Adaptive binarization of severely degraded and non-uniformly illuminated documents

作者：Singh Brij Mohan^*; Sharma Rahul; Ghosh Debashis; Mittal Ankush

来源：International Journal on Document Analysis and Recognition, 2014, 17(4): 393-412.

DOI：10.1007/s10032-014-0219-6

• OCR
• Binarization
• Degraded documents
• Evaluation measures

This paper presents a new adaptive binarization method for the degraded document images. Variable background, non-uniform illumination, and blur caused by humidity are the addressed degradations. The proposed method has four steps: contrast analysis, which calculates the local contrast threshold; contrast stretching, thresholding by computing global threshold; and noise removal to improve the quality of binarized image. Evaluation of proposed method has been done using optical character recognition, visual criteria, and established measures: execution time, F-measure, peak signal-to-noise ratio, negative rate metric, and information to noise difference. Our method is tested on the four types of datasets including Document Image Binarization Contest (DIBCO) series datasets (DIBCO 2009, H-DIBCO 2010, and DIBCO 2011), which include a variety of degraded document images. On the basis of evaluation measures, the results of proposed method are promising and achieved good performance after extensive testing with eight techniques referred in the literature.

• 出版日期2014-12