OpenCV for OCR: How to compute thresholding levels for gray image OCR

Question

I\'m trying to prepare images for OCR, and so far here is what I\'ve done using info from Extracting text OpenCV

From the resulting image I use the contours that hav

Answer 1

You could try to erase all the text with an erosion and then subtract the result from the grayscale image or use a tophat transform instead to uniform your background for global thresholding! Here you can find an example code! And why not use the existing adaptiveThreshold function ?