The use of CLAHE for improving an accuracy of CNN architecture for detecting pneumonia Elbert Alfredo Tjoa, I Putu Yowan Nugraha Suparta, Rita Magdalena and Nor Kumalasari CP SHS Web Conf., 139 (2022) 03026 Published online: 13 May 2022 DOI: 10.1051/shsconf/202213903026