Methods of Natural Image Preprocessing Supporting the Automatic Text Recognition Using the OCR Algorithms

2015 ◽  
pp. 143-150
Author(s):  
Piotr Lech ◽  
Krzysztof Okarma
Keyword(s):  
Text Recognition ◽  
Natural Image ◽  
Image Preprocessing ◽  
Automatic Text

scholarly journals Improvement of Image Binarization Methods Using Image Preprocessing with Local Entropy Filtering for Alphanumerical Character Recognition Purposes

Entropy ◽  
2019 ◽  
Vol 21 (6) ◽  
pp. 562 ◽  
Author(s):  
Hubert Michalak ◽  
Krzysztof Okarma
Keyword(s):  
Character Recognition ◽  
Optical Character Recognition ◽  
Text Recognition ◽  
Document Images ◽  
Image Binarization ◽  
Image Preprocessing ◽  
Lighting Conditions ◽  
Automatic Text ◽  
Local Image

Automatic text recognition from the natural images acquired in uncontrolled lighting conditions is a challenging task due to the presence of shadows hindering the shape analysis and classification of individual characters. Since the optical character recognition methods require prior image binarization, the application of classical global thresholding methods in such case makes it impossible to preserve the visibility of all characters. Nevertheless, the use of adaptive binarization does not always lead to satisfactory results for heavily unevenly illuminated document images. In this paper, the image preprocessing methodology with the use of local image entropy filtering is proposed, allowing for the improvement of various commonly used image thresholding methods, which can be useful also for text recognition purposes. The proposed approach was verified using a dataset of 140 differently illuminated document images subjected to further text recognition. Experimental results, expressed as Levenshtein distances and F-Measure values for obtained text strings, are promising and confirm the usefulness of the proposed approach.

scholarly journals Automatic text segmentation and text recognition for video indexing

2000 ◽  
Vol 8 (1) ◽  
pp. 69-81 ◽  
Author(s):  
Rainer Lienhart ◽  
Wolfgang Effelsberg
Keyword(s):  
Video Indexing ◽  
Text Recognition ◽  
Text Segmentation ◽  
Automatic Text

Automatic Text Recognition in Web Images

2017 ◽  
Author(s):  
Rodolfo Valiente ◽  
José C. Gutiérrez ◽  
Marcelo T. Sadaike ◽  
Graça Bressan
Keyword(s):  
Text Recognition ◽  
Web Images ◽  
Automatic Text

Assessing the impact of graphical quality on automatic text recognition in digital maps

2016 ◽  
Vol 93 ◽  
pp. 21-35 ◽  
Author(s):  
Yao-Yi Chiang ◽  
Stefan Leyk ◽  
Narges Honarvar Nazari ◽  
Sima Moghaddam ◽  
Tian Xiang Tan
Keyword(s):  
Text Recognition ◽  
Digital Maps ◽  
The Impact ◽  
Automatic Text
Sign in / Sign up

Export Citation Format

Share Document