Colour Analysis of Strawberries on a Real Time Production Line

Abstract

A novel system has been designed where colour analysis algorithms facilitate grading ripeness of packed strawberries on a fast-paced production line. The Strawberry quality system acquires images at the rate of 2punnets/s, and feeds the images to the two algorithms. Using CIELAB and HSV colourspaces, both underripe and overripe colour features are analysed resulting in F1 scores of 94.7% and 90.6% respectively, when measured on multiple defect samples. The single defect class results scored 80.1% and 77.1%. The algorithms total time for the current hardware configuration is 121ms maximum and 80ms average, which is well below the required time window of 500ms. 105, 542 punnets have been assessed by the algorithm and has rejected 4, 952 in total (4.9%), helping to ensure the quality of the product being shipped to customers and avoiding costly returns.