The quality of pineapple is one of the most concern things in an industry. Currently, the method of using the digital refractometer to measure the quality of pineapples is time-consuming and destructive. Another method of measuring the quality of pineapples is the hyperspectral imaging (HSI) method, which uses near infrared wavelength that is non-destructive to the fruit. However, HSI is expensive; consuming long data acquisition time and high dimensional data. This project aims to design and develop a non-invasive near infrared system with a multispectral imaging method by using a webcam and near infrared LEDs with the wavelengths between 850 and 950nm on an intact pineapple. After calibrating the webcam, the image taken for pineapple was clear and bright. By extracting the pixel values of the image taken, we were able to know the light intensity value of red (R), green (G), and blue (B) at that particular point in the image, allowing for comparison to be made between them. After conducting experiments with three same species of pineapples over a period of four days, the results obtained from the system designed indicated a high potential in determining the internal quality of pineapple. As the internal quality of the pineapples will remain almost the same, the light intensity value of certain points inside the image taken will also remain similar throughout the four days even the skin color of pineapples changed. Due to the consistent results of the experiment, it can be concluded that the proposed system is promising to be applied to predict the internal quality of pineapples non-invasively.
Keywords— pineapple, hyperspectral imaging method (HSI), multispectral imaging method