Combination of local and dark stretching for Ziehl-Neelsen TB bacilli slide images in tissue and sputum samples

Abstract

Tuberculosis is an infectious and dangerous disease which can spread through the air when the infected person coughed, sneezed or spited. Sputum and tissue sample analysis is a common method for extra-pulmonary and pulmonary TB bacilli detection. Slide of sample stained with Ziehl-Neelsen stain is examined under light microscope with 40x digital magnification without oil immersion. Some factors can degrade the image quality such as noise, light exposure and staining problems. Thus, image enhancement is applied to produce better image in term of contrast and intensity. This paper will combined two steps of contrast enhancement technique which are local stretching and global stretching for tissue and sputum slide images. This technique has been tested onto 50 different images for each sample. The results obtained indicate that these methods may have some potential to improve the quality of slide images.