Otsu Document Binarizer & Threshold Scanner
Convert shaded documents and paper scans into crisp black-and-white binary images for OCR.
Execution runs 100% locally inside the browser sandbox using HTML5 Canvas, Web Cryptography Subtle API, and Web Workers. No data is ever transmitted across the network.
Zero network latency. Operates completely offline with zero dependencies on third-party backend servers or cloud services.
Built according to official RFC specifications, cryptographic test vectors, and enterprise-grade data transformation standards.
How to Use Otsu Document Binarizer & Threshold Scanner
Upload a photo or phone scan of a document.
Let the Otsu variance optimizer calculate the optimal text cutoff.
Download clean monochrome PNG ready for printing or OCR.
Frequently Asked Questions
How does Otsu thresholding work?
Otsu's method analyzes the image histogram to find the threshold that minimizes intra-class variance between background paper and foreground ink.
Does this improve Tesseract OCR accuracy?
Yes, eliminating gradient shadows and grayscale noise significantly boosts OCR character recognition accuracy.
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