In this paper, three new methods proposed for binarization of degraded documents and manuscripts. Phase congruency used to select regions of interest (ROI) of document's foreground. The main idea is to achieve an optimal recall measure (recall˜1), while the precision value is at an acceptable level. Further processing should be performed to focus on the ROI. We also used a modified adaptive thresholding method in the next step. This method uses a global variance, a global mean and local means for thresholding. Finally, a new method called early exclusion criterion (EEC) proposed for document enhancement. The experimental results on the datasets introduced in DIBCO 2009, H-DIBCO 2010 and DIBCO 2011 shows that near optimal recall value (recall˜0.99) obtained, while precision measure's value is acceptable.
['Hossein Ziaei Nafchi', 'Hamidreza Rashidy Kanan']
A phase congruency based document binarization