A simple tool for enhancement the photos of documents, notes, books, etc.

It makes lighting uniform and increases the contrast of the images.

python3 enhance.py img.jpg -o output.jpg --gray --sigma 50 --thrs 0.7 0.95

--gray makes grayscale image,

--sigma SIGMA is the parameter for Gaussian filter (required for uniform lighting),

--thrs LOW HIGH are two thresholds for contrast stretching,

--format FMT is the format of output image.