I have used Tesseract for OCRing Japanese vertical texts and while it does work fine most of the time (not good mind you, since it constantly mixes certain comp

I have used Tesseract for OCRing Japanese vertical texts and while it does work fine most of the time (not good mind you, since it constantly mixes certain complex kanji, lack of advanced context awareness shows) after a bit of pre-processing (removing noise using threshold filtering, making characters darker, removing furigana), sometimes it simply breaks and produces a clear garbage. And page segmentation is not the only problem. I've wrote a custom algorithmic page segmentation (text from a page gets concatenated into a single "line") and Tesseract still breaks on certain inputs, removing several characters from the beginning of such text usually "fixes" this issue.