Noise Removal Technique for Document Images
Brij Mohan Singh, Kamal Kant Verma, Mridula · Journal of Multimedia Information System · 2023
The documents may contain noise at the time of scanning, transmission or during converting into it in digital form. The noise may be categorized after finding the features and may find the same patterns in the document image in order to obtain the accurate method for their elimination. The removal of noise from the document image is an important phase for the development of high-quality Optical Character Recognition (OCR) system. To make this possible, this paper presents a robust noise removal method for the noised natural document images. As per proposed algorithm, the connected black pixels are identified and determined the number of pixels they contained. Then from the collected data, density of the black pixels below which all the connected pixels represent noise is calculated. Those pixels having value less then calculated values are removed. The results of proposed approach were tested against Weiner, Median, and Average filters. The value of standard performance measures such as PSNR, F-measure and NRM are 22.77 dB, 82.36 and 1.09 for test image1, 22.46 dB, 96.63% and 1.409 for test image2, 22.79 dB, 96.22% and 0.7927 for test image3, 24.01 dB, 96.63% and 0.3739 for test image4, 24.64 dB, 97.7949, and .4833 for test image5. The obtained results of proposed approach are better as compare to average, Weiner and Median filters.