Translator Disclaimer
15 December 2003 Block adaptive binarization of business card images in PDA using modified quadratic filter
Author Affiliations +
Proceedings Volume 5296, Document Recognition and Retrieval XI; (2003)
Event: Electronic Imaging 2004, 2004, San Jose, California, United States
In this paper, we propose a block adaptive binarization (BAB) using a modified quadratic filter (MQF) to binarize business card images of ill conditions acquired by personal digital assistant (PDA) cameras. In the proposed method, a business card image is first partitioned into blocks of 8×8 and the blocks are then classified into character blocks (CBs) and background blocks (BBs) for locally adaptive processing. Each CB is windowed with 24×24 rectangular window centering around the CB and the windowed blocks are improved by the preprocessing filter MQF, in which the scheme of threshold selection in QF is modified. The 8×8 center block of the improved block is binarized with the threshold. A binary image is obtained tiling each binarized block in its original position. Experimental results show that the quality of binary images obtained by the proposed method is much better than that by the conventional global binarization (GB) using QF. In addition, the proposed method yields about 43% improvement of character recognition rate over the GB using QF.
© (2003) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Ki Taeg Shin, Ick Hoon Jang, Nam Chul Kim, Chong Heun Kim, and Tae Sik Kim "Block adaptive binarization of business card images in PDA using modified quadratic filter", Proc. SPIE 5296, Document Recognition and Retrieval XI, (15 December 2003);

Back to Top