OCR Post-Processing Error Correction Algorithm using Google Online Spelling Suggestion

TL;DR

This paper presents a post-processing error correction algorithm for OCR outputs that leverages Google's online spelling suggestions to significantly improve correction accuracy of misspelled words.

Contribution

It introduces a context-based correction method using Google's database, enhancing OCR error correction beyond traditional approaches.

Findings

Significant improvement in OCR error correction rate

Effective detection and correction of non-word and real-word errors

Potential for parallelization and faster processing

Abstract

With the advent of digital optical scanners, a lot of paper-based books, textbooks, magazines, articles, and documents are being transformed into an electronic version that can be manipulated by a computer. For this purpose, OCR, short for Optical Character Recognition was developed to translate scanned graphical text into editable computer text. Unfortunately, OCR is still imperfect as it occasionally mis-recognizes letters and falsely identifies scanned text, leading to misspellings and linguistics errors in the OCR output text. This paper proposes a post-processing context-based error correction algorithm for detecting and correcting OCR non-word and real-word errors. The proposed algorithm is based on Google's online spelling suggestion which harnesses an internal database containing a huge collection of terms and word sequences gathered from all over the web, convenient to suggest possible replacements for words that have been misspelled during the OCR process. Experiments carried out revealed a significant improvement in OCR error correction rate. Future research can improve upon the proposed algorithm so much so that it can be parallelized and executed over multiprocessing platforms.