Forensic watermarking is often used to enable the tracing of digital pirates that leak copyright-protected videos. However, existing watermarking methods have a limited robustness and may be vulnerable to targeted attacks. Our previous work proposed a fallback detection method that uses secondary watermarks rather than the primary watermarks embedded by existing methods. However, the previously proposed fallback method is slow and requires access to all watermarked videos. This paper proposes to make the fallback watermark detection method faster using perceptual hashes instead of uncompressed secondary watermark signals. These perceptual hashes can be calculated prior to detection, such that the actual detection process is sped up with a factor of approximately 26,000 to 92,000. In this way, the proposed method tackles the main criticism about practical usability of the slow fallback method. The fast detection comes at the cost of a modest decrease in robustness, although the fast fallback detection method can still outperform the existing primary watermark method. In conclusion, the proposed method enables fast and more robust detection of watermarks that were embedded by existing watermarking methods.

中文翻译：

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使用感知哈希值的快速回退水印检测

法医水印通常用于跟踪泄漏受版权保护的视频的数字盗版者。但是，现有的加水印方法的鲁棒性有限，并且可能容易受到有针对性的攻击。我们之前的工作提出了一种后备检测方法，该方法使用次要水印而不是现有方法嵌入的主要水印。但是，先前提出的后备方法很慢，并且需要访问所有带水印的视频。本文提出使用感知哈希代替未压缩的辅助水印信号来使后备水印检测方法更快。这些感知哈希可以在检测之前进行计算，从而可以以大约26,000到92,000的因数加快实际检测过程。这样，提出的方法解决了关于慢速回退方法的实际可用性的主要批评。尽管快速回退检测方法仍能胜过现有的主要水印方法，但快速检测是以健壮性适当降低为代价的。总之，所提出的方法能够对现有水印方法所嵌入的水印进行快速，更鲁棒的检测。