Abstract: Theoretical analysis and simulation experiments have been done to solve how to get the target samples in detecting of randomly distributed target samples efficiently.Approximate parameter formula and curve have been given.Minimum number of random samples has been only determined by the proportion between randomly marked samples and total samples.This conclusion can be applied to many fields,such as video digital watermark.

Key words: random distribution, target samples, minimum number of random samples, samples detection, video watermark

摘要： 对实际研究和应用中经常出现的两次随机采样中的样本重复（即随机分布的目标样本检测）问题进行了理论分析和系统仿真,总结出两次随机采样中样本重复的近似条件关系式和关系曲线,且临界随机采样数量仅与随机被标记样本占总样本的比例有关。最后,将该结论应用到视频数字水印系统等实际问题中,证明该结论的有效性和实用性。

关键词: 随机分布, 目标样本, 临界随机采样数量, 样本检测, 视频水印