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Local tools • Private document processing
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Local tools • Private document processing
Practical help:Recover missing text from a mixed PDF
How client-side text parsers, WebAssembly Tesseract OCR, and local recognition models extract textual data from digital and scanned PDFs.
CER = (Substitutions + Insertions + Deletions) / Total_Ground_Truth_CharactersIn academic character recognition evaluations, Character Error Rate measures the Levenshtein edit distance between the extracted sequence and the reference ground truth text.
No. When 'In-Browser Local Extraction' is selected, 100% of the extraction executes directly inside your browser using Mozilla PDF.js and Tesseract.js WebAssembly. Your files never touch an external server.
This release uses a printed-English OCR model. Handwriting and other languages may produce incorrect results. Use a clearer printed scan or a suitable dedicated OCR application, and verify the transcript against the source.
Digital text extraction simply reads pre-computed Unicode character strings. Scanned OCR must rasterize the image, compute gradient contours, and execute neural network inference across millions of individual pixels.
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