一种基于先验信息和多模板匹配的票据水印检测算法

An Algorithm for Detecting Bills′ Watermarks Based on Prior Information and Multi-template Matching

针对票据水印多目标检测过程中误检率和漏检率高的难题,提出了一种基于先验信息和多模板匹配的票据水印检测算法.该算法采用分级匹配的思想,首先选取初始水印模板进行单模板、粗匹配运算;然后利用票据水印的先验信息计算水印散布区间;接着在水印散布区间内进行多模板、细匹配运算;最后利用先验信息校验已检测到的水印位置,并估算未检测到的水印位置,降低水印检测的漏检率和误检率.仿真实验证明本算法误检率和漏检率低,可以有效地检测票据水印.

In order to reduce false-positive error probability and false-negative error probability for bills′ watermarks detection, an algorithm based on prior information and multi-template matching is proposed. By means of stepped-matching idea, it selects initial watermark template and uses single-template matching algorithm to find the approximate position of initial watermark template firstly. Secondly, it uses prior information to calculate watermarks′ scattering region. Thirdly, it uses multi-template matching algorithm to detect watermarks in the scattering region. Finally, it uses prior information to check the watermarks′ position that been detected, and to estimate the watermarks′ position that not been detected. The experiments show that the new algorithm can reduce the false-positive error probability and false-negative error probability, and it is effective to detect bills′ watermarks.