A Global-to-Local Approach to Binarization of Degraded Document Images

This article deals with binarization of degraded document images. In the proposed approach, Canny edge image of the input degraded document image is obtained after blurring it with a Gaussian filter. Next, the gray values of the two pixels of the input image at the left and right of each edge pixel...

Full description

Saved in:
Bibliographic Details
Main Authors: Biswas, Barun, Bhattacharya, Ujjwal, Chaudhuri, Bidyut B.
Format: Conference Proceeding
Language:English
Subjects:
adaptive thresholding
Binarization
Degradation
degraded document image
global thresholding
Histograms
Image color analysis
Image edge detection
PSNR
Smoothing methods
Online Access:Request full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:This article deals with binarization of degraded document images. In the proposed approach, Canny edge image of the input degraded document image is obtained after blurring it with a Gaussian filter. Next, the gray values of the two pixels of the input image at the left and right of each edge pixel are noted to form a histogram of these gray values which possesses two distinct peaks and the lowest valley between them provides the global threshold value. Each pixel with gray value greater than the above threshold is turned as background pixel. A small square window is considered around each non-background pixel and certain simple statistics are computed on the gray values of the pixels of this small window based on which the said pixel is turned either background or foreground. Such a local thresholding method at the latter stage can efficiently handle various degradations in the document. The binarized image so obtained is finally subjected to certain common post-processing operations. The proposed method has been compared with a few existing binarization techniques.
ISSN:1051-4651
2831-7475
DOI:10.1109/ICPR.2014.519