Pengembangan Metode Pengukuran Warna Menggunakan KamAera CCD (Charge Coupled Device) dan Image Processing

Abstract

One method that can be used in the measurement of color is with a CCD camera and image processing. The research objective was to develop an image processing algorithms for measuring color of horticultural products and compare the results of color measurement image processing methods with Chromameter. Object image was recorded in size of 744 × 480 pixels with 256 levels of light intensity of red, green and blue (RGB). The object image then was stored in a file with a bitmap format. The image processing Lab value was compared with Chromameter Lab value using a linear equation model. Coefficient of determination for Lab values for carrots on black color background were 0.827, 0.820, 0.826, respectively and on chayote were 0.905, 0.813, and 0.867 respectively. As for the white background, the coefficient of determination for carrots were 0.548, 0.786, 0.749, and for chayote were 0.793, 0.802, and 0.779. This occured because on the black color, all the spectrum of light was absorbed, therefore received energy of radiation in the black color became larger by increasing absorbed light specrum. In contrast, the white color reflected light spectrum. In addition there was interaction effect of light on the object being measured, such as reflection, absorption, distribution and shadow as a result of light blocking by the object. The quality of light and brightness levels that varied also affected the value of brightness.