摘要
文档图像存在墨迹浸润等复杂背景特性,针对该问题,提出结合背景估计与能量函数的低质量文档图像二值化算法。基于相对暗特征和笔画宽度变换方法,估计文档图像的笔画宽度,采用形态学闭操作估计图像背景,通过能量函数最小化完成文档图像二值化。实验结果表明,该算法能有效抑制文档图像背景,取得较优的二值化结果,在F值(Fmeasure,FM)、伪F值(pseudo F-measure,p-FM)和错误率度量(negative rate metric,NRM)等性能指标上均优于LMM等经典二值化算法。
Complex background features such as bleed through exist in document images,a degraded document image binarization algorithm based on background estimation and energy function was proposed.Combined relative darkness features with stroke width transform,the document background was estimated by morphological closing operations,and the document image binarization was completed by minimizing the energy function.Experimental results show that the proposed algorithm can effectively suppress the document background and obtain better binary results.The proposed method outperforms other state-of-the-art techniques in terms of F-measure,pseudo F-measure,and NRM.
引文
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