目的 针对目前PQP点阵数据的识读算法准确率较低速度较慢的问题，为了加快该信息隐藏与印刷防伪方法的推广应用，文中设计一种基于PWM占空比判据的PQP快速识读算法。方法 首先对采集到的PQP图像在非校正条件下，利用脉冲宽度调制(PWM)和最小占空比寻优方法，估算其点阵图像的栅格角度，然后根据所求得的栅格角度参照PQP点阵图像，分别计算横纵2个方向的极大值序列，之后对该序列进行二次差分和自适应阈值判决以绘制PQP点阵数据识读栅格，最后以方形螺旋线指向顺序索引网格内各位置特征值来识读PQP点阵数据信息。结果 通过仿真和实验测试得出，当打印分辨率为600 dpi时，PQP图像信息的识读时间和误码率分别控制在0.5 s和±5%以内。结论 在非校正、无参考和盲同步信息等不确定条件下，实现了对PQP点阵图像的信息提取。

The work aims to design a PQP fast reading algorithm based on PWM duty cycle criterion, speed up the popularization and application of this information hiding and printing anti-counterfeiting method and solve the low accuracy and slow speed of PQP lattice data reading algorithm. First, the pulse width modulation (PWM) and the minimum duty cycle optimization method were adopted to estimate the grid angle of the acquired PQP image under non-correction conditions. Then, the maximum value sequence in the horizontal and vertical directions were calculated respectively based on the obtained grid angle with reference to the PQP dot matrix image. Next, the second difference and adaptive threshold judgment on the sequence were performed to draw the PQP dot matrix data reading grid. Finally, characteristic value of each position in the sequential index network pointed by the square spiral line was used to read the PQP dot matrix data information. Through simulation and experimental tests, when the printing resolution was 600 dpi, the reading time and bit error rate of PQP image information were controlled within 0.5 s and ±5%, respectively. The information extraction of PQP dot matrix image is realized under the uncertain conditions of uncorrected, unreferenced and blind synchronization information.