The disclosure provides methods and systems for determining tissueoxygenation. Anelectronic device obtains a data set including a plurality of images of atissue of interest, eachresolved at a different spectral band. Spectral analysis is performed, uponimage registration, ata plurality of points in a two-dimensional area of the images of the tissue.The spectral analysisincluding determining approximate values of oxyhemoglobin levels anddeoxyhemoglobin levelsat each respective point in the plurality of points. The predetermined set ofeight to twelvespectral bands includes spectral bands that provide improved methods formeasuring tissueoxygenation.