Threshold of blurry image - part 2

Question

How can I threshold this blurry image to make the digits as clear as possible?

In a previous post, I tried adaptively thresholding a blurry image (left)

Answer 1

You probably want local thresholding. there are some general approaches for that.

Check the niblack algorithm. See also niblack thresholding. https://stackoverflow.com/a/9891678/461499 We successfully used this for document segmentation.