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arXiv · 1912.07745

PDQ & TMK + PDQF -- A Test Drive of Facebook's Perceptual Hashing Algorithms

Janis Dalins·Campbell Wilson·Douglas Boudry
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Abstract

Efficient and reliable automated detection of modified image and multimedia files has long been a challenge for law enforcement, compounded by the harm caused by repeated exposure to psychologically harmful materials. In August 2019 Facebook open-sourced their PDQ and TMK + PDQF algorithms for image and video similarity measurement, respectively. In this report, we review the algorithms' performance on detecting commonly encountered transformations on real-world case data, sourced from contemporary investigations. We also provide a reference implementation to demonstrate the potential application and integration of such algorithms within existing law enforcement systems.

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Janis Dalins, Campbell Wilson, Douglas Boudry. 2019-12-16. PDQ & TMK + PDQF -- A Test Drive of Facebook's Perceptual Hashing Algorithms. https://arxiv.org/abs/1912.07745

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