It's perfect from an OCR point of view: - Perfectly upright, no visible rotation - Sharp, not remotely blurry - No visible brightness/color gradient (as is often the case with pictures taken by mobile phones.)

It contains umlauts (and i'm not sure whether the tesseract training data for german includes those, but i'm quite certain it does), but that doesnt disqualify the image.

I was just saying hey, it's not using openCV but tesseract, so the title is wrong.. and i stand by that statement. I appreciate the work you do and i was exclusively referring to the title here. have a good day ;)