Fig 1.
The flow chart of image acquisition and processing.
Fig 2.
The original image and the images generated in each step of processing.
(a) Original Image; b) Gamma Transform; c) Median Filtering; d) HSV Transform; e) OTSU Segmentation; f) Morphological Treatment; g) Find Contours; h) Processing Result).
Fig 3.
Hue histograms of tomatoes with different maturities.
Table 1.
Grading results of tomato maturity classifier.
Fig 4.
The typical contour images of tomatoes.
Table 2.
The shape irregularities of different shaped tomatoes.
Table 3.
Grading results of tomato shape classifier.
Fig 5.
Linear regression model of tomato size.
Table 4.
Grading results of tomato size classifier.
Fig 6.
The flow of the comprehensive analysis.
Fig 7.
Automated tomato grading system.
(1. Conveying mechanism; 2. Visual inspection box; 3. Grading execution mechanism; 4. PLC controller; 5. Microcomputer).
Fig 8.
Structure of the visual inspection box.
(1. Photoelectric sensor; 2. Ring light source; 3. Camera).
Fig 9.
The operation interface of computer software.
Table 5.
The experimental results.