ALT A screenshot of a paper on arxiv, it reads: The possibility of making $138,000 from shredded banknote pieces using computer vision Every country must dispose of old banknotes. At the Hong Kong Monetary Authority visitor center, visitors can buy a paperweight souvenir full of shredded banknotes. Even though the shredded banknotes are small, by using computer vision, it is possible to reconstruct the whole banknote like a jigsaw puzzle. Each paperweight souvenir costs $100 HKD, and it is claimed to contain shredded banknotes equivalent to 138 complete $1000 HKD banknotes. In theory, $138,000 HKD can be recovered by using computer vision. This paper discusses the technique of collecting shredded banknote pieces and applying a computer vision program.

ALT A screenshot from the paper, it reads "The shredded banknotes were then collected. Surprisingly, three paperweight cylinders were opened, and two of them had stones in them". Three pictures follow.

ALT Screenshot from the paper, it reads: "This cylinder only contained 82.57/138 = 60% of the shredded banknote pieces that the label had claimed. Although this issue is not the focus of this paper, it appears that the Hong Kong Monetary Authority has broken the law."

ALT Screenshot from the paper, it reads: "The idea for this paper was discussed with the staff during my visit to the Hong Kong Monetary Authority visitor center. The paperweight souvenir is currently no longer available."