Image fusion for autofocusing in fluorescence microscopy for tuberculosis screening

Automatic microscopy for screening of sputum smears for tuberculosis would reduce the reliance on technicians in heavily burdened laboratories in poorly-resourced countries. Autofocusing is a key component of automated microscopy. We investigate the use of wavelet-based image fusion for automatic focusing of sputum smear slides as a component of automated fluorescence microscopy to identify Mycobacterium tuberculosis. We use manual focusing as ground truth for assessing the performance of the algorithm. Image fusion produces images with a degree of focus comparable to that of a human operator.