Segmentation of Plasmodium vivax phase on digital microscopic images of thin blood films using colour channel combination and Otsu method

Abstract

Malaria is a disease in human caused by Plasmodium parasite. Misdiagnosis and improperness in medical treatment towards this disease can lead to the death of patients. A number of digital image analysis-based research works to minimize the misdiagnosis has been developed. This research aims to segment the form of parasitic cells of Plasmodium using the combination of the red (R) channel in the RGB color space and saturation (S) channel in the HSV color space. The images used were parasitic cells of Plasmodium vivax, consisting of the phases of trophozoite, schizonts, and gametocytes. Each of which comprises ten samples. The process was begun by improving the image quality continued by separating the red channel in the RGB color space and by converting the image of RGB into the HSV image to obtain the saturation (S) channel. These two color channels were then combined in the form of a grayscale image. The further process was conducted by changing those grayscale image into the binary image using the Otsu method and the morphological operation to form it as the masking image. Of 30 tested images, the segmentation of the red (R) channel and saturation (S) channel combination achieved the accuracy of 93.33%, while the segmentation using saturation (S) channel produces result in the accuracy of 66.67%.