using a depth camera and the YOLOv7 algorithm for pod detection and counting yielded a mAP@0.5 of 93.4% and mAP@0.5:0.95 of 83.9%. These results indicated a significant improvement in the DL model’s performance when the background was segmented, and a reasonably larger dataset was used to train YOLOv7.
ISSN:1424-8220